compresion change over valve leak...

[fireram]

Good day,

I am trying to figure out how to stop the compression leak I am getting with my Comp, change over valve. I tried cleaning the plunger end to get it to seal better, but I still get leaks, no matter how tight I crank the handle.

Is the plunger just worn out, Am I missing some copper seals, if sio, where do they go??

When it cranks over, you can hear the air hissing in and out of the small holes in the large threaded part..

I tried putting a solid washer to plug the small hole, then cranked the handle, and she will fire right up, If I try to start it cold with the valve on low comp, I just cant spin it fast enough to start..  So I would really like to get it fixed..

Thanks very much...

[oliver90owner]

Remove and lap in the valve surfaces if on inspection the seat is easily recoverable.  Otherwise take whatever remedial action is required - re-cutting or replacing parts.

Regards, RAB

[Stan]

There's a copper washer in there I believe...check the manual for a diagram which shows where it is supposed to go.
Stan

[cujet]

Get rid of the COV. It is a waste of time, effort and reliability.

My engine has the machined plugs that replace the COV's. It's never run better!

Chris

[lowspeedlife]

Even better replace them with the cov plugs with glow plugs in them & you will never have "cold start" problems again! contact Phil at central maine diesel, They should have them in stock,


     SR.

[listerdiesel]

Get rid of the COV. It is a waste of time, effort and reliability.

My engine has the machined plugs that replace the COV's. It's never run better!

Chris

If you have an 8/1 then it is a different animal to the 5/1 and 6/1 engines, it runs faster and has a higher injection pressure.

Lister always recommended NOT to run the engine in high compression once started, ignore that at your own risk.

Lightly loaded engines can run in high compression, but anything more and it needs to drop to low.

Peter

[lowspeedlife]

didn't the cov plugs change the compression ratio to something between where the valve was screwed in & out?

     SR

[compig]

As I understand it , the combustion chamber was revised to lower the CR to 17.5:1 from 19:1