bp 1250

[baker]

i recently aquired a complete bp1250 stacker with speedmaster
type gearcase. i intend to restore this motor to like new
condition in the next year or so. does anyone have any
pictures or literature on this motor. i have been told it is a
67 to 69 model. i believe my buddy has the microfish
from mercury still in his possesion. i am going to take pictures
of it now and as i go along. i dont have a digital camera to
post with but plan to get one. any one with info or history
please post, i would like to hear.

thanks
david baker

[Mark75H]

David the years are 68 & 69 ~ maybe 1970.

The 68's are different from the later ones. The 68 mid section has concealed transmission section mounting studs and nuts, the later type has scalloped in sections on the side of the mid to access the nuts from the outside. Very easy to tell them apart.

We have a lot of info on them here on Screamandfly, but your powerhead photos would be of great interest to us here, especially if yours is an early motor.

1969's were refered to as "Super BP's" and should have "1250" in white letters on the side near the top and a red racing stripe on the top from front to back.

Here is one thread from our history:
BP transmission (http://forums.screamandfly.com/forums/showthread.php?s=&threadid=24648&highlight=1250+bp)

an image from another thread (1969 version)
http://forums.screamandfly.com/forums/attachment.php?s=&postid=160491

If your motor is newer it may have an adapter and a regular Super Speedmaster

Super Speedmaster thread (http://forums.screamandfly.com/forums/showthread.php?s=&threadid=24317&highlight=super+speedmaster)

Again, these are 1969's:

[Mark75H]

`

[baker]

sam
thanks for the info. the more i learn about these old mercs,
the more i want to know. my motor has the red stripe cowling
with merc bp1250 on the back.it has the side latch for the
three pipes to exit. the lower unit appears to be the same
as the picture above. it even haswhat appears to be the
same stainless prop on it still. the power head is painted a
silver color i believe, and still turns over and has compression.
it has what appears to be a solenoid hooked to three tubes
that connect into the elbows of the stacks. some type of
water injection for the stacks. the lower unit turns with the
powerhead so at it is not locked up. the owner told me it was
one of a pair that were on a boat that basically rotted away,
and was running when it came off. the top cowl has merc 1250
on the side. i dont have the face place for the front, but the
wrap around had two holes in the front of it. the cowl wraps
around and latches on the side where the pipes exit.

i also have a 16' speedcraft (allison pop) that i have a
twister 11 midsection (the two hole exhaust) and cowling
(blue stripe) on with a stock 80 model inline three carb.
the looks i get at the river with that thing are neat.
i would love someday to get a complete twister powerhead.
i hope to eventually put the stacker on it and show it
at local shows (and maybe make a pass or two in it.)

i ll try to get some pictures posted in the next few weeks
your info is very helpful.

thanks
david baker

[Mark75H]

That much identifies your motor as a 1969. I think the front cover is the same as all other 1969 125hp Mercs.

You are correct, the solenoid and lines are water injection. It increases mid range power. Your motor may have very high exhaust porting for increased high rpm power. I have heard that some were ported so high that they could not push a boat over plane without using the water injection to bring the pipe's tuned length into play at lower rpm.

I believe your block may be much the same as a 135hp Merc.

Merc claimed the regular tuned pipe 1250 Super BP made 155 hp. Yours may make a little more.

I hope you meant putting the whole stacker motor on the boat because I think you will find that the bottoms of the mid sections have the same bolt patterns, but that the top of the BP mid and top of the Twister II mid probably have slightly different bolt patterns on the exhaust side and won't let you swap the powerheads.

If your T2 mid has the exact same bolt pattern as your BP and the T2 has the big bosses for the steering bar mount we would be very interested in seeing pictures of it when you get a chance.

Does your motor have a gearshift lever?

[baker]

sam

yes i intend to put the whole thing on at some point., when
i get through running the 3 carb inline.
neither the bp or the twister had a shifter. i made a shifter
for the twister by bolting the flange off a stock inline adapter
plate to the front two bolts of the powerhead. it has the adapter
plate on the mid to accept a stock gearcase. i haven't checked
real close, but the bp does not seem to have any type shift
mechanism on it. i intend to leave it as original as i can
possibly make it. are there any books on the old mercs
that i can get to have more info? in the next few weeks
i will try to get some pictures posted

thanks
david baker

[Raceman]

David, I've got at least one of everything Merc made in the old 6 cyl race motors from the BP's through all the Twisters. If you need specific photos of any particular area to duplicate a part I'll be glad to shoot em and send em. Your BP would've had a shift mechanism when new.

