Re: Water in Oil - Mercruiser 5.7/Alpha 1
Before you flip a coin and tear off a head, there are two tests that might help narrow this down. I have to underline might. The first would be to pull the lower hose off of both exhaust manifolds and plug the hoses, then pull the hose from both risers and plug those hoses. Next connect a garden hose to the water inlet hose that is normally connected to the outdrive.Remove all spark plugs and remove both valve covers. Turn on garden hose just a little, leave hose a little loose where it connects to faucet ( the idea is to have enough preasure to make large hoses on engine feel a little firm, but not blow anything).<br />Watch for any signs of water around heads and from spark plug holes. If nothing after a few minutes, turn engine over slowly again looking at spark plug holes for any signs of expelled moisture.<br />Another test that might tell you something: If you have access to compressed air and have a hose adapter that will screw in to a spark plug hole<br />( I use a detachable compression tester hose with the check valve removed), you could do the following:<br />Remove valve covers, loosen all rockers, with all spark plugs out, one cylinder at a time connect compressed air, listen for where air is leaking. If anything sounds suspicous, you could also remove the thermostat housing and watch the water to see if it rises or bubbles at any point. Also be on the lookout for leakage from one cylinder to the next.<br />In more than one case this test has helped me to localize or narrow down where to look. One case I had a very small corroded hole from the cylinder wall to the water jacket, engine still ran fine but was sucking a small amount of water into cylinder and was ending up in oil.<br />Another case was a blown head gasket. And still another a hairline crack in head.