Restored a C-160 for son-in-law. Didn't do any engine work on the K341 other than adjust the valves.
He has put about 12 hours on it this year and then yesterday, after mowing for quite a while, the RPM's jumped up very high and smoke started pouring out of the breather. He shut it down immediately.
I was over there today and we tinkered a bit. He had already adjusted the governor. Started it up and at low RPM it didn't smoke but I did notice a knock.
Revved the engine to 2500-2800 RPM and the smoke came pouring out of the breather again.
Oil level is fine. The knock certainly is concerning as is the smoke.
Any suggestions short of a tear down? Thanks!