Merc V6 History

[warrior74z]

Was anyone out there connected with Merc Marine when the V6 was being developed and can share some knowledge on the history of the original Black Max. Its been 31 years now since the production model first appeared.

[JFL]

I was and have some parts from then.

[AirRide]

To The Top for V-6 Merc History...

[mk30h]

When did the design work commence? What were the rejected competing designs at Merc/ Was there thoughts of a inline 6 looper, V4 looper etc. This should be interesting.
I know that Merc had worked on V designs before OMC back in the late 40's early 50's.

[rckid74]

Testing reply

[RBT]

This would be a neat thread if we ever could get it going.

[rckid74]

Yea, I've tried three times to post my comments and they get rejected every time. This will probably go thru.

[Dave S]

HaaHaa First merc looper... V4 drone....Fuel injeted... offset crank jornels..looper....shot down in the air at 265 mph....1962..... heehee....

[Dave S]

sorry 1952.....

[rckid74]

The V6 that the Chrysler/Force group built was a direct copy of the Merc V6 and occured somewhat later than 1971. --- That engine now resides at the auto museum at Hartford, WI. You'll also find probably the only existing Mercury personal water craft (Jet ski) there too. I did the engine design on that also.

[rckid74]

My name is Jerry Hale and I was project engineer for Mercury's (Black Max) 2 liter V6. Just to authenticate my position there, you can look up the following patents which are in my name (actually in the name of ("David Jerry Hale"), I go by my middle name. Patent #4,092,958 (Internal Combustion Engine), patent #4,066,057 (Cylinder Head Mounting Apparatus for Internal Combustion Engines), and patent #4,082,068 (V-Engine Cooling System particularly for Outboard Motors and the like), all assigned to Brunswick Corp and all pertaining to the V6.
There seems to be some interest in just how this engine came about so I thought that, before Alzheimer's sets in, I had better get down on paper just what happened back there 43 years ago. I intend to do this in small weekly installments or as nearly weekly as I can manage.
The project was started in Jan. of 1970 at Mercurys outboard engineering plant #6 in Oshkosh, WI. The inital study, as presented to me, was to determine the best configuration; inline, V, or opposed and how many cylinders. It was to be a looper with 2 liters displacement capable of being bored for another 10% increase, have a diecast block, and was to have the lightest weight and smallest package size possible. The max power was to be at least 10% above the 1350 (135HP) inline six then in production, i.e., 150HP. (more later)

[FUJIMO]

My name is Jerry Hale and I was project engineer for Mercury's (Black Max) 2 liter V6. Just to authenticate my position there, you can look up the following patents which are in my name (actually in the name of ("David Jerry Hale"), I go by my middle name. Patent #4,092,958 (Internal Combustion Engine), patent #4,066,057 (Cylinder Head Mounting Apparatus for Internal Combustion Engines), and patent #4,082,068 (V-Engine Cooling System particularly for Outboard Motors and the like), all assigned to Brunswick Corp and all pertaining to the V6.
There seems to be some interest in just how this engine came about so I thought that, before Alzheimer's sets in, I had better get down on paper just what happened back there 43 years ago. I intend to do this in small weekly installments or as nearly weekly as I can manage.
The project was started in Jan. of 1970 at Mercurys outboard engineering plant #6 in Oshkosh, WI. The inital study, as presented to me, was to determine the best configuration; inline, V, or opposed and how many cylinders. It was to be a looper with 2 liters displacement capable of being bored for another 10% increase, have a diecast block, and was to have the lightest weight and smallest package size possible. The max power was to be at least 10% above the 1350 (135HP) inline six then in production, i.e., 150HP. (more later)
This is Great! Welcome Jerry! Cannnot wait to hear your next contribution, regarding the 122/60 degree. Thank-You.

[FUJIMO]

Keith Gagnier, Ralph Anderson, Gene Triechel, etc., from the 2-cycle shop(engineering), V-225/3.4L program. Good guys.

[Rotary John]

Jerry: I find it interesting that going to a looper from cross and increasing the displacement by 22% the goal was only a 10% increase in power. Can you explain?

[rckid74]

Yes Fujimo, Keith and Ralph both came into the 951 (V6) project shortly after we got the first sand cast engines running. I don't recognize the Triechel name though. He's not on the plant 6 honor roll of names either. This listing of names includes everyone that ever worked at plant 6 over the years and includes such notables as Carl Kiekhaefer, Charles Alexander, Charlie Strang, and several others listed as "Guest Workers", such as Tony Bettenhausen, Briggs Cunningham, Tim Flock, Bill France, Ted Jones, Jack Leek, Maury Rose, Red Vogt, "Gorgeous George" Wagner, Lee Wallard, Phil Walters, and Gar Wood Jr. Pretty impressive names, Huh. These had all been and gone before I arrived in March of 1965. Several of these were of course associated with Mr. K's car racing back in the 50's and there were remnants of those days still extant in the garages out back such as the car lifts, hot honing machine and valve grinding equipment.
A couple of other names of guys that came into the V6 project about a year after it started are Ron Anderson and Joe Harrelson, both engineers who contributed much. You may be familiar with Ron because he's the guy that took the production "Black Max" and made it into the fire-breathing T3 race engine you have today. He later went on to have his own prop shop and marina out in Seattle. Joe went on to become a college professor at a school out in CA. teaching engine design. He also designed and built a large V4 engine used by a group to set a world motorcycle speed record a few years back.
While I'm at it, I'd like to recognize several other people who played major rolls in the V6 project, it certainly was not a one man show. Robert "Bob" Johnson (RTJ) manager of outboard engineering and manager of plant 6 is the guy who gave me the list of requirements for the engine, which I listed in my previous entry. So I can only suppose he's the one that originated the "Black Max" V6 idea. It may have come down from higher up the ladder but I doubt it. Kiekhaefer was pretty much out of the picture by then (1970) and I doubt was even aware there was a new engine in the offing. I often wondered how he felt about the V6 later when he did find out about it. Probably wasn't happy about it displacing his "baby" the inline 6. Other contributors were Dick Lanpheer, our sound and vibration engineer who took over management of the V6 project shortly after it got started; Al Tyner, my board man who did most of the detail design of the engine; Dave Kusche, who did the cowling design and worked closely with our stylist Art Miller, who did a fantastic job styling that original engine. I still think that was the best looking of all the "Black Max" cowls. Then there was Elmer Croisant, responsible for the undercarriage; Bob Schmeidel, electrical; and Jim Meininger, carburetion. And of course there were many others not directly involved in the design but every bit as essential for it's success such as my lead technician Paul Jennerjohn and all the techs, our shop foreman Vern Habeck and all the model shop machinists, Paul Crane and all the drafting personell. They all did their parts to make Black Max a success.
I'll get on with the design next time.

[rock]

Thank you sir and welcome to the site. This will be good.

Rock

[RBT]

Amazing, some of the most interesting, best reading I have ever had the privilege to enjoy here.
please keep,it up.

RT

[bernie]

Hi Jerry, looking forward to "the rest of the story". I see you started in March of '65 - I started in April of '65. Uncle Sam got me later in '65 and I didn't return until 1968, in QC over at Plant 4, then in '70 I took over as Chief Inspector at 4. I can still remember a fellow from Plant 6 that would come down with a metal toolbox with V6 cranks in it to get the flywheel splines added and then take them out to the Heat Treat building. Can't remember his name, drove a little car - his son worked dock endurance at 33. Bernie Bergen

[Greg G]

Wow, some cool info gonna be traded here for the archives!

[FUJIMO]

Yes Fujimo, Keith and Ralph were both in my group at the start of the 951 (V6) project. I don't recognize the Triechel name though. He's not on the plant 6 honor roll of names either. This listing of names includes everyone that ever worked at plant 6 over the years and includes such notables as Carl Kiekhaefer, Charles Alexander, Charlie Strang, and several others listed as "Guest Workers", such as Tony Bettenhausen, Briggs Cunningham, Tim Flock, Bill France, Ted Jones, Jack Leek, Maury Rose, Red Vogt, "Gorgeous George" Wagner, Lee Wallard, Phil Walters, and Gar Wood Jr. Pretty impressive names, Huh. These had all been and gone before I arrived in March of 1965. Several of these were of course associated with Mr. K's car racing back in the 50's and there were remnants of those days still extant in the garages out back such as the car lifts, hot honing machine and valve grinding equipment.
A couple of other names of guys that came into the V6 project shortly after it started are Ron Anderson and Joe Harrelson, both engineers who contributed much. You may be familiar with Ron because he's the guy that took the production "Black Max" and made it into the fire-breathing T4 race engine you have today. He later went on to have his own prop shop and marina out in Seattle. Joe went on to become a college professor at a school out in CA. teaching engine design. He also designed and built a large V4 engine used by a group to set a world motorcycle speed record a few years back.
While I'm at it, I'd like to recognize several other people who played major rolls in the V6 project, it certainly was not a one man show. Robert "Bob" Johnson (RTJ) manager of outboard engineering and manager of plant 6 is the guy who gave me the list of requirements for the engine, which I listed in my previous entry. So I can only suppose he's the one that originated the "Black Max" V6 idea. It may have come down from higher up the ladder but I doubt it. Kiekhaefer was pretty much out of the picture by then (1970) and I doubt was even aware there was a new engine in the offing. I often wondered how he felt about the V6 later when he did find out about it. Probably wasn't happy about it displacing his "baby" the inline 6. Other contributors were Dick Lanpheer, our sound and vibration engineer who took over management of the V6 project shortly after it got started; Al Tyner, my board man who did all the detail design of the engine; Dave Kusche, who did the cowling design and worked closely with our stylist Art Miller, who did a fantastic job styling that original engine. I still think that was the best looking of all the "Black Max" cowls. Then there was Elmer Croisant, responsible for the undercarriage; Bob Schmeidel, electrical; and Jim Meininger, carburetion.
I'll get on with the design next time.
Great to hear those names again Jerry. You certainly created, in my opinion, the best piece of engineering that the name "Mercury Outboards" ever produced. You should know Bernie Bergen, although the empire was so big back then, it would have been easy for him to travel down another fork in the road & not cross paths. Bernie retired as an applications engineer, for sterndrives & outboards at the oem level, (Hi-Perf included)etc., just a couple years back. Thanks for all your retrospect.

[SCT]

Wow, great info Mr. Hale. Just curious what degree of Vs did you consider in the origional design? Did the name "Black Max" come from the marketing department?

Thank you-

[rckid74]

Wow!!! I'm getting swamped with questions. I'm afraid that if I keep answering individual questions I'll never get back to the main story, so I think I'll just proceed on. Most of those questions will be answered in due time as part of the discussion.

[olboatman]

Thanks Mr. Hale for great informative and interesting reading----- You've got me hooked! Gary

[Hoss Marine Propellers]

Thanks Mr. Hale for great informative and interesting reading----- You've got me hooked! Gary

I'm hooked too!!!!!!

[petlun]

Wow, hot and exiting info indeed!

Had just planned to go to the cottage for vacation. But with poor internet-access, maybe I must stay home to read?

The only molecule of info I had of this so far, is someone loosely saying on this board several years ago that Ron Andersson started the design of the V6 in 1969. But now I guess that as well as other info will be put into an iteresting context. And did the decision for a looper design come already as an input from management? (And if so, an inline would have been taller than ever, right.)

Reviewing the V6-Merc history today, I think it´s rather relevant to see it as the "Small Block Chevy of the outboard world". Me myself still hang on to my I/L6 but sometimes, when my mind go soft, I´m considering pros and cons of a 150 ProXS instead of my 1988 I/L 115.

With high expectaions (but please take your time!)
Peter L.

[rckid74]

I still have the hand written spec sheet (wish list) that Bob Johnson gave me back in Jan 1970. I tried to include a copy of it here but it ended up so small on the page you couldn't read it so I'll just copy it word for word
OBJECTIVE: RAISE MAX. POWER 10% = 150HP.
1. A 10% displacement increase seems inappropriate - affords no room for future increases, bore increase
will increase deton. probs
2. 20% displ. will fit the 2 liter class + seems like suitable amt.
3. 2 7/8 bore (current 1350 size - ring etc) & 2.35" stroke (.050 more than M-1000) = 15.25 cu. in. 8cyl = 122 cu in
6cyl = 91.5 cu in , 4cyl = 61 cu in , 2cyl = 30.5 cu in.
4. Develop loop cyl. to avoid cross scavenged problems
5. V configuration lends itself to loop cyl. spacing as does an O. P. --
6. Capable of another 10% displ. incr. later - possibly bore only (3in. = 9%)
7. Seek lightest weight & smallest package size

That's it, exactly as given to me. So what was I to make of this? It's obvious that Bob is thinking - how can we get the greatest range of engines using the same piston, pin, rings, bearings, etc. Economy of scale, you know. But a 2 liter V8??? That didn't make sense to me. If we were doing this in part at least to be in a racing class (2liter), we certainly would want the highest horsepower we could get and that ment 2 banks of three cylinders with their inherent excellent power boost from exhaust pulse tuning. 4 cylinder banks don't give you this, at least not with any neat compact exhaust manifold. I'm not quite sure how I got Bob thinking my way. I believe I just kind of ignored the V8 thing and proceeded on with my analysis of the inline 6, the opposed 6, and the V 6, and Bob never said anything more about it. (more later)

[transomstand]

I still have the hand written spec sheet (wish list) that Bob Johnson gave me back in Jan 1970. I tried to include a copy of it here but it ended up so small on the page you couldn't read it so I'll just copy it word for word


Email it to me and I'll post it, and anything else you'd like to post.

