J
Jack Klarich
Guest
I am by no means as knowledgeable as the HD mech. you spoke to, but I have to agree with Jack. It has been my experience that something loose in the piston usually sounds like a thud or slap. I don't think I have ever heard a loose or broken valve guide, but the motion would seem like a high pitched squeal could happen. I'm still thinking that the head gasket leak is possible. Please let us know how this turns out. Best of luck.
Another good point Don, a compression / leak down test before dis assembly would not hurt