1958 50hp evinrude compression reading

[Isaacm1986]

A friend of mine has a 1958 evinrude, 50hp short shaft V4 motor. It starts and runs great. Rev's high, idles low. We ran a compression test this morning on it and the numbers seem a little low to me, but I wanted to ask you guys.

Cylinder 1-4

1. 85psi
2. 90psi
3. 90psi
4. 80psi

What do you guys think? I did spray WD-40 in each cylinder before the compression test.

 

[F_R]

Re: 1958 50hp evinrude compression reading

Sounds good to me.

 

[JB]

Re: 1958 50hp evinrude compression reading

Me, too.

 

[Isaacm1986]

Re: 1958 50hp evinrude compression reading

Very cool, That is good to hear.

The compression on my 78 evinrude 115hp is 130psi on all cylinders. So those numbers seems low to me, but it is a lot smaller motor as well.

thanks guys!

 

[Isaacm1986]

Re: 1958 50hp evinrude compression reading

does anyone know what the original compression rating was?

 

[F_R]

Re: 1958 50hp evinrude compression reading

does anyone know what the original compression rating was?

Nope, it was never published by the factory.