[Glasstream15]

Let me just add my thanks for this history lesson. VERY interesting.

[rckid74]

OK transomstand, but I need your E-mail address!

[transomstand]

OK transomstand, but I need your E-mail address!

Sent you a PM

[Raceman]

Jerry, what a spectacular addition your commentary is to this forum and we really appreciate your contribution here. There're a couple of things I'd like to ask for when you get the time for individual comments or questions and maybe these too will fall in place as you chronology continues.

As far as Triechel (spelling?) I first met him on the phone when I was interested in collecting T4 stuff. (I have 3 complete T4's as well as some extra T4 & 3.4 EFI powerheads). Thriechel CLAIMED to be very involved in the T4 project and did seem to be very knowledgeable on them. He asked the displacement of mine, saying there were some built that were overbored and something like 3.7 or 3.8 liter. (I can't remember) He quoted some RPM numbers that they ran the sprint boats on, (can't remember that either) and said they replaced all the bearings including upper and lower ones, and rod bolts after every race because the big ole' rotating assembly would cause failure otherwise. He was also my first source of contact information with David Steckbauer who he suggested I call for my search for a #8 Speedmaster for the T4.

Back to the 2 liter, or specifically the T3 I'd like to know for sure the chronology. I bought an 18' Sidewinder from a local dealer in 1974 and he had a picture of what was PROBABLY a Molinari on the wall with a T3 on it, the first I'd ever seen. Instead of having the red T3/1750XS stickers it had a large blue T3 on the sides of the cowling. Since this was already hung in '74 I would guess the engine was probably some kind of prototype from '73. We went to the APBA nationals at Miami Marine Stadium in 1975 and all the V6 Mercs on the factory boats had the red T3/1750XS stickers and I don't think any privateers had 'em yet. I've also always heard that the T2X was built AFTER the original T3, which would make sense, since it was basically a T2 powerhead on a T3 mid with a adapter. True or false on chronology?

My dealer friend who also accompanied me to Miami that year for my first big time boat race claimed to work very closely with Carl Kiekhaefer in the 50's and early 60's, although I'm unclear as to what capacity. His name was Billy Dupree, and at the time he was based in Wisconsin. He later ran the proving ground in Sarasota. His son Wally, retired from Mercury also and now mid 60's worked at Sarasota as a teenager in the 60's basically as an endurance test driver and later at the distribution center in Atlanta as a service school instructor and later in warrantee. This was after the Duprees closed their dealership here in 1978. Wally has said on multiple occasions that when Merc was exploring the options on building a big inch race engine to compete with the V8 OMC that they built a V8 which was a 2.4 with 2 extra cylinders on top. He said that he has seen a running prototype in Wisconsin, but the engineers decided that the 60° firing order of a V6 was inherently more efficient than the 45° of a V8, possibly pertaining to the exhaust pulses. I've never caught him in a tale, but also have never run across anyone else claiming to have seen the V8 Merc. There were also some rumors of some prototype 3 cylinder loopers designed to compete in the Mod 50 class which was completely dominated by the OMC's, but that seems to be folklore also and until the time I quit going to the races OMC dominated everything in the 50 and 66 cu in classes.

Thanks again for participating and if my chatter above is distracting from your topic feel free to ignore any or all of it.

[Mark75H]

Fred Hauenstien confirms the 3 cylinder looper project, it was one of his jobs at Merc.

[T2x]

remember guys ...there was about a 7 year gap between the first V6 and the ill begotten 3.4 monstrosity...which was probably a bad project to begin with (it was too heavy for the existing center sections and lowers...and had a very limited consumer market...come to think of it so did the OMC V8's.....) The original toilet bowl manifold Bendix injected T-3's were magical alright, but this thread seems to be about developing the Black Max consumer motor...and not Les Cahoon's variations on that design.

[Scream And Fly]

What an absolutely incredible thread. Welcome to Scream And Fly, Jerry - we are greatful to have you here and extremely excited about this thread. I've already bookmarked it even on my cell phone so I won't miss any replies.

This thread has me really excited. Thank you for taking the time to post this fantastic material. This is the kind of stuff that we all share a great passion for.

Greg Terzian

[HStream1]

Thanks for sharing your wealth of knowledge with us Jerry!!! Welcome to Scream and Fly.

[transomstand]

I still have the hand written spec sheet (wish list) that Bob Johnson gave me back in Jan 1970. I tried to include a copy of it here but it ended up so small on the page you couldn't read it so I'll just copy it word for word
OBJECTIVE: RAISE MAX. POWER 10% = 150HP.
1. A 10% displacement increase seems inappropriate - affords no room for future increases, bore increase
will increase deton. probs
2. 20% displ. will fit the 2 liter class + seems like suitable amt.
3. 2 7/8 bore (current 1350 size - ring etc) & 2.35" stroke (.050 more than M-1000) = 15.25 cu. in. 8cyl = 122 cu in
6cyl = 91.5 cu in , 4cyl = 61 cu in , 2cyl = 30.5 cu in.
4. Develop loop cyl. to avoid cross scavenged problems
5. V configuration lends itself to loop cyl. spacing as does an O. P. --
6. Capable of another 10% displ. incr. later - possibly bore only (3in. = 9%)
7. Seek lightest weight & smallest package size

That's it, exactly as given to me. So what was I to make of this? It's obvious that Bob is thinking - how can we get the greatest range of engines using the same piston, pin, rings, bearings, etc. Economy of scale, you know. But a 2 liter V8??? That didn't make sense to me. If we were doing this in part at least to be in a racing class (2liter), we certainly would want the highest horsepower we could get and that ment 2 banks of three cylinders with their inherent excellent power boost from exhaust pulse tuning. 4 cylinder banks don't give you this, at least not with any neat compact exhaust manifold. I'm not quite sure how I got Bob thinking my way. I believe I just kind of ignored the V8 thing and proceed on with my analysis of the inline 6, the opposed 6, and the V 6, and Bob never said anything more about it. (more later)

Copy of the original document

http://i221.photobucket.com/albums/dd58/transomstand/Merc%20V6%20Project/Merc_V6_objectivecopy.jpg (http://s221.photobucket.com/user/transomstand/media/Merc%20V6%20Project/Merc_V6_objectivecopy.jpg.html)

[FUJIMO]

remember guys ...there was about a 7 year gap between the first V6 and the ill begotten 3.4 monstrosity...which was probably a bad project to begin with (it was too heavy for the existing center sections and lowers...and had a very limited consumer market...come to think of it so did the OMC V8's.....) The original toilet bowl manifold Bendix injected T-3's were magical alright, but this thread seems to be about developing the Black Max consumer motor...and not Les Cahoon's variations on that design.

Oh...o.k...we'll keep all that in mind chief...lol.

[FUJIMO]

Waiting patiently for your next installment Jerry. :smiletest: Don't want to ask any specific questions yet, as your chronologic input, I'm sure, will answer quite a few points. Great stuff. :thumbsup:

[Greg G]

That original document is a special piece of history and should be properly preserved. Thanks Jerry and thanks transomstand for the great repro. Wow!

[rckid74]

Thanks everybody for all your kind comments and encouragement. That really makes me want to put more time into this little bit of history. Now let's get into the meat of this design.
Obviously we didn't want a big, wide, bulky looking cowl like others had on the market at that time (after all, our heritage was that nice, slim "tower of power" the inline 6) and to me, only 3 configurations held possibilities of getting us close to that; another inline, an opposed with the cylinders running fore/aft, or a narrow angle V (60 deg was the only logical choice). I must tell you that I was strongly in favor of the 60 deg. V6 right from the start. True, there wasn't as much room between the banks for the exhaust system as a bigger angle would give and a few other minor negatives but the even firing order, the tight pulse tuned exhaust system, the carbs right up front, and the exhaust neatly down the back, to me, was the right choice. But my boss said check out these other ones as well, so I did.
In determining overall size, cylinder center distance is a major factor, and this wants to be kept as small as possible, that is if crankshaft strength is not adversly affected. I won't go into detail on that statement because loop scavenged cylinders, with their big teacup shaped handles sticking out on either side, generally provide plenty of room for crank web strength. Therefore I needed to concentrate on determining the shape and size of the transfers. Now I had never designed a looper before, in fact, my experience with cross-scavenging was limited to just the previous 5 years at Mercury, so I needed to improve my knowledge and decided to do that by obtaining and studying in detail the best loop scavenged engine I could find. The engine I decided on was the Husqvarna 360 motorcycle. This has a cylinder just about the same size as we'd be using in the 2 liter and from what I'd seen of it running in motocross races and enduros, I knew it had lots of down low pulling power as well as a broad torque band which were the characterstics I thought we wanted. So I ordered one and had it shipped to plant 6. When it got there I just had to take it out for a ride. I had my own 250 Bultaco Matador which I had ridden in a number of enduros around the state so I was comfortable on a dirt bike. But, wow!! That Husky was something else. If I was just tooling along in any of the lower 3 gears or so and grabbed a handful of throttle, that front wheel was coming up over my head in a hurry. I said, yea, that's what I'm looking for, lots of low speed grunt. BTW I read that this Husky was Steve McQueens favorite bike, I expect for the same reasons I liked it. (more later)

[mach351]

This is VERY cool!

[1FASTLASER]

This is so awesome. Reading history from the or one of the men himself. I'm all ears ....lol or eyes

[Dave Strong]

This is amazing info thanks so much for sharing.

Dave

[Mark75H]

This is great! Please continue :)

[njj502]

Scribed. Killer info keep it coming!

[Greg G]

Wow! Husky's and Bultaco's thrown in the "brainstorm bowl" of Mercury ideas. Very cool.

[1FASTLASER]

Yeah huskys and bultaco's......I remember them bad arse motorcycles very well. I use to run a bull. Back then as far as 2 stroke bikes they RULED. Lol now back to this awesome history lesson

[rckid74]

I think that before I go on about the production engine design I should clear up my relationship to the racing version. I had nothing to do with it. As far as I know that was strictly Ron Anderson with help maybe from a guy by the name of Ray Reid and Dick Lanpheer. By the time Ron was hired into my group (about the end of '71 or early '72) we were already running sand cast prototype engines. He was in my group and under my direct supervision for maybe 6 or 8 months before he was branched off to do the race engine. I'm quite certain this was just to get him familiar with the engine and to give him time to establish contacts within the company before he was turned loose to do his thing, and do it he did, ending up with the T2 or was it the T3, 2 liter race engine. I can't keep my T's straight anymore. As you probably know, Ron's background was as a boat racing driver, engine tuner, and prop expert and I'm sure that's what he was hired into the company to do. Hell-of-a-nice guy and personal friend. I believe he moved out to Australia some years back. You racing guys should try to make contact with him and see if he won't do a write up like this about the race version. That would be very interesting.

[Dd24skater]

This is the best thread I have seen in years! Awesome!!

[Glasstream15]

This is the best thread I have seen in years! Awesome!!

At Least. Thanks again for this great lesson in history. And thanks to S&F, without which, we wouldn't have this opportunity.

[Greg G]

Ron Anderson with help maybe from a guy by the name of Ray Reid and Dick Lanpheer. By the time Ron was hired into my group (about the end of '71 or early '72) we were already running sand cast prototype engines. He was in my group and under my direct supervision. Hell-of-nice guy and personal friend. I believe he moved out to Australia some years back. You racing guys should try to make contact with him and see if he won't do a write up like this about the race version. That would be very interesting.

Man the good info just keeps flowing, thanks. I thought there was a Merc Ace Ron Anderson in the Seattle area. Can it be the some one?

[native2]

Great stuff!! Thanks

[T2x]

Great stuff.....It would be interesting to see how the Merc V6 development compared to OMC's efforts. The greatest part of this is the way it started from a single sheet of notes rather than from reams of data... To me the best projects are visionary and not from data driven committees.

[fox88gt]

Best thread on the site in years. I've been patiently waiting and hoping that this thread would come alive. Thank you very much! JB

[rckid74]

I'm having trouble again with this site rejecting my entries. Lets see if this goes thru?

