Compression

[8th of 9]

What should the compression be on a 1973 25hp Johnson outboard?
Thanks

 

[muskrat]

Re: Compression

Both cylinder should be about the same,but not more than 15psi difference..

 

[jonesg]

Re: Compression

What should the compression be on a 1973 25hp Johnson outboard?
Thanks

If its elec start 100psi+,

hand start is lower,
I can't pull mine fast enough to show more than 70psi.
But they need to be close, rather close than higher is better.
2 at 90psi is better than one at 90 and one at 140psi.

 

[JB]

Re: Compression

Both cylinders in a 10-15% (not 10-15psi) span. psi are irrelevant.

Check the Top Secret file for detailed instructions.

 

[8th of 9]

Re: Compression

Thank you all again for the helpfull info, I'm new to the outboard motors and have experience in automotive so I just have to get used to how everything is and should pick up a manual Thanks again, until next time, have a good day.

 

[tashasdaddy]

Re: Compression

parts diagrams here http://shop2.evinrude.com/ext/index.aspx?s1=86d3d72aeba35dacbc349b439cb45104