Proping Question
On Sat, 19 May 2007 01:13:55 -0400, Jose
wrote:
The crank has a ratchet and will
free wheel if the engine pops backwards.
How would that work? The engine going backwards against the crank
imparts the same (direction) force as the crank going forwards against a
recalcitrant engine. That would freewheel too, defeating the purpose.
A simpler version of the ratchet: The way it worked on my '41
McCormick-Deering tractor (sorry Cubdriver, mine had rubber tires),
the crank and the socket were machined with matching flats and
matching ramps. When you were applying torque to start the engine,
the flats were in contact, but when the engine started, the slanty
bits slid past each other and expelled the crank.
But if that sucker tried to run backward, the flats would continue to
engage and the crank handle would do something nasty. Not that it ever
tried that on me.
Jose's right.
Don
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