Can a lean AF mixture cause valve to sink in a 2f? (1 Viewer)

[haryv]

This is just a general question for these engines. This happened to me on another car LONG time ago when lead was still in gasoline. I had purchaced a car where the high speed jets were to small for highway speeds. Over time, engine performance started to degrade. After I found out the carb was jeted with to small of jets, the lean air/fuel mixture attributed to to high flame front mixture, leading to the valve getting way to hot, as well as the seat, causeing it to sink into the seat. Can this happen on these old 2f engines?

 

[lehiguy]

This is just a general question for these engines. This happened to me on another car LONG time ago when lead was still in gasoline. I had purchaced a car where the high speed jets were to small for highway speeds. Over time, engine performance started to degrade. After I found out the carb was jeted with to small of jets, the lean air/fuel mixture attributed to to high flame front mixture, leading to the valve getting way to hot, as well as the seat, causeing it to sink into the seat. Can this happen on these old 2f engines?

I think that can happen to any four-stroke engine given enough time and heat. I too have seen that.

 

[specialk396]

Burning exhaust valves from a lean mixture is a common tuning-related engine failure. Most common on carb'd engines. Usually you will notice the glowing exhaust, its a big tip-off.