Hello all,
Another victim of lifter and cam lobe failure was shown to us last evening
at our monthly Southern Ontario pub nite. A good friend's 100M fitted with a
new Dennis Welch cylinder head which came complete with valves, springs,
guides, etc. The camshaft was fresh at the time of assembly and all cam
followers were in excellent condition. It has been on the road for 3 seasons
and 12000 miles. Valvoline 20w50 has been used all along and changes were
regular. This car is very carefully maintained.
To me it brings a number of points to mind:
1. Three years ago when the engine was being gently broken in, would there
not still have been sufficient amount s of ZDDP in the Valvoline oil?
2. What are the spring rates of the Welch head assembly?
3. Not all lobes or cam followers eroded at the same rate. Some are almost
still okay while others (#5 especially) are completely broken down.
This is getting scary, but I think all avenues should be carefully explored.
Rich Chrysler
----- Original Message -----
From: "BJ8Healeys" <sbyers@ec.rr.com>
To: <healeys@autox.team.net>
Sent: Thursday, May 10, 2007 6:53 PM
Subject: Valve job
> Hello, Healeyphiles -
>
> Thinking that my BJ8 was in good shape to begin the trip to Conclave at
> the
> end of June, I was very disappointed to find that I have low compression
> in
> two cylinders, 50K miles into an engine rebuild. Seems that two rockers
> had
> no clearance, either.
> I haven't yet pulled the head (waiting for help in lifting it off), but
> anticipating a valve job I wanted to ask how many new parts I should plan
> on
> replacing besides the gaskets. At the engine rebuild, all of the head
> studs
> and nuts were new. Can I reuse them this time?
>
> All of the valves, guides, springs, etc. were new, too. Can I reuse
> them,
> assuming they look O.K.?
>
> I appreciate all advice. Thanks,
>
> Steve Byers
> HBJ8L/36666
> BJ8 Registry
> Havelock, NC USA
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