Bob Fuller, John Twist, and any T-typers out there...
For the last few years, I've had an unusual amount of wear creeping into my
valve rockers. The underside of the tip where it strikes the valve becomes
dished out. I have only a few thousand miles on the latest set of rockers
and have already seen 4 of them getting worn and two more getting scuffed.
It appears that the ones suffering the least wear are the ones with the most
amount of metal thickness on the tip. This leads me to believe that the
angle of the tip face to the valve tip is crucial. The rocker face needs to
squarely strike the valve, not angled to catch the sharp edge.
In fact, on the way back from the GOF last summer, I broke a valve tip. I am
now speculating that this was caused by previous rocker tip regrinds left so
little metal that the rocker was not striking the valve on top so much as
hitting it at an angle.
I'm not a master mechanic or an automotive engineer. I'm only trying for a
trouble-free TD. Since rockers are almost non-existant for a TC/early TD,
and the few available selling for over $75.00 apiece, I have the following
questions:
1) Does this seem like a reasonable explanation for the premature wear and
possible last year's broken valve?
2) Can old rockers be built back up to the correct profile?
3) Who is likely to be able to do this work, and what is a reasonable cost?
4) What is the "correct profile"?
5) Can this surface be hardened? (I have had a few rockers filled in with
stellite weld and ground, but they too didn't last. I believe the striking
angle may have already been past the optimal).
Any help and advice would be appreciated.
Regards,
Lew Palmer
lew@uci.com
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