[transomstand]

Easy, create any text then highlight it by holding the mouse button and draw the curser across the text. Then right click as shown and click on cut. That copies it to your "clipboard", then to reply to a post, right click again and select paste, and the cut text will appear in the post.

http://i221.photobucket.com/albums/dd58/transomstand/A%20uploads%202013/paste.jpg (http://s221.photobucket.com/user/transomstand/media/A%20uploads%202013/paste.jpg.html)

[rckid74]

Back to the design. ---- After riding the Husqvarna for awhile to get a good feel for it’s power characteristics, I had the engine pulled and put on the dyno. As expected, it had an excellent BMEP curve. BMEP is the average pressure in the cylinder during the expansion stroke and allows you to directly compare engines of different sizes. My measure of a strong, tractable engine is one that has at least a 4000 RPM spread with the BMEP being over 100 PSI. We’re talking 2-stroke engines here. Next I stripped the engine down, cleaned up the cylinder, and made RTV castings of the transfer passages. They were beautiful. Nice big handles swooping way out then smoothly curving back to the port while gradually decreasing in cross-section. Just what I would like to do in the new engine. The only trouble was that they stuck out nearly 2 inches beyond the cylinder wall on each side and while this was fine for a single cyl engine they would just not fit compactly into a multi-cylinder. What to do? What to do?
I had read an SAE paper #680468 titled “Scavenging and Other Problems of Two-Stroke Cycle Spark-Ignition Engines” written by a German engineer named Alfred Jante. In it he discusses a technique he developed for evaluating transfer passages and ports in 2-stroke engines and looked like something I could use to help me scrunch down those big transfers while still maintaining good flow patterns. In his test the cylinder has the head removed and the piston at BDC and is mounted on a fixture which allows you to blow air up thru the transfers. A row of pitot tubes is stepped across the open cyl top and a plot is made of flow velocities over the entire top of the cylinder. This is then analyzed and compared to known good patterns, changes are made and reflowed until a good pattern is achieved. (more later)

[RBT]

I feel like an addict, I stop everything to get my fix when the notification comes that there is an update, only possible improvement would be to add Mr. Anderson for the race versions once this is complete.
RT

[Scream And Fly]

I feel like an addict, I stop everything to get my fix when the notification comes that there is an update, only possible improvement would be to add Mr. Anderson for the race versions once this is complete.
RT

I know exactly what you mean, Rob. When my phone beeps with a reply notification, I stop what I'm doing and instantly read this thread (if I'm not already at my computer, of course).

Greg

[Dave Strong]

Greg this needs to be a sticky.

Dave

[Awl Trimmed Out]

:iagree: It's just way too cool to get caught up in the other threads.

[JFL]

Jerry, I have Old Blue in my garage, want it back?

[rckid74]

What!!!! I don't believe it. You have Old Blue!!!! I'm planning to tell the story of Old Blue later in my narrative. I'd love to have her back but then she would probably just sit out in my garage from then on. She really deserves to be put in a Mercury place of honor for all to see, like maybe the lobby down in Fond Du Lac. Hopefully someone from Mercury will see this and contact you. If not, I will certainly take her. For those of you who don't know what we're talking about, Old Blue was the very first sand cast V6 we made during this program and was the strongest, most durable, best engine of the bunch. Many, many tests of all kinds were run on her and she never faltered. Thanks for taking her in to keep her from the scrap pile.

[1FASTLASER]

This is just way to unbelievable ....this kind of history AND the original. WOW !!!!!! Please someone post a pic!!!!!!

[JFL]

She was destined for the scrap heap in Oshkosh during one of Wilbur's clean up campaigns, I sent it to the Lake to save it. When the Lake closed she went home with me. She has an inline 6 driveshaft housing and gearcase, 4 cylinder OMC carbs, the distributer hanging off the side of the block, and still has the rust stains from the PLT 6 test tank. The poppet valve and other things are remotely mounted, there maybe other parts missing, and there is no cowls. The adapter plate is hand made V6 to inline 6. It also bas plastic windows in the side of the reedcages to photograph the action of the reeds. I also have all the Lake X test request log books from 1963 to 1978, which includes the endurance testing of the 951. Now that I am retired , they are for sale.

[njj502]

Instead of selling them I'd suggest just giving them to someone and charge them the last few decades of rent. This will probably keep the corporate clowns from harassing ya.

Jus one corporate guy looking after another....

[John Schubert]

This should go to Rich Luhrs or Sam Cullis.

[FUJIMO]

John, Yes...I agree these need to be passed on to someone of honor, with the capacity to correctly preserve them, such as the likes of Sam Cullis(aka Mark 75H), or our very own Greg Terzian, of Scream & Fly.

[RBT]

Somewhere in here I feel like there is a picture of a v6 on a inline mid, or a discussion about it.

bottom line is we need PICTURES

[JFL]

I don't have to worry about the corporate clowns anymore, I retired from Mercury May 24 and started with Seven-Marine June 3rd. After 45 years , no regrets just fond memories and a lot of good friends. Time to make new friends all over again. JFL

[Quinten]

Mmmuuuuussst subbbbbscrriiiibe!!!!!

[njj502]

Great transition!!!! Need a lonly ole product support guy that's got yeller tractor background? :D

[Chummy]

Somewhere in here I feel like there is a picture of a v6 on a inline mid, or a discussion about it.

bottom line is we need PICTURES

Yeah thats a friend of mines motor that i posted some pics on here a while back

http://www.screamandfly.com/showthread.php?168668-A-strange-one&highlight=

[rckid74]

Back to the design --- Before I could get on with the evaluation of the three different cylinder configurations, I really had to know what the minimum cylinder spacing could be. Therefore I decided to build my own “Jante Fixture”, (as it later became known), so I could experiment with different transfer passage and port shapes which would allow relatively close spacing. The model shop made the parts and I put them together and set up my fixture in a little room there in plant 6, not much bigger than a closet, but where I could be alone and not be bothered by phone calls, etc. For the air supply I used the pressure side of an old canister vacuum from home, that my wife didn’t like, and controlled its’ speed with a variac voltage regulator.
First, I flowed the Husky cylinder, and, as per Jantes’ paper, it had an excellent pattern. This would serve as my reference to strive for. Then I built a fixture with removable side pockets in which I could insert RTV molded passageways of differing shapes to simulate the passageways for the new engine. I played with different shapes for a solid month, sometimes moving forward, others back, until I was finally happy. I found that it was relatively easy to get a good pattern but very hard to get one and at the same time have a very low restriction passageway. I also had to take account of the fact that the parting line for the production molds would pass right thru the transfer port and so the sides had to have at least minimum draft. In the end I had compacted down the transfers and then rotated them about 30 degrees so adjacent cylinders could nestle together to a cylinder center distance of 4 3/8 inches with the 3 1/8 inch bore. This is what I would base my rough layouts on. (more later)

[bernie]

On an email from JFL today, he sent pix of Old Blue. Here they are:278859278860278861

[Capt.Insane-o]

How cool is that.

[Glasstream15]

How cool is that.

Cool?? That is FRIGID. This whole thread is just absolutely .... Incredible doesn't do it justice.

[1BadAction]

On an email from JFL today, he sent pix of Old Blue. Here they are:278859278860278861
Wow!

I had to look at this three times to realize what it was. :eek: Amazing.

[native2]

Sitting upside down balanced on the flywheel.... We should find an engine stand for Old Blue... She deserves it. :)

[Hoss Marine Propellers]

278860

OK.... Here's a question ...... What's the white box/item located on the throttle arm?

[Mark75H]

On an email from JFL today, he sent pix of Old Blue. Here they are:


Wicked!

[transomstand]

Looks like an old school ballast resister,for bringing voltage down.

Yep, no switch boxes.

[lilabner]

Raceman: I just hooked on to this thread and saw your post about Billy Dupree.. He was the real deal. One of Mr. K's right hand men. I heard he was hired on for the NASCAR project, along with a big guy with black hair that could spin a lug wrench faster than anyone. Can't remember his name here in the fog..Gene Lanham or Olgator might. Billy was the factory rep for the dealer I worked at in 58-59 in South Miami. Everyone liked him..I didn't see him much after 59-60. He may have left the company.

[JFL]

Spark Plug wire holder.

[JFL]

This one used the IL 6 ignition system, switch box was remote mounted

[Capt.Insane-o]

It would be really cool to see that run again

[blkmtrfan]

Awesome thread, please keep it coming :thumbsup::thumbsup: And I am with the capt, Old Blue needs to run again :cool:

[Hoss Marine Propellers]

Spark Plug wire holder.

Thanks ..... That makes sense now ..... plug wires coming out of distributer and heading to back of engine. :iagree:

[HStream1]

:iagree: Have patience guys. There are a few PM's addressing this very issue and we will see what transpires ;).


Awesome thread, please keep it coming :thumbsup::thumbsup: And I am with the capt, Old Blue needs to run again :cool:

[rckid74]

Since we’re talking about “Old Blue” I guess I’ll tell you more about her. This is getting a little ahead of the story but I guess it fits in.
When we got the first block casting from Eck Foundry, which must have been somewhere around mid ‘71, the shop foreman decided he wanted to do a complete layout on it. He didn’t want to get part way machined only to find out there wasn’t enough stock on some area, so he had it completely sprayed with blue Dykem layout fluid. I suppose it would have been hard to remove after machining so we just had a blue block and at some point along the way we got to calling her “Old Blue”.
Now I wanted to get her up and running as fast as possible because I had learned from past experience that upper management often changed their mind about projects and would cancel them if they had the slightest doubt about it. They could be very fickle. So if there were certain parts I couldn’t get to build those first engines, I used whatever would work. For instance, our carbs from Tillitson were a long way off so I used OMC V4 carbs instead. The reed blocks were from a West Bend engine. The entire ignition system was stock Merc inline six with belt driven distributor. In fact , it was originally intended to go into production with the distributor but that was all changed over at the last minute to the 6 coil setup which caused a significant delay in production startup.
Anyway, we got her built up, put her on the dyno, pushed the starter and she fired right up. That’s always very satisfying to have a brand new engine do what its supposed to right off the bat. Ran her for awhile at low throttle settings and then took her off and tore it all down. I wanted to see if there were any areas showing distress. Everything looked good so we put her back on and proceeded with our test program. Peak horsepower was about 155 at a modest 5000 RPM. I had purposely kept the exhaust ports low for starters because it’s a lot easier to take metal off than to put it on. At some point later in the test program it was decided to up the port timing and see what she would do. We notched the piston leading edge to do this. The first cut produced 175 HP at about 5500 RPM and another gave 204 HP at just over 6000 RPM and still climbing. She really responded to exh port timing.
Old Blue went on to have many tests of all types run on her but eventually, as production hardware came online things shifted away from the early sand cast engines and she took a back seat. At some point there she disappeared and I lost track of her and assumed she had been scraped out.
About 20 years later (1995) I was working on Mercurys’ ill-fated PWC project and they had moved the group into plant 64 over on the Fox river in Oshkosh. The building had been essentially vacant for some time and was being used mainly for storage. One day I was down in the basement area looking for something when I noticed off in a dark corner an engine on a pushcart that looked familiar. As I got closer there was Old Blue. I couldn’t believe it. She looked terrible. Her heads were missing. There were tubes and wires hanging all over, obviously from the last test that was run on her. But there was Old Blue. She had survived.
Well I couldn’t just leave her like that so I took her upstairs into the tech assembly area and spent several lunch hours cleaning her up. I lubed up the cylinder walls, turned the crank several times to spread it around. I couldn’t find any sand cast heads to put on but I made some calls to the service people and they came up with a couple diecast heads that fit. These had to have the bolts on the cylinder wall like all the early engines. I cleaned her up as best I could but then didn’t know what to do with her. Shortly after that the entire group was moved to Hartford where the PWC production line was being set up. I didn’t want to take Old Blue down there for fear she would eventually get scraped out. So I left her there at plant 64. Apparently that’s where JFL found her and you know the rest of the story. I hope she eventually finds a proper home.

[JFL]

How do you like the pictures? Does it look like the last time you saw it? We need to talk.

[Capt.Insane-o]

How far along the line did the adi ignition come into play?

[lilabner]

I'll try to clear some of the fog. You have Billy Dupree mixed up with Chick Morris. Chick worked with Frank Mundy on the race car when he was hired. He was our factory rep also. He moved up with mercury. He became the branch manager of the Atlanta branch and retired from there. I know Billy has told me how he started with mercury but can't remember the story now. Billy was a long time employee and very close to the old man. when the old man wanted a mercury presence in Kissimmee, Billy was the front man. Billy was like a second father to me.
I don't think I have them mixed up too much. I remembered Chick's name while trying to go to sleep. He was our factory rep for awhile also, but not for long. He may have been before Billy. I worked at Dade Marine from about 57 to 64, with a little over a year in between with Dave Craig. Chick was the tire changer. I think it was Dave that told me about the two of them. Billy would go drinking with Ken Wilson, boss at Dade Marine from 60 on till Leonard took over. I figured you would know about them also. Billy seemed to fade out down south around 60..

