Re: I/O Merc 2.5 Blown. Can I use a 2.5l block from an S10???
Are you sure it's blown?
What are the symptoms -- could just be a gasket or something -- these engines usually rot out before they wear out or blow out --
Sorry, you can't use an S-10 block -- it's totally different technology..
The boat 2.5 is the "stovepipe" design whereas the truck version is the "iron duke" design..
The head deck on the boat engine will not match up to the block deck on the truck engine..
The push rods are in slightly different locations and move at a different angle..
The cam is an automotive cam and the marine cam from your boat block won't fit..
Now that said, if you can find an old '60's chevy II nova with a 2.5 (or 3.0) 4 cylinder, THAT engine would work -- just swap your marine cam in (I'd recommend using the lifters from your marine block as well since they are worn in to your marine cam -- keep them in the same positions), install brass freeze plugs, and swap your oil pickup tube and oil pan onto it.. DO NOT use automotive alternator, starter, fuel pump, or carburetor....
Hope this helps...