88' 70 eltg compression issue

[jujusboat]

I noticed that there is some oil leakage on the #2 cylinder while the plug is still in and carbon buildup behind the cylinders. replaced the sparkplugs and rebuilt the carbs several times. also there is a lack in compression on that cylinder the other two have good compression. can anyone let me know what else to try.

[boats.net]

If compression is more than 10 percent lower than other cylinder then it's too low.

[rscoggins 2]

You may have to rebuild the power head. The piston ring may be broke, causeing low compression. Did the motor over heat by chance or run out of oil? You can run with out that cylinder. Its just going run rough.
If you were near i would rebuild it for you.