[rckid74]

Perhaps before I get too far along I should try to answer ‘Rotary John’s’ question from back on page 1 as to why we were apparently shooting so low with our horsepower goal of only 150 HP. Now I must say that most of what I’m going to say here is purely conjecture on my part. I was not privy to the goings on at the upper levels of the company so I just kept my nose to the grindstone and tried my best to achieve what was asked of me.
When I first came to Mercury in March of ‘65 the engineers at plant 6 were just finishing testing a somewhat larger (135 cu. in.) cross flow inline 6. It never went into production for reasons unknown to me but I heard that one of the major objections was that it was just too tall. I think it was like 3-4 inches taller than the M1000 then in production and that was not acceptable. But this indicated to me that they were concerned about future power increases to keep up with or ahead of the competition. The M1000 could be stretched a little further and we bored it out and bored it out some more and kept upping its power, and then Herman Maier came along and worked out the Direct Charge system which gave us a little more breathing room, but it was obvious we needed a basically bigger engine with room to grow, an engine that wasn’t so tall.
Now it’s fairly well known that Mercury and OMC had been having a horsepower war for many years with Mercury usually leading by 5-10 HP or so and we intended to keep it that way. By 1970 we were up to 135 HP and OMC had what, maybe, 125. So when Bob Johnson handed me that spec. sheet requesting a 122 cu. in. loop scavenged engine with room to be bored out another 10% and a power rating of only 150 HP, I’m fairly certain he was thinking that would be enough to counter OMC’s next move and then we could easily keep moving up as need be. Little did we know what OMC had in store for us. More about that later.

[T2x]

RCkid: The HP figures you are quoting were at the crankshaft rather than propshaft...correct?

[Scream And Fly]

I would very much like to make sure this thread remains very visible for all readers. Perhaps eventually we should have this article accessible right from the home page too? This discussion is incredible.

Greg

[Hoss Marine Propellers]

I would very much like to make sure this thread remains very visible for all readers. Perhaps eventually we should have this article accessible right from the home page too? This discussion is incredible.

Greg

I Agree :cheers:

What you might consider is just allowing this thread to continue along & make it a "sticky" and then have an "edited" version also available from
the home page without all the extra comments ...... just the "good stuff"? That way, anyone new could read the "meat" of the conversation without having to read page after page of comments. ...... of course, if they wanted, they could also read the entire posts of this thread. (not trying to say other's posts are not important to the thread, just the extra comments that take time and really add nothing to the thread.... like this post and Greg's previous post.) :eek:

[Cp]

I am in total awe of the original Merc V6 engineer recounting his development cycle. I worked on some 'stuff' at a large computer company for too many years and none of that would compare to the results and pride you have in the device you created over forty years ago.

I mean this sincerely: Thank you for your devotion to developing the technology that makes us look forward to next weekend.

[olboatman]

:iagree: With CP This is what we live for concerning boating! Gary

[rckid74]

To T2X. Yes, back then all power figures were based on crankshaft readings. It wasn't until some years later that we started rating at the propshaft.

[olboatman]

To T2X. Yes, back then all power figures were based on crankshaft readings. It wasn't until some years later that we started rating at the propshaft.

Your correct if I'm right the propshaft readings started in 1984. Gary

[FUJIMO]

;)

What you might consider is just allowing this thread to continue along and then have an "edited" version also available...
without all the extra comments... That way, anyone new could read the "meat" of the conversation without having to read page after page of comments. ...... just the extra comments that take time and really add nothing to the thread...:eek:

Couldn't agree with you more...

[Dave Strong]

This is just getting good.

Dave

[JFL]

I remember the first time we ran Old Blue on a boat at the Lake. Probably about November of 73. It came in this big upright wood box, it had a plastic drop on cowl that was padlocked to the lower pan. The control box, cables and fuel line all were attached to the engine. All we had to do was mount the engine, screw the control box to the side of the boat , fuel and battery. When it hit the water we couldn't believe the power and top speed. Remember we could only compare it to the engines of the day, maybe 135 HP, this thing was much faster. The next day we crated it back up and sent it back to Plt 6. I can safely say I was one of the first people in the world to drive the first Mercury V6. The other person was my brother Jack.

[Greg G]

When you say your brother Jack, the last name does not happen to have 4 letters in it?

[pointer]

Thank You so much for this thread!
Agree on having an edited "good stuff sticky"!

Absolutely amazing that this has the content it does - again THANK YOU!!!

pointer

P.S. My dad had a 71 or 72 115 tower we ran until 1986, replaced with a 135 V6. I can remember the first V6 1750 locally. To think the V6 was being developed while we were chasing fuel starvation issues on delivery of the 115 is hard to comprehend. Once we got the fuel issue resolved we were one of the fastest rough water boats on the river at 42 - 45 MPH. The change to the V6 135 added 10 MPH... :)

[Da Bull]

I just started reading this thread and am amazed. I to will be checking in on this every day. Us gear heads are like a sponge for information about the history of our sport.


My first new motor was a 122ci 175 that i paid $2,800.00 for in the box. Took it home, did the install and never had one second of trouble with it. I think it was the best motor i have ever owned thanks to our new friend Mr. Jerry.

DB

[kb5050]

subscribed

[milkdud]

I find this very interesting. That adaptor plate putting Old Blue on a L6 mid is nicely done. Did you have to make a special exhaust tuner for Old Blue or did the L6 tuner work?

Its interesting to know how far back development went for the V-6. Also interesting to know that Mercury did not sit on there hands with the L6 as the V6 was being developed. 1970 1972 and 1973 were all notable design advances for the L6 regarding piston design and exhaust design.

You were around some of the coolest 6 cyl motors made. From 89 cubes to 93 cubes to 99 then your V6 122.

Thanks
Conrad

[milkdud]

1976 Mercury AD

"The Black Max was 6 years in the making" from the ad.

[milkdud]

1977 Mercury AD

[brianscathouse70]

Who is the guy in the ads? 2 yrs with same guy. Was he someone important?

[mbd29]

His name is Len Yeager. If I remember right he had a guide service in the Ozarks somewhere. He used to go to all the shows as well as Mercury functions. I believe he is still alive. Haven't seen him in years.

[JFL]

No, it has seven

[JFL]

When we first started testing this engine , it was so secret, that we had big wood boxes over the engine all the time. We were not allowed to back it into a slip for fear that the OMC boys would drive by and see something. Remember that Spellman's was an OMC dealer. I know that Boots didn't care what we built, he may have known anyway as we were always racing past his marina on the Fox river. But the secrecy was out of sight , we couldn't even tell our families about it. When ever we worked on the engine, we had to keep the shop doors closed so no one could take a picture. JFL

[JFL]

Got it probably not going to happen

[1FASTLASER]

I can't wait to hear my notification sound from my phone on this thread. This is huge

[tired creek marine]

I will be looking forward to your next post.

[T2x]

Who is the guy in the ads? 2 yrs with same guy. Was he someone important?

He was supposed to be "Black Max" for promo purposes....Like the "most interesting man in the world" in today's "Dos Equis" ads (who, in fact, is a California guy originally from NY if I am not mistaken).

[FUJIMO]

David...waiting patiently for your next installment. Hopefully you will soon get to the cooling system & its excellent design, for which you hold the patent(s) on. Down the road getting into your patented(along with Kollman & Mayer) 1750 trim system, including the hydraulic lower mounting bolts/fittings, etc., as well. Thanks once again. Everyone should enjoy this. Great stuff.

[JFL]

The trim system with the hollow bolt were a pain, try to keep the silicone sealer out of them, and when they galled, good luck getting them out. We made a puller to jack them out with a slide hammer, because we changed engines all the time. We also used regular nuts so we would not stick them. The steering system was also not cool, as the tilt tube was over the top of the transom. When we needed dual cable steering, there was some engineering involved, which was not simple or effective. You needed dual cable because the engine had a LOT of steering torque because we started using the Alpha 1 gearcase, after a while we had to change the gearcase quite a lot. JFL

[JFL]

Who are you?

[rckid74]

Getting back to the design --- Having established that the cylinder centers could be 4 3/8 inches I could start the rough layouts of the three 6-cylinder engine configurations. The inline six was easy. It was obvious that with loop scavenging passageways the engine height would be even taller than the bigger cross scavenged engine which had been rejected before, so we eliminated it from consideration right away and proceeded only with the 60 degree V and the 180 degree V (opposed).
I had already set the bore/stroke ratio at 1.18 by making a listing of B/S ratios of 19 up-to-date loop engines which ranged from .927 to 1.22 and then staying within the range. I had leaned toward the bigger bore ratio mainly because this would allow a slightly narrower engine in the 60 degree V and I was determined to keep the engine as narrow as possible. Also, the shorter stroke would allow the engine to rev higher while keeping piston speed down. To get the required 10% increase in displacement, I would leave room for a bore increase from the original 3 1/8 to 3 ¼ inches. This would take the B/S ratio up to 1.22. Little did I know the bore would eventually go to 3.5 inches and a B/S of 1.32.

[Da Bull]

Mr. Jerry, I know this question is most likely premature but what was the purpose of the bridge in the transfer ports? They are prone to break in the chrome bore 2.4L and i simply removed them. I never broke one in the steel sleeve 2.0L.

[rckid74]

The bridge across the transfer passage is there to accelerate the flow as it makes the bend into the cylinder. This prevents detachment and turbulance which would restrict the flow. It worked well on the original bore of 3 1/8 but with the 3 3/8 bore I think it got somewhat thinner and less effective. I was off the project by the time we went to salt cores and chrome plated bores.

[T2x]

The bridge across the transfer passage is there to accelerate the flow as it makes the bend into the cylinder. This prevents detachment and turbulance which would restrict the flow. It worked well on the original bore of 3 1/8 but with the 3 3/8 bore I think it got somewhat thinner and less effective. I was off the project by the time we went to salt cores and chrome plated aluminum.


In those days how did you measure flow changes from one shape or layout to another? How much was on paper and how much was prototyped, and how many variants would you try and discard?

[rckid74]

Go back and read my comments on using the "Jante fixture". I probably went thru a couple dozen different shapes before being happy with it.

[T2x]

Go back and read my comments on using the "Yante fixture". I probably went thru a couple dozen different shapes before being happy with it.


Thanks, I appreciate the response.

[Hoss Marine Propellers]

Go back and read my comments on using the "Jante fixture". I probably went thru a couple dozen different shapes before being happy with it.

Page 6 - Post #76 (for anyone looking for the post?)

[T2x]

Page 6 - Post #76 (for anyone looking for the post?)


Got it thanks......

[rckid74]

Also read post #59 on page 4.

[rckid74]

After setting the (bore -3 1/8 in. and stroke -2.65 in.) to give the 2 liter displacement, the next thing to do was to determine the best crank arrangement. With six crankpins there are many different combinations to consider, however, if we apply a couple of restrictions it boils down to only four arrangements for each type (V and opposed). Those restrictions are that the firing intervals must be even ( for smooth torque delivery), and that the three cylinders of each bank must fire 120° apart (for exh. pulse tuning). These types were analyzed for balance and results tabulated. The technique used was to obtain complete balance data for a three cylinder inline engine firing from top to bottom and bottom to top and then vectorially adding the out-of-balance forces (couples in this case) for the two banks making sure to phase the couple vectors properly. Then it is easy to determine; first, if a counterbalance couple added to the crank can reduce or eliminate the inherent couple, and also exactly how much and where to place it. I did all this graphically as opposed to analytically. Today you would punch a few numbers into a computer and have the answers immediately. My computer back then was a slide rule, which I still have by-the-way.
Using this information I picked out what I considered to be the best arrangement for each engine type. (more later)
　

[Da Bull]

The bridge across the transfer passage is there to accelerate the flow as it makes the bend into the cylinder. This prevents detachment and turbulance which would restrict the flow. It worked well on the original bore of 3 1/8 but with the 3 3/8 bore I think it got somewhat thinner and less effective. I was off the project by the time we went to salt cores and chrome plated aluminum.



Thank you, Finnally after all these years an answer to my question. And an inteligent one at that.

DB

[Dave S]

Thanks Rckid for getting us away from the twisty L6 motors....I knew a smart man did the V6 merc.....I back engineer.......I allways thougt the 55 omc looper was the pre leader of the Merc V6.....just good engineering ????? C Strange was GOOD....

[99fxst99]

Man this brings back memories. We rigged the first 1750 in this area on a 15' Allison bass boat. The owner was not happy with it as his brother had the same boat with a 200 Johnson, and smoked him. I got the engine (maybe 10 hrs on it) and all the rigging for $1800 and rigged it on my Ventura II. The early engines had a stern drive shaped lower unit that blew out around 80 on the 'stream. We had it on display at the local boat show and the Mercury dealer brought the Merc rep over to see it. (the motor came from a dealer in North Carolina, no dealer in our area had gotten one yet). The rep looked at the boat, listened to me complain about the blow-out and took my address. Shortly aftyerwards, a new housing arrived UPS at no charge from Merc with the streamlined shape similar to the 1500. We ran close to 90 with that rig, and it was VERY user friendly and trouble-free for 3 seasons of river racing, ski racing, and OPC racing. Thanks to Rckid and the others involved for the "small block Chevy" of outboards!!!!

