73' Rude Compression

[rather_be_boatin]

Does anyone know what the compression should be for a 73' Evinrude Yactwin? I've got 85 on both cyls. Wondering if that is low for the make & model??

 

[tschamp20]

Re: 73' Rude Compression

sounds low. what h.p.? maybe try a decarb.might be stuck rings.look in faq section for decarb instructions.you might get lucky for $10

 

[iwombat]

Re: 73' Rude Compression

The compression should be enough to make your engine run right.

Really, there's no definitive answer. They're even and that's good. As for hard numbers, that will vary greatly with the gauge. I've got two gauges that disagree by 30psi. I've calibrated them both and the best one is still 10psi low from the dial on the calibrator. Bottom line - pretend the numbers aren't there and just look for them to be even. Your motor will tell you when it's worn out by having a hard time keeping idle, and losing power in the top end.

 

[rather_be_boatin]

Re: 73' Rude Compression

Thanks. It does not idle. Plenty of top end power and is nearly impossible to start. Might be ready to send her to meet davey jones locker... I've had very poor luck with this engine.