RE: OS 61SF Idle Problems
alaflyer,
I did read this thread for a while and have this simple question, “Do you use an electrical starter motor?” (or maybe I did not read it?)
Why this question?
When not using an electrical starter motor, starting by hand, the first problem of a bad piston liner set is, you are not even able to start the engine (without tricks).
If you use an electrical starter motor you can start the engine with bad compression, but the engine will have a bad behavior in low revs. Exhaust gases will enter the crankcase and destroy the breathing.
I always start my engines by hand and so do have a good feeling of the compression.
So, how is the compression, the quality of the piston and liner? Maybe a bad pistonring if there is, or the ring locked? in the groove of the piston or a groove in the liner.
Mechanical condition is the first important fact to check.
Another important check is also the fit of the crankshaft in the crankcase. Maybe the engine did his duty for a while in the past with bad bearings so there is too much leakage?
If I missed a post about these subject, than I am sorry. good luck,
Cees