Hello I just bought this 1980 Glastron with a 230 hp OMC. I was getting ready to start up pulled the dip stick and darn milky oil. Looking at the exhaust manifolds the one all the paint seems gone the other still is painted. Could this maybe be why the water got in oil? Any help would be great thanks Randy
Hi Randy,
Welcome aboard.
Large amounts of water in the oil is almost NEVER from (cracked) manifolds or risers (leaking gaskets) . You can get some oil into cyls (from manifolds/risers) that could leak into open exhaust valves and past rings but it's on the order of table spoons, and if you run the engine very long, that little bit of water usually evaporates away.
Milky oil this time of year is most likely from a crack in the block that allows water from the cooling system to enter the oil.
The best most reliable way to inspect is to connect an air pressure source valve and gage to the block (after closing all openings) pressurize the block (15-20psi), close the valve, turn off the compressor and listen/look for leaks.
If the block is not cracked, it'll hold air pressure for a good long time. If you have a cracked block, you can usually hear it if it's internal and you can see it if it's external (spray a little soapy water on the outside of the block and you'll see bubbles where the cracks are if they're not obvious)
A manifold/riser appearing "burned" might indicate a plugged (with rust) manifold or riser water jacket. (time to replace them....both sides)
You may also have a bad raw water pump and/or plugged thermostat housing and associated hoses.
When was the raw water pump replaced last? If you cannot verify when the previous owner replace it, it should be replaced.
Also if you live where freezing temps are common in winter, the previous owner might not have drained the block sufficiently to prevent freeze damage (cracked block)
If you have a cracked block, you need to start looking for another engine.
230hp probably means V-8, if its a GM 350, you can likely replace that engine with a similar year 350 truck engine.
Finally, if you haven't paid for it, You might ask the previous owner to take it back.
Sorry about that,
Rick
