compression #'s for 1989 Evinrude 40

[bobjoe1]

Inherited boat and know for sure compression has never been tested. Nothing in service manuel as to what compression should be . I know there should only be about 10psi difference between the two cylinders but would an older motor have lower compression #'s. And what should they be.

 

[tashasdaddy]

Re: compression #'s for 1989 Evinrude 40

1989 is not an old motor. if mine i would like to see 120 on each, or higher. see compression testing, in the TOP SECRET FILE.

 

[psteurer]

Re: compression #'s for 1989 Evinrude 40

Don't get too alarmed if you do not get the 120 psi. The reason the numbers are not in your book is because all compression testers are different and will give you different readings. The key is as you say to have each cylinder within 10% or each other. It is rare for all cylinders to fail the same way so if you are within 10% you are almost always good to go.