92 Diesel Dude
10-06-2003, 22:46
Hello, I am currently inspecting a set of cylinder heads with 15000 kms on them and have noticed that the pre-cups are basically a Size on size to a light sliding fit in the head pockets. They can be removed fom the head with very little force, generally the weight of a small brass punch. These heads were fully re-conditioned with new springs, hardened seats, collant passages tubed, but reused precups. However there is the recomended cup protrusion .003" and the stress cracks are within the fire ring.I am concerned because I expected a tighter fit in the head bores . What is the recomended interferance? Have short cuts been taken on my heads? It is obvious that the edges of the cups have had 4 center punch marks peened on to them to correct the fit problem.I've been machining long enough to know that this is far from professional, for advertised professionally quality controlled heads. I won't say at this time who the vendors are.
Regards.
Regards.