> What is your thought Tom, maybe he wasnt just sitting there at the light
> but dropping the clutch at 6000 revs. I have heard of the problem happing
> in this small place with non race as well as race engines.
Howard,
I think you are correct. In reality the jackshaft was ready to break,
due to high revs, but probably had the last little bit holding it on.
Damage was already done, and just picked that moment to fail.
A friend was really upset as he had loaned a dirt mulcher (turns up the
dirt for a flower bed) to a neighbor. The engine self destructed while
she was using it. He felt "she broke it, she should pay for it". Obvious
the neighbor didn't want to pay $400 for a broken mulcher. Once I stated
looking at it, you could find the crank shaft failure started long before
she borrowed the machine. Stress point, and lots of "beaches" across the
crankshaft were clear... New engine was $150, and she offered to pay half
if she could borrow the mulcher every spring. Kept them on good terms,
rather than "She broke it!" and having them made at each other.
So sometimes when things fail, they failure had started long before
you realize. Good idea to also have those jackshafts magnafluxed for
a race engine. If they snap at 8,000 rpm... enough momentum to keep
those gears and chains moving and doing all sort of damage to softer
aluminum. For the fellow who had it fail at a stop light... no engine
damage, as it killed the engine immediately (both distributor AND oil
pump will stop turning).
Cheers,
Tom Walter
Austin, TX
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