Hello fellow boaters, need your advice and help here.
My story, in short, I have a Wellcraft Prima 243, engine VP 5.7 GL with Holley carb. the boat was smoking a bit grey/blackish on start up for about 10 min for the past a few seasons, I thought it was due to the carburetor. This season also noticed that the oil became dark grey very fast and the level was a bit higher. A few days ago, when running idle at the slip engine stalled and I couldn't restart it again, first, I thought it was seized. Checked the oil level, it was about 2-3 inches higher than the maximum mark. After I pulled a gallon of contaminated oil I was able to turn the engine again. Then I pulled all spark plugs out, all plugs had signs of moister presence in all cylinders. I've drained all remaining oil, another 3/4 of a gallon, replaced the oil filter, and conducted a dry pressure test for all cylinders and a wet pressure test blowing fogging oil into the plug hole. The test shows 140 on two cylinders and 180-200 on the rest. The wet test shows 190-200 on all cylinders, including two with lower numbers. So, my question is what is the problem there, intake manifold, exhaust manifold/risers gasket, head gasket, head bracket, or worst-case scenario, internal crack in the block? And where I should start with a repair? I can do manifolds and risers gaskets, but going into deep is too much. It starts and runs well, a bit rough in an idle but acceptable. After running twice for about 10 min. the oil level rises about 1/4 of a quarter, but no signs of gross contamination or milky color of oil, it looks pretty normal yet. There are droplets of water and moister on throttle plates in the carburetor and a smell of gas from the exhaust, which indicates that fuel does not burn completely, probably due to moister in cylinders, and now I see why it was smoking. The mechanics in our marina are pretty busy now and it would take another week before they can get the boat into the shop, I was thinking to start diagnostic by myself, but wanted to ask the community first about your opinion. Thank you in advance.
My story, in short, I have a Wellcraft Prima 243, engine VP 5.7 GL with Holley carb. the boat was smoking a bit grey/blackish on start up for about 10 min for the past a few seasons, I thought it was due to the carburetor. This season also noticed that the oil became dark grey very fast and the level was a bit higher. A few days ago, when running idle at the slip engine stalled and I couldn't restart it again, first, I thought it was seized. Checked the oil level, it was about 2-3 inches higher than the maximum mark. After I pulled a gallon of contaminated oil I was able to turn the engine again. Then I pulled all spark plugs out, all plugs had signs of moister presence in all cylinders. I've drained all remaining oil, another 3/4 of a gallon, replaced the oil filter, and conducted a dry pressure test for all cylinders and a wet pressure test blowing fogging oil into the plug hole. The test shows 140 on two cylinders and 180-200 on the rest. The wet test shows 190-200 on all cylinders, including two with lower numbers. So, my question is what is the problem there, intake manifold, exhaust manifold/risers gasket, head gasket, head bracket, or worst-case scenario, internal crack in the block? And where I should start with a repair? I can do manifolds and risers gaskets, but going into deep is too much. It starts and runs well, a bit rough in an idle but acceptable. After running twice for about 10 min. the oil level rises about 1/4 of a quarter, but no signs of gross contamination or milky color of oil, it looks pretty normal yet. There are droplets of water and moister on throttle plates in the carburetor and a smell of gas from the exhaust, which indicates that fuel does not burn completely, probably due to moister in cylinders, and now I see why it was smoking. The mechanics in our marina are pretty busy now and it would take another week before they can get the boat into the shop, I was thinking to start diagnostic by myself, but wanted to ask the community first about your opinion. Thank you in advance.
