Reply To: Johnson TD-20

[Buccaneer]

If the compression was 68 on both cylinders, then it would be a decent
“idler”. Between the “spread” in compression of 8 psi, and 60 psi
on the lower cylinder, it will run, but may not idle good.
Could a ring be stuck on the 60 psi cylinder?
If lucky, it could unstick itself after running it a few times.

I’m guessing you’d have to make new gaskets for the Neptune,
but a good thing to learn if you like old outboards.

Prepare to be boarded!