Low compression

[Dirty Worm]

Looking at a 1999 20ft Aquasport CC with a 150 Johnson 2 stroke Ocean Pro.
Compression test showeed 115psi in all 6 cyl.
Im used to seeing about 135 psi. Is 115 psi too low? Does that mean the rings are going?
Its the only reason I did not bring her home with me. It did seem to blow alot of smoke on start up but its been sitting a few months.

 

[Monte1961]

Re: Low compression

Run a bottle of seafoam and then recheck compression. Carbon may have gotten rings hung up around the lands. Post back results.

 

[hidef]

Re: Low compression

115 across all 6 cylinders are good. Two strokes are going to smoke a lot if the engine was fogged before being stored. Even when they are cold they tend to smoke until warmed up it is the nature of the beasts.

 

[boobie]

Re: Low compression

As long as they are that close together don't worry about it. Everybody seems to forget that compression gauges vary. I have 5 of them and I can put each one on the same cyl of a mtr and get different readings.

 

[Dirty Worm]

Re: Low compression

Thanks for the info. Sounds like 115 all around is nothing to worry about. Think I'll pull the trigger.