[rckid74]

Having calculated the balance situation for each of the crank pin arrangements and considering how those arrangements affected the requirements for crank strength, I picked one crank for the 60°V and one for the 180°V.
The one I picked for the 60°V was not the one with the best balance, however it does have adjacent rods on the same pin which makes the crank stronger, stiffer, and easier to machine, and allows for less bank offset which reduces size and weight. The balance was still somewhat better than that for our production in-line six. This crank also fired both banks from top to bottom or bottom to top which I felt might have beneficial tuning effects.
The 180°V crank chosen was the one with the lowest out-of-balance because the others were seriously out-of-balance. However it does not have adjacent rods on the same pin. Rods 1 and 2 are 120°apart, 3 and 4 are on the same pin, and rods 5and 6 are 120° apart. Also, one bank fires up, the other down.
Having made these basic decisions, a rough layout was made of each engine to determine overall size and also to investigate possible difficult details regarding the plumbing of exhaust and inlet systems, cylinder porting space requirements, sealing arrangements between crankcases, center main bearing support, and counterweighting means.
Certain advantages were found to be inherent in each design. These were:

60°-V6
1. Strong, stiff crank easy to machine
2. Fires both banks in same direction.
3. Exhaust is compact and flows smoothly into driveshaft housing. Easier to
tune exhaust.
4. Exhaust system has fewer parts and less machining.
5. Height and width are about the same as Opposed but length is 2 to 3 inches
Shorter.
6. Intake system is shorter and more direct.
7. Weight should be a little less.

180°V6 (opposed)
1. Inertial balance is better--.87 vs. 1.20.

Probably the biggest negative for the opposed engine was the difficulty of routing the exhaust from the front bank back into the driveshaft housing.

It was obvious, the 60°V was the way to go. So we (Al Tyner and I) started the detail layout. This would have been about May1970.

[Mark75H]

So, you never considered the paired opposed design (3 crankcase sections rather than 6?) as used by Konig and some others?

[rckid74]

So, you never considered the paired opposed design (3 crankcase sections rather than 6?) as used by Konig and some others?

I'm not familiar with that layout. Please explain.

[Mark75H]

Opposed cylinders on 180° crank pins, firing together. That's the way the antique opposed motors were set up and the way Dieter Konig built a few 6 cylinder race motors in the 60's (based on extension of his 4 cylinder boxers). It would seem like it would have a great volumetric efficiency advantage on a 2 stroke.

I understand the exhaust plumbing issue with the opposed motors; I would have solved it by not taking the outlet off the bottom, but I can see that the boxer would still stick into the boat more than other designs.

[rckid74]

Firing opposed cylinders together doubles the peak torque on all the driveline components and would require much beefier components, especially the gear set. It was estimated that the torpedo diameter would have to increase by 20-25% for equal life. I had eliminated this possibility when I required only even firing orders. I.E. 60-60-60-60-60-60-. Other than that, handling the exhaust from the front bank, as I said before, would be ugly. Dieter always just had tuned pipes jutting out in all directions which was fine for the racing classes but would not be acceptable for a production engine.
Why would your setup have any greater volumetric efficiency?

[Mark75H]

The internal tuned 3 cylinder stuff is running away from the external tuned pipes in Mod these days ... pretty sure I've figured out what the guys are hiding inside their neatly polished 3 cylinder exhaust housings ... to bring 3 pipes to the same length, 2 (1 & 3) run immediately to the front, the third (cylinder 2) first runs to the back, then turns around and goes the front - giving the same lengths at the point of convergence

Seems like the 2 pistons coming toward each other (& the crank) decreasing the crankcase volume from both sides at once could give a high primary pumping ratio

Now I understand about the high peak torque, Dieter built a double driveshaft lower unit for the 6's and still had a lot of trouble. It also explains why I've been getting away with smaller lower units running a 6 against the triples and why the triple guys are absolutely punishing lower units.

[puddlejumper]

this is great. I am getting ready to buy a 2.5 mariner and find it absolutely amazing to see the history of this motor unfolding before my eyes.

[mouse4x4]

this is great that all these different guys are coming out an sharing there own part in this keep it coming

[Da Bull]

Anything new about old blue?

[Scream And Fly]

This thread is so fantastic and so important that I felt it really needed to be pinned to the top of this forum, so everybody will be sure to see it.

Thank you to all of you that have contributed to this incredible resource of information.

Greg

[HStream1]

I couldn't agree more Greg!!!

BUT???
Why did it stop all of a sudden is my question? The two guys that were originally involved were on a roll and simply stopped? I hope it wasn't because of everyone bombarding them with questions before they finished their history of the Merc V6.

Please continue RCKID74 & JFL. Please!!!!!!!

[pointer]

I couldn't agree more Greg!!!

Please continue RCKID74 & JFL. Please!!!!!!!

Agree!!!

pointer

[transomstand]

How about if we make them honorary Heathens????

Maybe they're just on vacation.

[Onetime]

I've been holding off saying anything really hoping the moderators would act appropriately.

I hope it's not a health issue with Jerry.

But it's a Merc V-6 thread and people are asking why you didn't design it like this or that, how did you figure this when it was previously covered in his prior posts.

I felt some of the posts were insulting to the engineer who created this engine. Ever notice the ones with the most knowledge end up not posting? Here we have the designer of the Mercury V-6 willing to tell us the story and rather then letting him post the story people are taking it off track. Maybe this impresses themselves but I and many others were thoroughly enjoying the history and the story.

Jerry I hope all is well with you and I hope you continue. If you do start to post again I hope the moderators can keep it on track and allow you to tell the story without a bunch of BS.

There I've said my piece and anybody who wants to bash me for it have at it

[Dave Strong]

How about if we make them honorary Heathens????

Maybe they're just on vacation.

They might not want to be heathens. :eek::D
But getting real these guys have provided some amazing info and I would love to see it keep coming!!! :thumbsup::thumbsup:

Dave :)

[Old boy]

I personally feel the Moderators should have "locked" all other members out of this thread from the very beginning.
Perhaps the two original people may have kept writing this wonderful piece of history.
I pray they do continue.

Cheers.

[olboatman]

They might not want to be heathens. :eek::D
But getting real these guys have provided some amazing info and I would love to see it keep coming!!! :thumbsup::thumbsup:

Dave :)

:iagree:Well said! Gary:thumbsup:

[transomstand]

They might not want to be heathens.


I can't even comprehend that:nonod:

[Dave Strong]

I,m hoping it as was said above and just holiday season and the great info continues.

Dave

[Mark75H]

I'm sorry I asked a question, but that is how I learn things ... I ask someone who knows more than I do.

If the moderators feel it would be useful, feelings will not be hurt if my questions are deleted from this forum.

[HStream1]

I don't think anyone doesn't want to ask questions. I have a ton. But in a case like this being so rare!!! And we may never have the chance to hear it again. One must allow the Insiders of the history of the all famous V6 to be revealed. Then Bombard them with questions. Just My 02.

It's not so much about the moderators as it is all of us allowing the guys to tell their story without interuption. I myself am at fault and and I appoligize. I would love to see this rare piece of history get restored for all to appreciate.

I remain silent from this point on.

[Onetime]

Let's just move on and hope Jerry posts more.

[tired creek marine]

I look forward to hearing more about the v6, right up to the efi, and opti-max. Sence 98 the blocks have not changed much, yet the intake and operation is great.

Well I will be silent, and look forward to more wisdom from two great minds.
Thank You for your excellence.

[rckid74]

Sorry guys, I’ve had to attend to some personal matters for awhile here and haven’t been able to continue with “Black Max”. I hope to get back to it soon.

[Murph]

Appreciate all the effort.

[transomstand]

Sorry guys, I’ve had to attend to some personal matters for awhile here and haven’t been able to continue with “Black Max”. I hope to get back to it soon.

Hope all is well, let us know if we can help in any way.

[Speedfab]

Sorry guys, I’ve had to attend to some personal matters for awhile here and haven’t been able to continue with “Black Max”. I hope to get back to it soon.

Yes PLEASE do. There are many of us out here who appreciate this immensely and enjoy it very much. I too am an ME and have spent my life in the performance engine business... I could think of a million questions to ask you, but I intentionally did not want to write anything here that might crap up this thread. Please continue, there are many more like me out here who are quietly watching this thread anxiously awaiting the next piece of the story.

Thank you very much for taking your time to do this.

[olboatman]

Yes PLEASE do. There are many of us out here who appreciate this immensely and enjoy it very much. I too am an ME and have spent my life in the performance engine business... I could think of a million questions to ask you, but I intentionally did not want to write anything here that might crap up this thread. Please continue, there are many more like me out here who are quietly watching this thread anxiously awaiting the next piece of the story.

Thank you very much for taking your time to do this.

:iagree::iagree::iagree:Well said! Thank You rckid74. Hope all is well. Gary

[milkdud]

Great thred. Hope it can get back on the air.
C

[rckid74]

OK --- Let’s get on with designing “Black Max”. That name, BTW, I believe was dreamed up by someone from marketing (I don’t know who) late in the program. I remember Bob Johnson called me into his office one day and wanted to know what I thought of it. I said I thought it was kind of “hokey sounding”. He just laughed. It’s grown on me since and I like it now. I wonder why they never picked out a similar name for the 3 liter?


Having determined the basic parameters, 60 degree V6, with a bore of 3 1/8 in., stroke of 2.650 in., and cyl. center distance of 4 3/8 in., the other big decision was just how to form the transfer passages I had designed into a die - cast block. It was not possible to form them using the usual metal slides because half of them are buried deep in the middle of the casting. OMC had been successfully casting them in their 3 cylinder looper for several years using cast iron blister liners as inserts in the die and that looked like the only way to do it at that time. Salt cores were very experimental then and “lost foam” was still a long way off. Blister liners form the transfer passages and exhaust port as part of the cast iron liner. The exhaust port is machined open by a milling cutter after casting. The blisters have to be made heavy enough to withstand the very high (5000 psi) casting pressure. You might say why not just use sand cores like is done with most of the automotive blocks today. Sand cores would not stand up to the high velocity metal being rammed into the die, and any sand residue left in the die would rapidly wear out the metal slides which must fit closely together. As far as I know, sand cores are only used in gravity fed or low pressure filled molds.


I was concerned that we might have an infringement problem if we used blister liners so I called in our patent attorney and explained my concern to him. He assured me there would be no problem. I assumed by that that if any patents existed by OMC or others, they had expired. So, blister liners it was.

[1FASTLASER]

I've said once but I'll say it again. This is the most epic thread I have ever had the pleasure of reading. Glad to see you back rckid

[Hoss Marine Propellers]

I've said once but I'll say it again. This is the most epic thread I have ever had the pleasure of reading. Glad to see you back rckid

Yeah ...... What he said!!!! Thanks Again. :iagree:

[Onetime]

Glad to have you back posting this great history!! Looking forward to more!

[rckid74]

Let’s talk now a little about the piston and cylinder head design. I had made up my mind back at the beginning that I would much prefer a flat top piston as opposed to a crowned one or some other shape. Two main reasons - first, the flat top has the smallest surface area to absorb heat and should run the coolest, very important in any 2-stroke engine. Secondly, compression ratios could readily be changed just by flat milling the head mounting surface. Other advantages were shorter overall height to the top of the plug, ease of machining the piston top, and tighter control of the squish gap. In doing the flow tests on my “Jante Fixture”, I had found that it was easier to get good flow patterns with a domed top piston but with somewhat more effort I could get just as good patterns with a flat top. The only disadvantage I can think of would be that there would be a little greater heat concentration at the timing edge in the area of the exhaust port. We never experimented with domed pistons.
The prototype pistons were made of 356-T6 sand cast aluminum alloy which has about 7-10% silicon content. These worked well. I don’t remember having any problems with them but when we went to the forged production pistons, which had about the same silicon content, we had terrible problems with wrist pin pound-out. Actually, it was a combination of wear and stretching of the hole in the piston. I don’t remember the alloy number of the forged pistons but it was the same as we had been using for years in the in-line 6. At that time I didn’t know of any better alloy to use. We struggled to get the life up on those pistons and we did improve it but it wasn’t until we discovered high silicon (19-23%) hyper-eutectic cast pistons later on that the wrist pin problem went away. These were made by Art Metals, a company in Japan. I believe it was Ray Reid who first tried them in the V6.
I had also decided early on that I wanted to use a hemi head combustion chamber. This stemmed in part at least from my experience driving my fathers 1952 Chrysler New Yorker with it’s hemi-head V8. It was a real torquer. I figured that if they went to all that trouble to put those valves in at odd-ball angles it must have some real advantage over the other chambers. Obvious advantages are short flame travel distance from the plug to the end gasses, and low surface area to volume ratio. The dome was centered and positioned in the head so as to give 55% squish area which was considered optimum. I don’t remember the compression ratio we settled on for the first production.

[Capt.Insane-o]

I never understood why they went away from the (your) nice smooth hemi style chamber to the sharp edged top hat style.Maybe it came with the lost foam and machining costs.

[Dave S]

Better spark plug intrusion. While I was working at a HP shop in NY .....Chip Watkins and Joey Impressas were trying to re-use small chamber heads that had been cut too tight. I said why not Donut chamber.....Put the plug rite in the center of the gas charge. I think Chip found a shop that could cut the heads donut style chamber. The newer 90hp motors have that chamber.... It is good to see an Idea come to use. I only worked there.....as meck. Top hat spark closer to charge. Hemi spark too close the cool metal.

