valves worn out

[MUDDUCK]

i had alot of positive crankcase pressure and got tired of burning oil smell so i pulled the motor and tore it down. the worst cylinder was worn 4 thousanths and the hone marks are still there but the valves are shot, and the seats are good. 190,000mi any thoughts as why my valves are worn out?

 

[iracemine]

subbin

 

[JOAT]

Not a common problem. Are the valve faces eroded or just the guides have too much wear?

 

[MUDDUCK]

Both intake and exhaust have a worn ring on them and seats are good. machine shop said if they grinded them they would be paper thin. he asked if i was using propane. i haven't used propane. i got the truck with 137,000mi it was all stock, and i have keep up the maintance since i have owned it.

 

[JOAT]

My truck is running great at nearing 400,000 miles, average blowby, low oil consumption. I'd guess something happened to accelerate the wear in your engine. What jumps to mind is maybe an air filter problem allowing dust into the engine for an extended time. That would affect the valve faces and rings.