Ring gear.

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36inter
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Ring gear.

Post by 36inter »

I bought a high torque starter motor, the engine it has a flywheel from the 60's and I have never had any trouble with it other than old tired starter motors, hence the high torque one. However after fitting it the car started ok but made a horrible whirring noise which eventually I decided the gear on the starter motor was not disengaging from the ring gear and was wizzing round, only disengaging, I think, when the engine was stopped. I put on an old standard starter motor and although a bit lazy was quiet when started, no whirring. Hmmm.

So I counted the teeth on the ring gear, twice and got 108 teeth, totally confused now, anyone any ideas?

Thanks.

Pete
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Re: Ring gear.

Post by mk1 »

Sounds like you have inertia Starter & Pre engaged starter mixed up.

Most of the high torque starters are for the later Pre Engaged fly wheels. You can't mix the two up.

You can convert an early flywheel to pre engaged by replacing the ring gear with one of these.

http://www.minispares.com/product/Class ... |Back%20to

Or of course by replacing the flywheel altogether.

Or finally you can but an inertia high torque starter.

http://www.minispares.com/product/Class ... o%20search
36inter
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Re: Ring gear.

Post by 36inter »

Thanks Mark, the starter is a high torque inertia starter from Mini Spares. The ring gear is on a spring clutch flywheel not a diaphragm clutch and I havd never replaced the ring gear. Prior to my ownership it may havd been done. Its the 108 teeth (double checked) that has thrown me, I thought ring gears were either 107 or 128. A standsrd inertia starter motor works, but the one I have is a bit lazy.
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Re: Ring gear.

Post by mk1 »

Hum, Puzzling.
bwaminispeed
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Re: Ring gear.

Post by bwaminispeed »

For lazy starters, quite often it's a ground problem, not the starter........
36inter
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Re: Ring gear.

Post by 36inter »

Thanks for that, I thought about that last night, my engine is in a special and has different engine mountings and is pretty isolated, the job this morning is to add a direct ground to the engine, I will let you know how I get on.

Pete
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Re: Ring gear.

Post by 36inter »

Oh, and I counted the ring gear teeth again....still 108 teeth!!!
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dodge44
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Re: Ring gear.

Post by dodge44 »

Have you tried a 10-tooth bendix on the starter vice the normal 9-tooth? That might resolve it.
36inter
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Re: Ring gear.

Post by 36inter »

Thanks for the nudge about the earth to the engine, put that in place and the starter workd fine, even on 108 teeth, I guess the original style starter is more tolerant than the High torque one which is much better engineered.

Pete
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Re: Ring gear.

Post by woodypup59 »

You must always have a proper earth strap onto the engine, otherwise its earths through the drive shafts potentially pitting bearing surfaces - or through the choke / accel cables.
bwaminispeed
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Re: Ring gear.

Post by bwaminispeed »

Yes, I've seen choke and throttle cables glowing bright red before.........
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