Help me identify these two Merc V6s

[gregpro50]

I'm kinda new to the Mercury V6 motors. I've screwed around with the inlines for years but I'm not sure what I am looking at with these. I bought these motors as a pair from a member here hoping to put one on my Varmint. Both have the lightweight Bridgeport cowls on them and I am pretty sure the midsections were changed. They both have the three ram trim systems. I can't find any meaningful numbers anywhere on them. Certainly nothing that looks like a serial number. They were on a twin engine setup but the head patterns are different so they must be different motors.

Here is mystery motor number 1:

http://i275.photobucket.com/albums/jj306/gregpro50/P5071567.jpg

http://i275.photobucket.com/albums/jj306/gregpro50/P5071568.jpg







And here is mystery motor number 2: The gentleman I bought this from thought it was a 225 due to the head pattern matching the '81 225 he has.

http://i275.photobucket.com/albums/jj306/gregpro50/P5071569.jpg

http://i275.photobucket.com/albums/jj306/gregpro50/P5071570.jpg

[tlwjkw]

Top one is probably '85 or '86 200. Fuel pump is a clue. Next is a pre '83 first generation block 200/225. Can't see tha reed block well enough. More than likely a 225. Three ram tnt came out in '85 on production motors. Look for tha build date behind tha timing arm..........T

[gregpro50]

The reed block on the second one looks identical to the first one.

The number behind the timing arm on the first one is 1 584

The number on the second one is very hard to see because it wasnt stamped good.
It is either D201 2
or
D281 2

What confused me is that I thought the early 225 Mercs had unique heads to them but the heads on the second motor shown match the ones on the '79 200 that is on my Vector.

[tlwjkw]

Bolt pattern is tha same on all first generation 150 ta 225's ('76 ta '82/'83 I think). Don't think thats tha build dates. Look at tha base of number 2 clyinder, just ta tha right of tha number your seein' on tha case half. Reed blocks LOOK tha same at first glance but ya hafta look at tha number of bolts holdin' tha reed cages...........

[Way2slow on H2O]

Don't think thats tha build dates. Looks close enought to me :D

The 225 heads had the slight angle cut on the squish. :thumbsup:

[gregpro50]

There are no other numbers by the arm. I pulled the whole damn arm off to look. I see what you are talking about with the bolts. The second motor seems to have more.

[gregpro50]

The 225 heads had the slight angle cut on the squish. :thumbsup:

What the hell does that mean? Is squish a technical term? LOL

Do these look like 225 heads to you?

[cutwater]

Greg,

I have a 1981 V225. It has the diamond shaped 2 piece heads like in your photo of engine number 2. The cylinder head bolts attach to the cylinder liner, that design was changed from 1983 on, from my research. Also, about that time, the HP rating changed - from the flywheel to the prop, so the 225s became 200s.

My block is the 5 bleed line design, no bleeder on number 3. On number 5, where the bleed line connector is, there is a stamping in the block - an arrow pointing where the 90 degree fitting should point, and "V225" stamped next to the arrow.

My intake was changed at some point to a 5 petal, 7 was original.

Just took it apart this winter, cleaned it up, new rings and seals to freshen it up. I've got a lot of photos of it along the way, PM me with an email address if you need any.

[tlwjkw]

Think he's talkin' 'bout tha inside on tha "squish". Its tha way tha combustion chamber is cut on tha inside. No difference on tha outside. Those are probably tha right dates. May '84 (probably sold as a '85 model, oil injection) and Feb. '81. '81 is probably a 225.............

[gregpro50]

OK I am starting to understand. So both these motors should be 200hp at the crank.

Are both of these chrome bore blocks? My repair manual mentions something about anything over 175hp is a chrome bore.

[gregpro50]

Greg,

I have a 1981 V225. It has the diamond shaped 2 piece heads like in your photo of engine number 2. The cylinder head bolts attach to the cylinder liner, that design was changed from 1983 on, from my research. Also, about that time, the HP rating changed - from the flywheel to the prop, so the 225s became 200s.

My block is the 5 bleed line design, no bleeder on number 3. On number 5, where the bleed line connector is, there is a stamping in the block - an arrow pointing where the 90 degree fitting should point, and "V225" stamped next to the arrow.

My intake was changed at some point to a 5 petal, 7 was original.

Just took it apart this winter, cleaned it up, new rings and seals to freshen it up. I've got a lot of photos of it along the way, PM me with an email address if you need any.

I'll have to check that out. The one I have has been repainted and it makes it hard to find any numbers. I'll have to take some sandpaper to that area.

That is what I am planning for mine is to freshen it up over the winter. I'll take you up on the picture offer here soon.

[cutwater]

I think both should be 200 at the prop. (225 at the crank)

My v225 is chrome bore.

Is the button gone on the top rear of the block that has the serial number on it? Mine was there, but it was so painted over and gunked up with grease that I couldn't read it until I took the motor apart to clean.

[gregpro50]

Sorry I meant to type prop HP...

There are no numbers on the plug at the top. That is the first place I looked because they are all there on my inlines.

One interesting note I just discovered was that there is a stamp on the case split right by the electronic boxes that says REBUILT BBM.

I'd bet at some point these were probably both '85 200hp motors. At one point the port powerhead went bad and must have been replaced with this rebuilt one.

[jimmyz32]

:iagree: cutwater is correct the first motor is a 1984-86 2.4 200 chrome bore and the other is a late 1970's-1983 2.4 225

[jimmyz32]

no oil injection is pre 1984 the second power head has no oil injection hole.

[gregpro50]

Another question. I read somewhere that you cannot hone or bore a chrome bore motor. My manual says that if a cyl has gooves in it then you have to replace the whole block. This sound right?

So assuming there are no grooves in the cyls do you just slap some rings on the pistons and call it good?

The compression on both motors isnt too awful bad. I didn't do a bleed down test or anything though. They havent run in a long time so I wanted to pull them apart to freshen them up.

[jimmyz32]

I would hone my chrome bore motors with a green scotch brite pad just enough to get the goldish brown off or you could use a ball hone but no porting. If ya blow it up they just put steel sleves in it.:thumbsup:

[cutwater]

I read that you can't really hone chrome like a steel bore motor, but like Jimmyz said, you can scuff with scothbrite. Jay Smith might have said the same, don't remember. Anyhow, Bob Garone of Marine 2000 coached me through the freshen up, he agreed on the scotchbrite idea, put net rings in and go. I also did seals, checked out all bearings, etc. There were even divits in my cylinder bores, I posted pics, everyone that responded said they were original casting flaws, let them be.

[gregpro50]

Great. Thanks for the info everyone.

Right now I am trying to separate the powerhead on the first motor and it is fighting me every step of the way. I've used every trick in the book but corrosion has practically welded it to the mid section with the long bolts. Right now I am drilling throught the exhaust plate with a hammer drill to drill through the bolts so I can separate it. Then I'll just weld up the holes and have to find new bolts... Fun.