[E.J.H]

So we have 2 420's 1 crawler and 1 utility and on both of them we have rebuilt the engines however we can not keep the valve cover gasket to keep from leaking... Tightened to proper torque and then the gasket swells and starts leaking as soon as oil makes contact. I will try to send a picture of what I mean. any advice is greatly appreciated!!!!

 

[Dan in Ohio]

I don't think it is the head gaskets fault as the head on those dubuque tractors are prone to warpage. If those mating surfaces are not machined flat they will leak.

 

[E.J.H]

So your thinking maybe my head is warped? It has had a brand new head with in the last 2 years. but not throwing it out of the question