Compression relief valves leaking oil on 1957 35hp Johnson RDE-19

[oldfarmall]

Hello-

How can I get my compression relief valves to stop leaking oil on my 1957 Johnson RDE-19 35hp motor? The bottom cylinder is the worst, leaks down cylinder head and into motor cover, then down outside of exhaust leg. These valves are not in use anymore, all linkage has been removed as I have electric start. Is it possible that I am losing compression too? Motor runs great now, just leaks oil. Any help would be great. Thanks!


Jesse

 

[F_R]

Re: Compression relief valves leaking oil on 1957 35hp Johnson RDE-19

The oil can't get past the valve if it is properly seated in the head. One cause is lack of clearance with the rocker, but since you have removed all that, it isn't the cause. Next step is pull the cylinder head and reseat the valves. Probably just carbon. They don't really "wear" like a 4-stroke valves. There also is an o-ring on the valve stem, replace it while you have it out.

 

[oldfarmall]

Re: Compression relief valves leaking oil on 1957 35hp Johnson RDE-19

Thanks for the reply F_R!

I looked at my parts book and can't find the o-ring. Do you know the part number, or is it just a standard o-ring I can get at the hardware store? Thanks!


Jesse