I'm helping my buddy fix up a free boat he got, a 1977 17' Seaswirl tri hull with an OMC 120hp inboard. It's a POS, but we're trying to have some fun with it this summer. (I plan on buying a boat after the season is over) We took it out today and it seems really underpowered. It tops out around 28mph and just over 4,000 RPMs, and really struggles to get on plane. We tried to pull a tube and it could just barely do it. I don't think it could get a skier out of the water.
The engine seems to run really good. It always starts with a little bump of the key, idles nice, and sounds good. We plan on testing the compression tomorrow but I'm afraid it's going to be low. There is a bit of smokey blow by coming out of the CCV. We replaced the plugs/cap/wires and gave it a heavy dose of Seafoam. (both in the gas and in the carb)
Is there anything else we can check? Maybe the carb needs to be adjusted? If the compression does turn out to be low, are there any band aid fixes we can try? I plan on putting some 20w50 oil in it. Anything else we can do? At the end of the season we plan on stripping it for parts and cutting it up, so we don't have much to lose...
The engine seems to run really good. It always starts with a little bump of the key, idles nice, and sounds good. We plan on testing the compression tomorrow but I'm afraid it's going to be low. There is a bit of smokey blow by coming out of the CCV. We replaced the plugs/cap/wires and gave it a heavy dose of Seafoam. (both in the gas and in the carb)
Is there anything else we can check? Maybe the carb needs to be adjusted? If the compression does turn out to be low, are there any band aid fixes we can try? I plan on putting some 20w50 oil in it. Anything else we can do? At the end of the season we plan on stripping it for parts and cutting it up, so we don't have much to lose...
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