[rckid74]

Another important aspect of the engine was the water cooling system. I had heard of a previous attempt some years before at a V type engine at Mercury which had failed because of cooling problems. It was logical to study OMC’s cooling system and then only make those changes which made sense or were required due to our new configuration. After all, they had been making V engines successfully for many years.
The system is what I would call a double pass in that the water makes two loops thru the block, heads, and covers, entering the bottom of the engine, flowing to the top, back to the bottom, then back to the top, and finally to the bottom and out. This tends to equalize cylinder temps. Initially the cold water from the pump flows thru a passage cast from bottom to top between the banks and along the lower side of the exhaust ports which helps cool the bottom of the exhaust ports. The other side of this passage contacts the crankcase area and this coldest water helps keep the inlet cool for a more dense charge. Then at the top of the block the water crosses over into the exhaust cover where it is preheated some more before passing thru six sets of holes positioned such that it is directed down onto the top of the exhaust ports, the hottest area in the cylinders. Deflectors between the cylinders then cause the water to circulate around the cylinders and up to the top again where it crosses over into the heads and then down and out thru the poppet valve at the bottom of the block.
A thermostat at the top of each head controls water temp at idle. In an attempt at a little cost savings I had made the stupid mistake of putting a single thermostat down at the bottom of the block along side the poppet valve and using the same cover. That was neat and cheap but it didn’t work very well. Joe Harrelson quickly solved the problem and put in the two thermostats, one at the top of each head. However, before he found that solution, the block die had already been made with the opening for the single thermostat next to the poppet valve so that was just not used but it stayed in the block die for years after and I’m sure many people wondered what the heck that was for. I assume it has been deleted by now.
The output flow from the thermostats is carried to the bottom of the block thru hoses and looks like an after thought, which it was. I’ve always hated the look of those hoses hanging out there like that. Had I made the correct decision during the original design, I’d have cast drain passages in the head covers. Ah, hind sight.

[194268]

A few months after I was hired by Doc. Morgan, I think it was Nov. or Dec of '73 I saw prints of the V-6. How close would they have been to production ???

[Dave Strong]

Another important aspect of the engine was the water cooling system. I had heard of a previous attempt some years before at a V type engine at Mercury which had failed because of cooling problems. It was logical to study OMC’s cooling system and then only make those changes which made sense or were required due to our new configuration. After all, they had been making V engines successfully for many years.
The system is what I would call a double pass in that the water makes two loops thru the block, heads, and covers, entering the bottom of the engine, flowing to the top, back to the bottom, then back to the top, and finally to the bottom and out. This tends to equalize cylinder temps. Initially the cold water from the pump flows thru a passage cast from bottom to top between the banks and along the lower side of the exhaust ports which helps cool the bottom of the exhaust ports. The other side of this passage contacts the crankcase area and this coldest water helps keep the inlet cool for a more dense charge. Then at the top of the block the water crosses over into the exhaust cover where it is preheated some more before passing thru six sets of holes positioned such that it is directed down onto the top of the exhaust ports, the hottest area in the cylinders. Deflectors between the cylinders then cause the water to circulate around the cylinders and up to the top again where it crosses over into the heads and then down and out thru the poppet valve at the bottom of the block.
A thermostat at the top of each head controls water temp at idle. In an attempt at a little cost savings I had made the stupid mistake of putting a single thermostat down at the bottom of the block along side the poppet valve and using the same cover. That was neat and cheap but it didn’t work very well. Joe Harrelson quickly solved the problem and put in the two thermostats, one at the top of each head. However, before he found that solution, the block die had already been made with the opening for the single thermostat next to the poppet valve so that was just not used but it stayed in the block die for years after and I’m sure many people wondered what the heck that was for. I assume it has been deleted by now.
The output flow from the thermostats is carried to the bottom of the block thru hoses and looks like an after thought, which it was. I’ve always hated the look of those hoses hanging out there like that. Had I made the correct decision during the original design, I’d have cast drain passages in the head covers. Ah, hind sight.

This great information!! Keep it coming.

Dave

[rckid74]

The “Black Max” intake system ended up being very similar to the then OMC V4 with the six reed blocks set in vertically and three dual throat carbs. However, we did consider using horizontal, straight in reed blocks using dual throat carbs and a special manifold which would deflect the flow from one throat up to the higher cyl. and the other down to the adjacent lower one. See the patent # CA 1144078 A1 by Kieth Gagnier and David Kusche. This manifold presented problems with fuel puddling at low speeds and did increase the fore/aft length of the overall package by an inch or so. For these reasons we decided to stay with the proven design ala OMC.
I don’t now recall what design OMC used for the carb float bowl but I wanted to use a separate float for each cylinder, I.E. six floats. With each nozzle centered in a float the engine would receive a consistent fuel/air ratio even in hard turns. And that is what we used for all the prototype engines and they worked fine. However, before we went into production, I was told by upper management to save some money by going to a single float for each carb, which I did - against my will. Sure enough, after production started we started getting reports of engines running poorly in hard turns so we had to change back to the dual float carbs.
The inlet air box was designed by Dick Lanpheer and it did a very effective job of quieting the induction noise. I can verify that because I was doing some work with the engine on a boat one day and for some reason left the air box cover off and the cowl off. When I started up the engine, I swear, it sounded just like a stacker inline six. It was really loud. There’s a lot of noise coming out of those inlets. It was fun driving it around like that. That boat felt like a tunnel hull.

[Onetime]

Great stuff!

[Scream And Fly]

What an incredible thread. Thank you to everybody that is making this thread incredible!

Greg

[rckid74]

I knew the exhaust system on this narrow angle 60° V6 would be a challenge. There’s not much room between the banks to fit in two separate ducts of adequate area - one for each 3 cylinder bank. It was immediately apparent that I’d have to cast the exhaust chest open as one cavity and then use an inserted divider plate to define the two ducts because the large milling cutter required to cut open the exhaust blisters on the liners had to come in at an angle which would have cut thru any cast-in dividing wall. This also allowed me to gain a little additional area for the exhaust since the divider plate could be cast thinner than a cast-in water cooled wall. Getting a good seal between this divider plate and the block cavity was achieved by using a tongue and groove shape plus a compressed strip of high temp silicone “O”-ring material in the bottom groove. The ends of the dividing wall are only partially sealed by the tongue. Sealing these ends with silicone sealer will show a slight power gain but this was impractical for production.
Cocking the liners at a 30° angle in order to nestle the transfer passages presented a problem with the exhaust snouts. If a single liner was used for both banks, the snouts for one bank would be pointing down - more or less - and the other bank would be pointing up. This would just not do. So I had to bite the bullet and opt for two different liners, one for the starboard side and one for the port. This also meant we’d need starboard and port pistons - undesirable because of the possibility of mix-ups and the obvious cost increase - but necessary.
In the end we had a nice tight exhaust system with very short distances between tuning ports which helped to peak out the torque curve.

[Merc Fanatic]

This is one of if not the best thread I've read on S&F... thank you and please keep it going!!!

[Murph]

:iagree:, the Best.

[Greg G]

The details you are giving are true history. Thanks for that!

[rckid74]

The V6 ignition system was initially intended to be the same as the inline 6, that is, with a belt driven distributor, capacitor discharge type, single large ignition coil, single switchbox, using as much hardware from the inline engine as possible. And if you look at the pictures of “Old Blue” back on page 6 you’ll see how that looked. You can tell also that we had not taken the time to put on accessory mounting bosses. The anchor bracket is a cobbled up inline 6 unit and the throttle and spark stops were not cast on but were instead a bent steel bracket. By the way, we didn’t make all that many sand cast engines. The first batch was just 3 units and they acted as the proof of concept engines. Then I believe there were two more batches of about 8-10 each. These served as the dock and boat endurance engines.
My intention was to run the spark leads down from the distributor, around the bottom of the port head, over to the exhaust cover, and then up along side each head and to the plugs. I didn’t want to drape them across the sides of the heads because of the additional width this would have added to the overall package, and I was fighting for the narrowest engine possible. This also left the back of the engine wide open and so I cast a MERCURY name with several vertical ribs onto the exhaust cover mimicking, somewhat, the Ferrari logo I had seen and admired on some of their engines. The intention was to paint the cover black and then sand the paint off the protruding name and ribs to make them stand out. Perhaps painting them white or silver might have been better. If JFL would take a picture of the back of “Old Blue” you can see what that looked like.
But alas, all that went bye the wayside when, about half way thru the program, I was informed that the distributor was to be replaced by a six coil, distributor-less system which the electrical boys had been working on for some time. That was a major blow for me and the schedule. All the drawings were done, the testing was well on its way, and now we had to reverse course. I was not a happy camper. I would estimate that the change set us back about a half year. But it had to be done so I, grudgingly, started in on it. The only logical place to mount the six coils was on the exhaust cover so there went my MERCURY logo. In the end I’m sure it was for the better but dam I hated all the extra work that it created.
I hope that if they ever go to a coil on plug setup, they put my MERCURY logo back on the cover.

[Dave Strong]

The V6 ignition system was initially intended to be the same as the inline 6, that is, with a belt driven distributor, capacitor discharge type, single large ignition coil, single switchbox, using as much hardware from the inline engine as possible. And if you look at the pictures of “Old Blue” back on page 6 you’ll see how that looked. You can tell also that we had not taken the time to put on accessory mounting bosses. The anchor bracket is a cobbled up inline 6 unit and the throttle and spark stops were not cast on but were instead a bent steel bracket. By the way, we didn’t make all that many sand cast engines. The first batch was just 3 units and they acted as the proof of concept engines. Then I believe there were two more batches of about 8-10 each. These served as the dock and boat endurance engines.
My intention was to run the spark leads down from the distributor, around the bottom of the port head, over to the exhaust cover, and then up along side each head and to the plugs. I didn’t want to drape them across the sides of the heads because of the additional width this would have added to the overall package, and I was fighting for the narrowest engine possible. This also left the back of the engine wide open and so I cast a MERCURY name with several vertical ribs onto the exhaust cover mimicking, somewhat, the Ferrari logo I had seen and admired on some of their engines. The intention was to paint the cover black and then sand the paint off the protruding name and ribs to make them stand out. Perhaps painting them white or silver might have been better. If JFL would take a picture of the back of “Old Blue” you can see what that looked like.
But alas, all that went bye the wayside when, about half way thru the program, I was informed that the distributor was to be replaced by a six coil, distributor-less system which the electrical boys had been working on for some time. That was a major blow for me and the schedule. All the drawings were done, the testing was well on its way, and now we had to reverse course. I was not a happy camper. I would estimate that the change set us back about a half year. But it had to be done so I, grudgingly, started in on it. The only logical place to mount the six coils was on the exhaust cover so there went my MERCURY logo. In the end I’m sure it was for the better but dam I hated all the extra work that it created.


Merry Christmas and thank you so much for your input!!!


Dave

[milkdud]

What a great read. Thanks for sharing.
Conrad

[rckid74]

A few words need to be said about the head hold-down screws and how they arrived at their present position. Many of you probably don’t even know that they, for the first couple of years in production, were in bosses attached to the cylinder wall instead of in bosses in the outer water jacket as they are now.
In my years at Mercury before I was given the V6 assignment, I had done quite a bit of work experimenting with piston deflector and combustion chamber shapes. To do this we used twin cylinder engines with removable heads and we had a lot of trouble blowing head gaskets. I found that the best solution was to get the head screws in close to the cylinder wall and to keep the head as stiff as possible. I was aware that screws in bosses attached to the cylinder could cause distortion of the cylinder and consequent piston scuffing and ring problems. My solution was to bury the threads down as deep below the deck surface as possible. This surrounds the threads with much more material to resist distortion than would be the case if the threads started right at the top of the cylinder. This worked well in those experimental engines but, of course, there was never a lot of endurance time put on them. That was the approach I decided to use in the V6 and we had no trouble in all the endurance testing done before production. However after production startup we started getting reports of occasional scuffing problems. Our original fix was to bore and hone the cylinders using a dummy head torqued to the block. This worked well but was costly and time consuming so the bolts were then moved off the cylinder wall to their present position. Live and learn.

[3030]

A few words need to be said about the head hold-down screws and how they arrived at their present position. Many of you probably don’t even know that they, for the first couple of years in production, were in bosses attached to the cylinder wall instead of in bosses in the outer water jacket as they are now.
In my years at Mercury before I was given the V6 assignment, I had done quite a bit of work experimenting with piston deflector and combustion chamber shapes. To do this we used twin cylinder engines with removable heads and we had a lot of trouble blowing head gaskets. I found that the best solution was to get the head screws in close to the cylinder wall and to keep the head as stiff as possible. I was aware that screws in bosses attached to the cylinder could cause distortion of the cylinder and consequent piston scuffing and ring problems. My solution was to bury the threads down as deep below the deck surface as possible. This surrounds the threads with much more material to resist distortion than would be the case if the threads started right at the top of the cylinder. This worked well in those experimental engines but, of course, there was never a lot of endurance time put on them. That was the approach I decided to use in the V6 and we had no trouble in all the endurance testing done before production. However after production startup we started getting reports of occasional scuffing problems. Our original fix was to bore and hone the cylinders using a dummy head torqued to the block. This worked well but was costly and time consuming so the bolts were then moved off the cylinder wall to their present position. Live and learn.