As far as the stacks, they're real neat looking but make the boats un-useable most anywhere. They're roughly as loud (maybe louder) than a top fuel car. They're also bottom end killers and probably in themselves account for the loss Sam was speaking of.

Does your cowl have a red stripe down the top of the top cowl and also down the front of the lower pan? Another way to determine the difference between the BP and Super BP is the covers over the tranfer ports on the starboard side of the engine. The std BP had the 6 individual rectangular covers, one on each cyl. The Super BP had the 3 covers with fins in em, with 2 cyls sharing 1 cover. I believe there's another unique feature to the Super BP block: I believe that they all had a steel, bolt on starter mount (old style), in conjunction with the 3 covers above (new style). I believe that all the production 1150/1350 blocks from 70 & 71 used the cast in the block starter mounts. If these unique characteristics ever overlapped into early production engines I've never seen an example of it. It's pretty clear that the 69 Super BP was a prototype design for the 70/71 production 1150/1350, which were the exact same powerheads in these two years except for reed stops and carb diffusers which were used to choke the 1350 down for the 1150 rating.

It's important to note that the std BP's were the last of the old crossflow engines and the Super BP's were the first of the direct charge engines.

[baker]

raceman,
this engine has the three covers on the intake side, not the
six separate covers. it has a red stripe on the top cowl with'
white pinstripe on both sides of the red. i dont have the
bottom cowl or face plate. i guess that makes it a super bp?
so people remove the stacks and put a regular exhaust cover on
to quiet it down? for just a collectors item to only be run
sparingly your advice? pipes or no pipes. i got to here it run
once with those pipes. it should make a super e or F classs
knee rider sound tame. i'll be gone for about two weeks
but i'll take you up on some of those photos when i get
ready to go together with it. the wrap around matches the top cowl.
thanks
david baker

[Mark75H]

Some Super E/FE's are louder than others, you'd be surprised.:)

[Raceman]

David, by the time I started going to the races in the mid 70's the old stackers were dead and I only saw a very occasional run by one on an old vintage sit down hydro. Most of the statistical stuff I post is based on comments by a friend who worked for Merc back then, along with his father, and was real familiar with all that 60's and 70's stuff, along with what I've learned from the motors I've accumulated and also talking with Sam C (Mark75H) who's VERY knowledgeable on the old race stuff. Anyway, one or the other of them told me that they were of the opinion that the stackers were sold as kits only and that complete motors never left the factory with them installed. I don't know firsthand if this is true or not. My Super BP does not have stacks installed, although I have 3 shortshaft 1350's with speedmasters that do. I think you'd enjoy running it a lot more without the stacks, or showing it more with em. Here's a picture of my boat if you've never seen it posted here before.

[OLEGATOR]

RACEMAN,
MY FIRST STACKER CAME AS A FULLY ASSEMBLED POWERHEAD. I HAD BEEN RUNNING A 1250 SUPER BP. THEY DECIDED THEY WANTED ME TO RUN THE 'S' CLASS AT THAT TIME, SO ALL I DID WAS CHANGE THE POWERHEAD. THERE WERE SOME DIFFERENCES IN POWERHEADS ALSO. WHEN I GOT TO PORTSMOUTH, OHIO ONE YEAR THEY HAD BROUGHT ME A DIFFERENT POWERHEAD. THE NEW POWERHEAD HAD MORE RADICAL PORT TIMING AS I REMEMBER.

[baker]

raceman, thanks for the pictures and info. my
cowling looks like yours color and style.
if you want to take the pipes off, what
exhaust cover do you use? one off a
135 or will any model fit. i think i want
to restore as pipe motor and then
possibly change it later. i'll see when i get
to that point.
thanks guys for the info

baker

[Raceman]

Baker, I don' t know the answer. Obviously a 70/71 1150 or 1350 should fit, but I don't know what others might also. I don't know when or if they made changes.

