'81 Johnson 2hp - what should compression be?

[boarder1]

Going thru a tune up on a 1981 Johnson 2hp colt motor, and just wondering what kind of compression I should expect. I have not checked it yet but when I turn the flywheel over by hand it seems overly easy. I am assuming like most 2-strokes anything under about 85 psi would be low. Anyone know what I should expect?
thanks in advance.

 

[BigB9000]

Re: '81 Johnson 2hp - what should compression be?

Most outboard I have seen (under 10hp) all put out about 70-80.

..that or Im buying junk.

anyway, you can also turn them my hand pretty easy.

 

[steelespike]

Re: '81 Johnson 2hp - what should compression be?

Many times little 2 strokes are around 60 psi.

 

[phineas]

Re: '81 Johnson 2hp - what should compression be?

Thanks,,,, guys you answered one of my many questions too, I just tested my TD-20 a few days ago and I had 75 & 74, so I guess I am good to go that way at least.

 

[kbait]

Re: '81 Johnson 2hp - what should compression be?

Over 50 psi should run fine. Under that is iffy.. perhaps a decarb would help if the rings are stuck in the piston grooves.