Ok here is some more fuel for thought. Back to one of Dave's favorite subjects
oiling.
Bill
>
> From: Jerry Davis <jerry.davis@arcnc.com>
> Date: 2003/02/20 Thu AM 08:57:14 EST
> To: 'Bill Pokey Bennett' <bennevl@bellsouth.net>
> Subject: RE: Motor Autopsy
>
> Hey Bill,
>
> Hydraulic lifters....hmmm. It was stated that there were some valve marks on
> top of one of the pistons. Would this happen to be the piston from cylinder
> #1 or #2? If the lifters over-pumped I would expect there to be bent push
> rods, so I really suspect that the lifters were starved for oil creating
> valve bounce, or if there was sufficient oil for the lifters, the check ball
> in the lifter probably was not seating at base circle of the cam (due to the
> high RPM) therefore it could not sufficiently charge the lifter. When lifter
> leak-down increases, the shortened lift allows the valve to hit the valve
> seat before being adequately slowed down by the closing ramp of the cam. If
> the RPM level was maintained long enough, the separation increased to the
> point where the lifter was hammering the cam lobe and "voila" catastrophic
> failure.
>
> Take care,
> JD
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