Engine knock

[lockmaster]

I have a 1800D Mitsubishi when it starts up the engine knocks but when the engine warms up the knock goes away. I have been told this is normal for my tractor and others tell me it has a bad piston pin. Has anyone else experienced this problem.

 

[Fawken]

Welcome. Sounds like pre-detonation since a rod knock is usually louder after things warm up. Oil pressure good? Change the oil & filter if no metal in oil, you're likely OK.