Thank you. Very interesting to hear the engineering perspective on the position of the head studs. I found head studs and proper torque also solves the issue in endurance applications. Here is my latest rebuild of a '76 1750 with ARP studs and later style water jackets on the heads. I assume you went to the deep water jackets for increased cooling and inside of the heads changed as well to allow for better water flow?

[Dave Strong]

Not sure why but have found studs work great on 2 and 2.4L but the few times tried them on 2.5L they seemed to not hold?? Makes no sense but that's what happened, anyone else see this???

Dave

[Dave Strong]

and PS not to take away anything from this thread, its all about history. So anything Tech should be on a different thread. Sorry my bad for even going there.

Dave

[FUJIMO]

Jerry, all the first generation 1750XS blocks that were raced(and beyond) utilized head studs with no problems. I know you didn't get involved with the first race powerheads much, so thought you would appreciate this. Thanks again, very much, for all your Merc history.

[rckid74]

The “Black Max” cowl originally was the, so-called, clam-shell type. Kind of like a clam laid over on its’ side. That is, hinged in the back with a vertical split between the two halves and a latch in front. This cowl type had been pioneered several years earlier on the M650 three cylinder and was considered to be successful. I liked it for two main reasons. First, it allowed the cowl to hug the engine closer which gave a slightly narrower overall package, and second, when removed, gave excellent access to all the engine components right down to the driveshaft housing. It was also relatively inexpensive to make. After a time in the field though, a couple of complaints cropped up. People were having trouble getting the cowl back on the engine especially if out on the water in a pitching boat. Getting the hinge pins lined up was difficult if you weren’t familiar with the setup. Also, the seal strip around the bottom would sometimes not properly engage the groove in the cowl halves resulting in leakage. And so, after several years of production, we changed to the standard top cowl, bottom pan design. A change for the better, I guess.

[Slimm]

The “Black Max” cowl originally was the, so-called, clam-shell type. Kind of like a clam laid over on its’ side. That is, hinged in the back with a vertical split between the two halves and a latch in front. This cowl type had been pioneered several years earlier on the M650 three cylinder and was considered to be successful. I liked it for two main reasons. First, it allowed the cowl to hug the engine closer which gave a slightly narrower overall package, and second, when removed, gave excellent access to all the engine components right down to the driveshaft housing. It was also relatively inexpensive to make. After a time in the field though, a couple of complaints cropped up. People were having trouble getting the cowl back on the engine especially if out on the water in a pitching boat. Getting the hinge pins lined up was difficult if you weren’t familiar with the setup. Also, the seal strip around the bottom would sometimes not properly engage the groove in the cowl halves resulting in leakage. And so, after several years of production, we changed to the standard top cowl, bottom pan design. A change for the better, I guess.



rckid74, I want to thank you for taking the time to give us all the technical information as well as the behind the scenes stories and general historical facts that so many of us have wondered about. I have thoroughly enjoyed reading your post and especially the engine technical data, some of which I understood and some I didn't...and still some I didn't understand until your posts at which time the little light in my head went off and clarity occurred.


Slimm

[wogi]

rckid74, I would like to thank you for all this neat info and the time you are taking to put it down into words for all of us to enjoy!!!!
I feel that you should be proud of the fact that your hard work so many years ago as became the mainstay and the benchmark of performance boating as we know it today!
Did you ever have any idea that you and the others you work with were engineering the marine equivalent of the small block chevy?
Sorry to take away from this tread, but I just wanted to express my graditude for what you done in the past and what you are doing here!!!!!!!!
THANKS AGAIN:cheers:

[Onetime]

Everybody following this thread feels the same way about the marvelous piece of engineering you did creating the Mercury V-6.
Jerry, let us know when you would like some questions. I'm sure there are lots out there just holding back. I know I am! Only problem will be there will be lots and lots of questions.

[Dave Strong]

Everybody following this thread feels the same way about the marvelous piece of engineering you did creating the Mercury V-6.
Jerry, let us know when you would like some questions. I'm sure there are lots out there just holding back. I know I am! Only problem will be there will be lots and lots of questions.

Keep it coming!!!

Dave

[Da Bull]

I think the clam shell cowl was the best production cowl made for Mercury engines. It was light, Easily removed and offered easy access to the intire engine components. Merc threw us a curve with the horizontal front latch as it would blow off when the front plate was not in place. Easy fix was drill a 1/4" hole through the two locking jaws and install a tie strap to hold them together.

I love this thread and cannot get enough of it.

DB

[2us70]

The top cowl on my 225 Optimax weighs a ton. I wonder why it was made so heavy.
I think the clam shell cowl was the best production cowl made for Mercury engines. It was light, Easily removed and offered easy access to the intire engine components. Merc threw us a curve with the horizontal front latch as it would blow off when the front plate was not in place. Easy fix was drill a 1/4" hole through the two locking jaws and install a tie strap to hold them together.

I love this thread and cannot get enough of it.

DB

[powerabout]

How about the rectangular blind flanges on the block side of each cylinder on the early blocks, whats the story behind that?

[rckid74]

How about the rectangular blind flanges on the block side of each cylinder on the early blocks, whats the story behind that?
Those were added by Ron Anderson when he first started developing the T3. He was planning to add additional reed blocks there but I don't think he ever did as the toliet bowl fuel injection was a better solution. The idea was to suck only air thru those reed blocks and then run the front carbs extra rich to give the correct F/A ratio.

[rckid74]

Everybody following this thread feels the same way about the marvelous piece of engineering you did creating the Mercury V-6.
Jerry, let us know when you would like some questions. I'm sure there are lots out there just holding back. I know I am! Only problem will be there will be lots and lots of questions.
Thanks for all the encouragement. I'm planning to have a Q&A session later. Still have a way to go with the main story though.

[powerabout]

Many thanks rckid74, I see a book coming???

[Dave S]

Was that the Ron Anderson that ran A hydro in conn in the 70s?

[rckid74]

Was that the Ron Anderson that ran A hydro in conn in the 70s?
Could be! He was from the Seattle area but he raced hydros all over the country.

[John Schubert]

That's who it is/was. Still building race engines for the F1 tour teams primarily the Qtar team

[Dave Strong]

Who created the horn?

Dave

[RBT]

Brendan power is qatar
ron builds for Abu Dhabi

[rckid74]

Who created the horn?

Dave

Probably the dinosaurs. Just kidding. What horn are you talking about?

[Dave Strong]

The horn style EFI like Bridgeport, 260 and 280's.

Dave

[powerabout]

I guess he means the EFI offshore throttle body/horn?
thats just a neat cost efficient way to do that I would say

[JFL]

It has that exhaust cover on it, send me your e mail and I will send it to you

[powerabout]

Jfl
Was there ever a plan to do a v4 to replace the inline 6
That would have been a good product i feel

[rckid74]

The V6 ignition system was initially intended to be the same as the inline 6, that is, with a belt driven distributor, capacitor discharge type, single large ignition coil, single switchbox, using as much hardware from the inline engine as possible. And if you look at the pictures of “Old Blue” back on page 6 you’ll see how that looked. You can tell also that we had not taken the time to put on accessory mounting bosses. The anchor bracket is a cobbled up inline 6 unit and the throttle and spark stops were not cast on but were instead a bent steel bracket. By the way, we didn’t make all that many sand cast engines. The first batch was just 3 units and they acted as the proof of concept engines. Then I believe there were two more batches of about 8-10 each. These served as the dock and boat endurance engines.
My intention was to run the spark leads down from the distributor, around the bottom of the port head, over to the exhaust cover, and then up along side each head and to the plugs. I didn’t want to drape them across the sides of the heads because of the additional width this would have added to the overall package, and I was fighting for the narrowest engine possible. This also left the back of the engine wide open and so I cast a MERCURY name with several vertical ribs onto the exhaust cover mimicking, somewhat, the Ferrari logo I had seen and admired on some of their engines. The intention was to paint the cover black and then sand the paint off the protruding name and ribs to make them stand out. Perhaps painting them white or silver might have been better. If JFL would take a picture of the back of “Old Blue” you can see what that looked like.
But alas, all that went bye the wayside when, about half way thru the program, I was informed that the distributor was to be replaced by a six coil, distributor-less system which the electrical boys had been working on for some time. That was a major blow for me and the schedule. All the drawings were done, the testing was well on its way, and now we had to reverse course. I was not a happy camper. I would estimate that the change set us back about a half year. But it had to be done so I, grudgingly, started in on it. The only logical place to mount the six coils was on the exhaust cover so there went my MERCURY logo. In the end I’m sure it was for the better but dam I hated all the extra work that it created.
JFL sent me this picture of the exhaust cover on "OLD BLUE".292766

[Capt.Insane-o]

Nice! Some one needs to go get that poor thing right side up and on a stand. :(

[rckid74]

Jfl
Was there ever a plan to do a v4 to replace the inline 6
That would have been a good product i feel
We did look at a V4 version of the V6 as a follow-on project to Black Max. It was a 60° block also and used the same guts, except for the crank, as Black Max. . The intention was to machine it on the V6 block line. Several different firing orders were tried by arranging the crank pins in different ways but none panned out to give what we were looking for. One I tried fired the first two cylinders 120° apart and then fired the last two cylinders together 120° later. So this fired like a three cylinder and was intended to benefit from exhaust pulse tuning and it was the most powerful one we tried but it had a strange sound at low speeds and the balance was not particularly good either. This engine was to have filled in the 110 to 135 HP range. In the end the ‘powers-that-be’ decided to go with an in-line 4cyl and an in-line 3cyl using all common parts. That way we could cover the entire midrange from 75 to 135 HP with new loop engines.

[Merc Fanatic]

We did look at a V4 version of the V6 as a follow-on project to Black Max. It was a 60° block also and used the same guts, except for the crank, as Black Max. . The intention was to machine it on the V6 block line. Several different firing orders were tried by arranging the crank pins in different ways but none panned out to give what we were looking for. One I tried fired the first two cylinders 120° apart and then fired the last two cylinders together 120° later. So this fired like a three cylinder and was intended to benefit from exhaust pulse tuning and it was the most powerful one we tried but it had a strange sound at low speeds and the balance was not particularly good either. This engine was to have filled in the 110 to 135 HP range. In the end the ‘powers-that-be’ decided to go with an in-line 4cyl and an in-line 3cyl using all common parts. That way we could cover the entire midrange from 75 to 135 HP with new loop engines.

I would like to say thanks again for an incredible thread. Best read on S&F ever IMO. Just curious are there any photos of the V4 engine anywhere. I think it would be cool to see if there were.

[rckid74]

I would like to say thanks again for an incredible thread. Best read on S&F ever IMO. Just curious are there any photos of the V4 engine anywhere. I think it would be cool to see if there were.
Not that I'm aware of.

[powerabout]

They should have looked at a 90 v4 with same parts
Yam sold lots of looper v4's
Then a 3 cyl looper to fill in the under 100hp
Would have been a powerful lineup

[JFL]

The V4 was so secret not a lot of people at Mercury saw it, much less get a picture of it. I only saw it on a boat a couple of times at Plt 33.

[Steve Pope]

Great thread. Nice to be able to see how a marine icon was born. One question. That resonance in the engine around 3200rpm, was it ever a concern? Thanks, Steve

[powerabout]

Great thread. Nice to be able to see how a marine icon was born. One question. That resonance in the engine around 3200rpm, was it ever a concern? Thanks, Steve
I dont think it happens on the 2 ltr

[JFL]

I remember testing at that RPM for a very long time, never saw any damage other than my ears

[rckid74]

Great thread. Nice to be able to see how a marine icon was born. One question. That resonance in the engine around 3200rpm, was it ever a concern? Thanks, Steve
3200rpm is a speed that doesn't see much time at high throttle. Most people pass thru it and don't feel or hear anything. I'm not aware of it ever being a problem. We never broke any cranks that I know of.

[JFL]

The serial number of old blue is 6720824 I think it was a date code, if it is then it was built in 1967

[rckid74]

A few words about the accessories arrangement under the cowl and the undercarriage and then on to the development and production startup, followed by the 2.4L, the V4, and the X12 projects. Maybe those last two belong in a different thread but they are directly related to the 2L V6 so I’ll keep them here.


I’m sure most of you remember how the accessories were arranged on the inline 6 with the wiring harness outside the cowl plugging into a receptacle mounted in the bottom pan on the st’bd side and the fuel connector also on the st’bd side and the control cables on the port side. Then , inside the cowl, the switchbox and rectifier were mounted on the front support plate, while the fuel pump was on the st’bd side. Thus there were electrical wires and fuel lines in close proximity which I didn’t think was a good idea. I wanted to separate the two putting all the electrical stuff on the st’bd side and all the fuel stuff on the port side. Now I’m talking strictly about the original V6 here. I realize that later with fuel injection and later still, direct injection, things got somewhat messier under the cowl.
The clamshell cowl would not allow an outside wiring harness plugin like the inline 6 so I moved the fuel connecter over to the port side where all the fuel stuff would be and brought the wiring harness thru the front on the st’bd side where it could flow smoothly into the electrical mounting plate and the fuel-in could flow smoothly into the fuel pump, filter and carbs on the port side. Now all the electrical components could be mounted on a diecast plate making a nice subassembly. This plate was then rubber mounted to the block to isolate everything from vibration. The starter was already on the st’bd side so was close to the start solenoid on the plate.
All in all, I was quite happy with the new layout and I don’t recall it having any problems.

