Need Engine Casting Number- Where to find? GM 4.3l/262/205hp

[frank1492]

The engine is on a !988 Grady White Seafarer- GM 4.3l /262/ 205hp. (OMC Cobra Sterndrive.) I hope this number is accessible before I pull the engine- engine is hydrolocked.
Does anyone know where the casting number is located? Thank you! Frank

 

[Scott Danforth]

casting number on all V6 and V8 GM vehicles is on the back of the motor, on the flywheel housing mounting flange on the RH side of the motor

your 1988 block isnt special. its just like any other 1988 GM truck 4.3 block

 

[frank1492]

So I gather the engine will have to be removed to see this number, not visible from inside the boat. ATK (the source of the remanufactured engine) apparently won't ship without the casting number. There are 5 ATK models (short blocks) that have descriptions that are slightly different. They are DM27,28,29 and DMC 4,7. I assume these are not exactly interchangeable with my engine and I don't know which to order (if I could.) Thank you so much for your reply. Any other ideas? Frank

 

[Scott Danforth]

look behind the starboard side cylinder head. easy to see.

you are over-complicating it. you have a 1988.... get a 1988 donor motor PERIOD. that way you dont have to figure out the 5 seriously major and hundreds of minor design changes over the years.

if you want to go inexpensive. get a running motor out of a 1988 GM truck (I use car-part.com) pull the motor apart, install marine head gaskets and brass core plugs. install all your accessories from your hydro locked motor - (I am assuming you pulled the spark plugs to get the motor to turn over). get new exhaust manifolds and risers. if you have the original batwing manifolds, that is what took your motor out.

 

[frank1492]

OK. So any 4.3L will work as long as it is specified as 1988 (or in a range including 1988), is that correct? I assume these were all carbureted engines with mechanical fuel pumps. So I may be assured that my carburetor and my fuel pump will fit on any of them? I think I am all set.
Yes I had the batwing manifolds. They lasted 8 years.
I should not have used the term hydrolocked, but we are assuming water did get into the cylinders. Here's what happened. The engine started to clatter, and I think I heard metal against metal when the engine died. The oil pressure was normal. When I attempted to restart, I could tell the starter was laboring in an abnormal way. It finally started and I was able to get back to the mooring (about 1/2 mile) with the engine sounding fairly normal except for missing cylinders. A compression test done later showed no compression in two cylinders.

 

[Scott Danforth]

your batwing manifolds probably have been leaking for a while. however if it was me, prior to dumping money on a new reman, I would pull the motor apart to see what is wrong and go from there.

with the 4.3, the changes over the year are enough to make your head spin. 1985 had its own block, 1986-1987 had their own block, 88-91 had their own block, 92-95, 96-00..... you get the point.

however since your boat could have an '87 motor in it, you still need to stick your head back there to confirm engine casting number. it should be 118676838 for the 1988