Thanks Wolfman,
I guess what I am missing is why increased clearance (due to gear wear) would cause the starter gear to have difficulty engaging.
Seems like it should go in easier rather than not. Assuming that the starter/solenoid unit is in good condition.
In other words, when things are new and tight it engages fine. Why would extra clearance be an issue? Just seems like the system should continue to work until things are worn to the point where the gears will not engage anymore.
Obviously something does happen, if replacing the flywheel ring gear cures the problem. Perhaps wear changes the force vector, causing the starter to jam rather than push the ring gear in the direction that causes flywheel rotation...bet that is it...but I never win bets.
Edit: I think I see the answer. The diameter difference between the two gears is huge. As the large gear wears, the starter gear has to turn further before it reaches the point where it applies force to the ring gear teeth. It probably wears to the point where the force is applied in a direction at an angle away from the direction of rotation, to the point where the gear binds rather than rotates the flywheel.
My best guess anyway...
I guess what I am missing is why increased clearance (due to gear wear) would cause the starter gear to have difficulty engaging.
Seems like it should go in easier rather than not. Assuming that the starter/solenoid unit is in good condition.
In other words, when things are new and tight it engages fine. Why would extra clearance be an issue? Just seems like the system should continue to work until things are worn to the point where the gears will not engage anymore.
Obviously something does happen, if replacing the flywheel ring gear cures the problem. Perhaps wear changes the force vector, causing the starter to jam rather than push the ring gear in the direction that causes flywheel rotation...bet that is it...but I never win bets.
Edit: I think I see the answer. The diameter difference between the two gears is huge. As the large gear wears, the starter gear has to turn further before it reaches the point where it applies force to the ring gear teeth. It probably wears to the point where the force is applied in a direction at an angle away from the direction of rotation, to the point where the gear binds rather than rotates the flywheel.
My best guess anyway...
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