454 Mag I have a real problem, I continue to show water in my oil, the boat was inside all winter and I installed a procharger on it during the winter, after the first time out I noticed I was showing water in the oil, I did a compression check and #1 cylinder was low, so I decided to pull the head, they reseated the valves, after I had the head and intake off I noticed alot of water in the upper galley under the intake, I have replaced the intake and head and the compression is back to normal but still having water problem, I pulled the carb yesterday and saw some drops of water inside the intake manifold, I am about to pull the engine, if anyone has any suggestions let me know.
Jim

You have to use silcone around the water ports of any marine engine. I had the same problem I put a blower on this winter didn't use silcone went out and had water in the oil all the time. Gets expensive when you are running synthetic oil. Took intake off and put this silcone called THE RIGHT STUFF. Make sure you put it on the top and bottom off the gasket just on the water ports.

OR you have a common blown head gasket leaking into the lifter valley where the extra head bolt holes are suspose to be to hold in the head gasket there,also the intake gasket doesn't know if its on a marine engine or snow engine it just means the intake does not fit right and your putting the silicone in to fill the void due to the improper fit ,be sure to use fel -pro head gasket and add 5lbs to the tourqe settings and use good bolts ,don't use more than twice ,so you need new now !!
you can buy different thickness intake gaskets to fill the void by the way from fel-pro ,but thats not a common problem

i have a blown motor and I all ways use silicone around the water ports on both sides of the intake gasket.

It seems to work, the only problem is if you ever have to pull the manifold you have to install new gaskets and clean up the heads at bit, worth the effort.