[MagicFloat]

When you run the Stacker your neighbors will try to have you arrested but it might be worth it to hear that song. When I get my Star with Quincy Stackers finished I know I will make some people upset but I will apoligize and move on,happy to have a little piece of history.A Stacker at full song has to be experienced, it cannot be described.

[T2x]

Having run in races with dozens of Stackers on hand, I can attest to the noise......especially when you were running behind Billy Don Pruett's triple stacker Jones.....

The stacks were available as kits for consumers, and as powerheads for "factory" guys ( in the 60's a loosely defined group including everything from major Mercury dealers to top racers to Mercury employee test drivers). The engines absolutely needed water injection, especially in single engine applications. There was enough torque to get the boats on slow plane but not enough (due to reduced back pressure in the open exhaust) to get them out of the water and up to race speeds. The water was sprayed directly into the elbows of the stacks using a button on the steering wheel or on the footrest which activated the water solenoid. You used this liberally during turns with a tunnel hull and especially coming out of turns away from the wind.

If you change your mind and want to sell that critter....PM me......before Raceman beats me too it;)

T2x

P.S. Raceman is that a current picture of what seems to be your twin stacker/Glastron Molinari?

[MagicFloat]

T2x,one Stacker is no good to you,last time I checked a Wing needs 2 motors,LOL:)

[2us70]

I had the chance to experience running in a much slower class than the Stacker boats. Being overtaken by several of them at a time in marathons took some getting used to. Sometimes it sounded like they were going to go right over you. But running a SE boat in such mixed company required your full concentration on what was ahead not behind so you just had to trust the guys driving those boats and run your own race. I would love to hear that sound again just for old times sake

[T2x]

Originally posted by MagicFloat
T2x,one Stacker is no good to you,last time I checked a Wing needs 2 motors,LOL:)

I plan on using it as an alarm clock;)

T2x

[OLEGATOR]

I HAVE A NEWSPAPER CLIPPING FROM THE MIAMI HERALD FROM 70 OR 71. THE ARTICAL WAS ABOUT THE NOISE LEVEL OF THE EXHAUST ON THE RACE BOATS IN THE 225. THEY HAD A DECIBLE METER AND IT RECORDED 125 DECIBLES. THIS EXCEDED THE LEVELS RECORDED AT SOME LIVE ROCK CONCERTS THOUGHT TO BE MOST DAMAGING TO THE HUMAN EARS. THE AMUSING PART OF THE ARTICAL WAS THE PHOTO THEY HAD. IT WAS BRIAN T2 ASLEEP IN HIS MOTHERS LAP IN THE GRANDSTAND WHILE THE RACE IS GOING ON.

[Raceman]

T2X, that picture does reflect the current condition of the boat. The solenoids were long since seized up internally, so were replaced with ball valves which were left wide open.

The boat is a Kitson rather than a Molinari and was still in the posession of the original owner.

[Mark75H]

Raceman, where does the water come from? Is there a hole in the mid or is it tapped off the powerhead?

[OLEGATOR]

THE WATER CAME FROM THE POWERHEAD ON ALL OF THE STACKERS I RAN.

[Raceman]

Mine too. Seems like it might be plumbed off the water jacket on the rear, but I'd have to look to be sure.

[OLEGATOR]

YOU ARE RIGHT RM THAT IS WHERE WATER CAME FROM.

[Raceman]

Here's a picture of it running. HalfAssed is the pilot. He wishes his STV would run with it.

[T2x]

Raceman:

Please, please bring it to Clayton next year........... Maybe we can get Mr. Kitson himself to come drive it....and what the heck is this Mt Dora event.... I might want to take a look at that.

T2x

[2us70]

How many of those 60s and 70s vintage race boats show up in Mount Dora?

[Raceman]

Jim, I'd sure like to see you take a spin in it. I've been gonna take it apart and make it purdy for several years and I think that'd be a prerequisite. In the present condition it makes the old Ragged but Rite Hydrostream look almost new.

It would be cool to have a picture of it with Kenny K drivin' it too.

I don't know how many of em show up at vintage events, but mine's never been anywhere. I rescued it from the original owner and he had it store UPSTAIRS in an old dairy barn.