[rckid74]

The serial number of old blue is 6720824 I think it was a date code, if it is then it was built in 1967
Apparently that serial number did not act as a date code because the V6 was not even thought about in 1967.

[T2x]

The serial number of old blue is 6720824 I think it was a date code, if it is then it was built in 1967

Is it possible that the first 3 numbers "672" meant "6 cylinder 1972 ?

[rckid74]

Is it possible that the first 3 numbers "672" meant "6 cylinder 1972 ?
But even 1972 would not be correct because I'm quite certain it was built either in late '70 or early '71.

[HStream1]

Its a Julian date.

[rckid74]

Here are some pictures of "OLD BLUE" back when she was new.295622295622295622

[194268]

Sweet, where were the pictures taken, was it Fond Du Lac?

[FUJIMO]

Here are some pictures of "OLD BLUE" back when she was new.295622295622295622
Initial mounting/set-up. Thanks again Jerry. Wait till everyone hears the V-4 story...These were great times@Merc. :thumbsup:

[Capt.Insane-o]

:thumbsup::thumbsup:

[allstock]

Wow, best thread ever. I just read the whole thing, start to finish. Great job, thank you!!!

[Merc Fanatic]

I will say it again... The best read ever on S&F!! Thank you and keep it coming!!! :thumbsup::thumbsup::thumbsup:

[rckid74]

Sweet, where were the pictures taken, was it Fond Du Lac?
These pics were taken at plt. 6 in Oshkosh. Sorry about the duplication. I’m not very computer savvy so probably hit some wrong buttons. I had wanted to post these back when I was talking about Old Blue but couldn’t find them. A couple days ago I found them while rummaging thru some drawers upstairs.
Now that I look at them closer, I see that only the first picture is of Old Blue. The others showing an engine on the propshaft dyno are of one of her sisters. The block is not dark blue.
Here are a few more of the same engine and showing more of the dyno hookup.
295709295778

[rckid74]

There was nothing very unusual about the undercarriage. Between the powerhead and driveshaft housing were two adapter plates which trapped the upper mounts and also received the water from the pump and distributed it to the main inlet and some drain holes. A little was also sprayed into the exhaust to help boost the bottom end power. The exhaust extenders were bolted to the lower plate and dumped the exhaust into the exhaust collector tube which also formed the wall of water between it and the DSH.
As I recall, the gearcase was beefed up a bit but otherwise was typical Mercury.
The clamp bracket assembly was all new but at that time still used the hydraulic trim system with the pump inside the boat. Normally the hydraulic lines went from the pump, over the transom, and down to the trim cylinders. And yes, it was me, who had the bright idea to simplify that by drilling through the lower mounting bolts and routing the hydraulic oil from the pump, thru the bolts, and then connecting the outer end to the cylinders. Very neat and tidy. Well I should have stuck to engine design and kept my nose out of an area I knew nothing about. I had never mounted an engine on a boat in my life and didn’t realize that these bolts get pounded into holes, that didn’t quite line up, with big hammers and that silicone sealers were pumped into the holes first. These things were not conducive to making a good connection. Needless to say, a redesign was hurriedly put in place.

[jjamieson7284]

Read all the pages and couldn't get enough very awsome

[powerabout]

I remember those bolts.
They should have been shipped with bronze nuts to prevent the SS ones from gauling/picking up ( even when lubed)

[Capt.Insane-o]

I have quite a few sets of those bolts, they were a great idea until the ham fisted bozos got a hold of them like said above.

[powerabout]

yep good idea just needed to be shipped with bronze nuts

[njj502]

I had never seen the thru bolt until about a year ago when Rock showed em to me. Great idea but the application was not quite ideal. Thanks again for these posts. I'm loving it.

[rckid74]

The first several sandcast engines were built using hardware that was very minimal in detail features. They’re only purpose in life - at least initially - was to show power level, fuel economy, vibration level, cooling characteristics, and basic durability. Once these were determined to be good, upper management gave the go-ahead to finish up the design and head for production. I’m guessing now, but I’d say this point was reached about 12 to 14 months into the program.
In order to get some boat performance data we had to adapt the new powerhead to the in-line 6 undercarriage. While not ideal, that was the best we could do short term. Boat and dock endurance proceeded. Additional sand cast units were built. Design of the production undercarriage, engine accessories, and cowl proceeded with all haste. Sand cast parts were made. Hand-layed-up fiberglass cowls were made. By early ‘72 we had a complete sandcast prototype unit. Testing proceeded, changes were made and retested time and time again. Later that year we felt ready to start production tooling.
Now production tooling rarely ever produces parts that perform just like your previous prototype parts. For one thing, vendors and our own production people are always asking for changes to facilitate their making of the parts. Making and testing these new parts with all these changes is what we spent most of our time doing for the next couple years. As an example, I recall that the production cylinder liners did not give as good flow patterns as what I had developed on the “Jante Fixture”. We made some changes and improved the patterns a little but they never were as good as the originals. This was just typical of the hundreds of new parts. This engine used almost no parts from any of the then in production engines. The spark plugs are the only part I can think of that weren’t new. So this was a major, major undertaking for Mercury.

[Mark75H]

At about this time Merc unveiled the last of the inline 6 race motors, the T2X which used the mid section that would be later used under the V-6 and had the not yet released V-6 base pattern with an adapter for the inline powerhead.

Would you say this was because V-6 development was behind or that the mid section with the V-6 pattern was just built in anticipation of the V-6 coming in the future?

[rckid74]

I'm not familiar with the T2X mid section. My guess is that it was a special sand cast unit used only for racing. The V6 engine was developed well ahead of its' mid section. As I indicate above, we had to make a special adaptor plate to mount it to the inline mid section just to get some boat testing done. The production V6 mid section came somewhat later.
At about this time Merc unveiled the last of the inline 6 race motors, the T2X which used the mid section that would be later used under the V-6 and had the not yet released V-6 base pattern with an adapter for the inline powerhead.

Would you say this was because V-6 development was behind or that the mid section with the V-6 pattern was just built in anticipation of the V-6 coming in the future?

[stace911]

Thanks Jerry for the great history lesson! I was just a small kid in the late 70's who spent summer days at Lake Sam Rayburn in east Texas and remember the infamous name "Black Max" on boats that had a sound like no other. My childhood dream was to someday own one. Just one year ago my dream came true!

Stace

[99fxst99]

I remember those drilled bolts well, especially crawling into the bilge of a bass boat to hook them up. Cross threaded a few of those!
How was it that the early engines had the oddball transom bolt pattern?
GREAT thread! Thanks for all this info!

[rckid74]

I’ve been pondering just how to approach this next entry, that is, the introduction by OMC of their 200 HP V6. A lot of this will just be my opinion as I don’t have a lot of facts about that. So, here goes.


We, Mercury, had made a 50 unit pre-production run of our V6 sometime in early 1975. However, problems developed which prevented us from making a mid-summer introduction. I forget just what those problems were, they may have been either engineering or manufacturing in nature, most likely a little of both. We spent the better part of that summer correcting those, aiming for a second run that Fall. It was during this time that OMC introduced their V6. I, for one, was devastated, deflated. I had no idea that was coming and I doubt anyone else at Mercury did either. True, I had seen evidence several years before which proved that OMC knew about our V6 and in fact had detail knowledge of it, but I had no idea they were proceeding with their own. Perhaps they were already working on it before they found out about ours but, in any case, that knowledge would have spurred them on to complete it before ours came out.


Here’s what I think actually happened. OMC finds out sometime in the early seventies about our 2 liter V6 and decide they have to do something. The easiest, quickest, and most effective counter play would be to just add 2 more cylinders to their V4. True, it would still be a cross flow engine but they would more than make up for that with displacement (150 ci. to 122 ci.). If they kept the same 90° bank angle they could machine it on the V4 line, and could use the same rod-piston assy. and all the inlet system from the V4 also. This was a very much easier thing to do than what Mercury was trying to accomplish. One problem they faced was just how to handle the crankshaft configuration. If they kept two rods on one pin like in the V4, the firing order would be uneven (90-30-90-30-90-30). If they made the firing order even, they would have to offset the pins which would require a thicker web between pins. Then that would require greater bank offset and that would screw up the machining line. They made the obvious decision to go with the uneven firing order. I don’t know of any problems they experienced due to that. It might have had a funny sound at idle but at higher speed would hardly be noticed. The cycle to cycle torque peaks would be somewhat higher but not nearly so bad as if 2 cylinders were firing at the same time.
They pulled it all off and came out ahead of us. It was a brilliant solution and I give them full credit for it. They accomplished what they set out to do. I don’t know just how many years that engine stayed in production, probably less than 10. So I guess we get to have the last laugh since “Black Max” is still in production 39 years later.
I think this might be a good time to take on questions about the 2 liter and then I'll talk a bit about the V4 and the X12.

[Rotary John]

I’ve been pondering just how to approach this next entry, that is, the introduction by OMC of their 200 HP V6. A lot of this will just be my opinion as I don’t have a lot of facts about that. So, here goes.


We, Mercury, had made a 50 unit pre-production run of our V6 sometime in early 1975. However, problems developed which prevented us from making a mid-summer introduction. I forget just what those problems were, they may have been either engineering or manufacturing in nature, most likely a little of both. We spent the better part of that summer correcting those, aiming for a second run that Fall. It was during this time that OMC introduced their V6. I, for one, was devastated, deflated. I had no idea that was coming and I doubt anyone else at Mercury did either. True, I had seen evidence several years before which proved that OMC knew about our V6 and in fact had detail knowledge of it, but I had no idea they were proceeding with their own. Perhaps they were already working on it before they found out about ours but, in any case, that knowledge would have spurred them on to complete it before ours came out.


Here’s what I think actually happened. OMC finds out sometime in the early seventies about our 2 liter V6 and decide they have to do something. The easiest, quickest, and most effective counter play would be to just add 2 more cylinders to their V4. True, it would still be a cross flow engine but they would more than make up for that with displacement (150 ci. to 122 ci.). If they kept the same 90° bank angle they could machine it on the V4 line, and could use the same rod-piston assy. and all the inlet system from the V4 also. This was a very much easier thing to do than what Mercury was trying to accomplish. One problem they faced was just how to handle the crankshaft configuration. If they kept two rods on one pin like in the V4, the firing order would be uneven (90-30-90-30-90-30). If they made the firing order even, they would have to offset the pins which would require a thicker web between pins. Then that would require greater bank offset and that would screw up the machining line. They made the obvious decision to go with the uneven firing order. I don’t know of any problems they experienced due to that. It might have had a funny sound at idle but at higher speed would hardly be noticed. The cycle to cycle torque peaks would be somewhat higher but not nearly so bad as if 2 cylinders were firing at the same time.
They pulled it all off and came out ahead of us. It was a brilliant solution and I give them full credit for it. They accomplished what they set out to do. I don’t know just how many years that engine stayed in production, probably less than 10. So I guess we get to have the last laugh since “Black Max” is still in production 39 years later.
I think this might be a good time to take on questions about the 2 liter and then I'll talk a bit about the V4 and the X12.
OMC was working on the cross V-6 long before in infamous blueprint issue. Most of your other assumption are fairly accurate, except different firing orders weren't considered. Time and cost to introduce dictated the current V-4 with 2 more cylinders. Strang went so far as to have 150HP decals made for it to confuse Merc about the real 200HP. If my memory is correct he even certified a 150 HP version with the Merc people in attendance. The 200HP certification came later.

[powerabout]

v6 crossflow seemed like a quick and dirty solution to me, although the crossflow makes a great workhorse and that was proven all over the world.
Not a perfect solution as a race engine though
Surprised me knowing that OMC had production and race loopers ( inlines) prior to the V6 ( which didnt make good work horses when worked hard)
I assume bass boats were the largest market then as they are now so clearly it was all the other fishing markets they had in mind?
I have seen that Rick McChesney has a patent on an etec crossflow, now that would be a perfect workhorse.

[FUJIMO]

I think this might be a good time to take on questions about the 2 liter...
Thanks for remembering(lol), and putting to print everything so far Jerry. Much appreciated.:thumbsup: Question. Were any of the first 1750's produced with a "square" crankshaft "female" hole end. These would have been assembled as a complete engine, with a square lower-unit(gearcase) driveshaft top, to fit up into the crank bottoms square reciever. This would have replaced the traditional male/female spline marriage. That you know of, that is?

[194268]

When I was at Marine Engineering (OMC) in the year of '76, they where comparing their 200 to the 1750. I was informed that the 200 was slightly better on the top end and as the load went up the 1750 proved to be increasingly better. I asked why and was informed that the Mercury prop's where better.