Daniel asks:
> What are the pros-cons to reginding an old camshaft? They have to take
> off metal don't they?? Won't that change the profile of the old cam??
Somebody correct me if I'm wrong...
Yes, metal is removed - from ALL OVER. That is, the overall diameter
of the lobe is reduced. Camshafts work by the difference between
the low spot (base circle of lobe) and high spot. So the metal is
removed uniformly - the base circle is reduced, and the 'slop' that
is created is adjusted out with the valve adjustment on the followers.
Did I explain this well enough? If I could only sketch a picture...
After regrinding, the cam has to be hardened. Out of my field. There
are good techniques and not-so-good techniques, and the cam life
is very dependent on good hardening. The followers (aka rocker arms)
need to be replaced or at least resurfaced too - using a new cam with
a used arm, or vice-versa, will result in accelerated wear. You think the
cam is costly? Wait 'til you buy 8 rockers...
-- John
John F Sandhoff sandhoff@csus.edu Sacramento, CA
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