I recently had problems with my bobcat 643 losing power and no running smooth so I got the aid of a mechanic and he listened to the engine ( 3 cylinder kubota ) and swore that it had a bent valve. I believed him, idiot, and instead of paying the enormous price to have him rebuild it i chose to buy a new head and replace thinking that would be quick and less costly. I changed out the head by the manual and had everything correct. New gasket set used. Bled lines and it started and ran great until the thermostat opened and it proceeded to fill the intake manifold with antifreeze. Why would this happen HELP
Defective head
A couple years ago my 773 started runnin bad and i thought it was a valve or head gasket. Took the head off and with a few simple tests everything looked ok so i moved on. Come to find out #3 cylinder had cracked rings and was looseing compression. So I rebuilt the engine and put my head back on it,,, so runnin good today. Good luck, Billy