Can you identify a Mercruiser by the GM casting numbers?

[manyolkars]

I've spent a lot of time searching the internet with no luck.  To keep this simple, there is NO boat, NO ID plate on the block.There is a serial number V04024CN on the correct boss on the block near the fuel pump.  There is a block casting number---GM3937746.    This engine may have triple the horsepower of the Model A engine and may bolt in with the standard aluminum adapter.  I'd like to hear from anyone who knows if the adapter will work for this. The block has the smallblock chevy bellhousing pattern.  Thanks!  Bruce Wayne

[enjenjo]

This one is hard to pin down. the casting number was used on both car and marine engines as far as I can tell. Cars to 70, and boats much longer. If the bell housing bolt pattern is the same as a small block it should bolt right up either way, boat or marine. HP rating should be about 120,  153 CI. I got this info off one of the Boat sites, and what I could find in my hollander.  According to the serial number, it was assembled by GM, and not one of the marine builders.

[manyolkars]

Enjenjo to the rescue!  Thanks Frank!    Where did you find info on that serial number?  Everything I found had straight digits, no letters.     Which boat site?      Could this engine be bigger than 153"?    I will be Very happy with 120 hp, just curious.   This engine was in a boat and still has boat mounts, fuel pump, and that thing on the flywheel.  I like how you say it could be either boat or marine!------------>

it should bolt right up either way, boat or marine. .

[enjenjo]

Should have been car or marine, but at least you got a chuckle :oops:

According to what i could find, that block came as 153 ci only. If assembled by Mercury Marine, the serial number only had two letters. The ones with letter prefix and suffix were assembled by GM for use in cars, or for marine use. I speculate marine, because I can only match the suffix in my books.

[manyolkars]

120 hp otta make the Model A run!

[48ford]

I'm looking at a old boat repair book,and the motor came in both 153 and 181 cid.
The serial number is located on a plate mounted on the right rear side of the block above the starter.
You can call or stop by your mercruiser dealer and he can tell you just what you have.
the motor used a 4 cyl chevy block and it will bolt up to the adaptor.
I have never seen one that had extra bosses or a special casting,so motor mounts ect. should be the same.
hope this helps
Russ

[manyolkars]

I'm looking at a old boat repair book,and the motor came in both 153 and 181 cid.
The serial number is located on a plate mounted on the right rear side of the block above the starter.
You can call or stop by your mercruiser dealer and he can tell you just what you have.
the motor used a 4 cyl chevy block and it will bolt up to the adaptor.
I have never seen one that had extra bosses or a special casting,so motor mounts ect. should be the same.
hope this helps
Russ

Thanks Russ. All the info I find sez ID plate by the starter, but I have 2 of these engines and neither has a plate by the starter. I SAW one motor in the boat and was told by the previous owner the other was in a bost.
I was wondering if this could be a 181.   You know, more is better and too much is just right!