K-341 "pinging"
 

I found a 1650 to start building a herd. Here's what the owner says "It did run about a year ago, it started to ping real bad when I was cutting the grass. I think a valve went bad." Any ideas what would cause a "pinging"?
Thanks

Pinging is pre-ignition. I would clean the head and remove carbon. Adjust carborator and check timing.
Make sure the cooling fins are clean or that will cause overheating and pinging.

Michael