MR 2 Ring gear

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Mon 3 Jul 2006 00:25
MR 2 Ring gear - Carl2
A work colleague has a 1991 MR 2 2litre GT (import). The car can be driven when bump started no problem. When turning the ignition key there is just a wirring sound . The starter motor turns over on a bench (not under load). He has said that the ring gear can be moved with finger tip pressure so I would like to know if this is a straight forward job with any possible short cuts . I have fitted starter ring gears on flywheels years ago and I am guessing it is still the same procedure? any advice with removing the gearbox or engine would be very much appreciated.
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Mon 3 Jul 2006 00:32
MR 2 Ring gear - Aprilia
So you mean the ring gear is loose on the flywheel? If so then I would get a s/hand flywheel. The old flywheel must be damaged by now if its had the ring gear spinning round on it.

Are you sure the starter pinion clutch is not slipping under load?
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Mon 3 Jul 2006 00:50
MR 2 Ring gear - Carl2
he told me he could move the ring gear just by putting his fingers through the starter motor hole so I assume there must be far less resistance than I would have expected. I would agree starter pinion would be a more likely suspect. I have never heard of a ring gear slipping (although I suppose someone must have had a gear crack at some time) . The only problem I,ve ever encountered has been damaged teeth . I shall ask him to make sure the gear is moving when pushed with finger tips. thank you.
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Mon 3 Jul 2006 08:53
MR 2 Ring gear - Collos25
We used to move the ring gear on MGB's because they use to wear very quickly it was one hell of a job ,I cannot for the life in me see one being loose unless it was damaged.If it was so loose it would throw itself of the flywheel and cause untold damage I would change the starter first or pinion if it is available as a seperate part.
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Mon 3 Jul 2006 09:23
MR 2 Ring gear - Peter D
It sounds as though the ring gear has cracked and let go of the flywheel. I have now seen that for many years. Fitting a new ring gear is always fun and a good change to burn you fingers when they come out of the oven at 140 degrees C. You will need two peopls and 6 preset welders clamps or G clamps. Remember you only have 15 seconds before it locks on. Regards Peter
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Mon 3 Jul 2006 09:46
MR 2 Ring gear - sierraman
Surely this isn't a Bendix type of starter?In which case I would think that the solenoid is not engaging the starter with the ring gear..Is your colleague(=person you work with) sure he isn't turning the flywheel as well?It is possible-if it was loose I don't see how it would stay on.
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Mon 3 Jul 2006 13:21
MR 2 Ring gear - Aprilia
Well, the only way could see it moving is if the gear has cracked - but then I would expect it to come off and cause all sorts of havoc. If you do indeed need a new ring gear then surely the old flywheel must be damaged where the ring gear has moved on it - a new ring gear probably wouldn't hold. Best bet is a complete s/hand assembly from a breaker.
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Mon 3 Jul 2006 23:20
MR 2 Ring gear - Carl2
I still haven,t seen the car yet so my imagination could be getting a bit carried away here but .Is it possible that there is a set of planet gears meshed to the flywheel and my work mate is turning these? if so would the pinion clutch be incorporated with these in a bolt on unit (really clutching at straws now)?
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Tue 4 Jul 2006 10:24
MR 2 Ring gear - Peter D
No. If there was then the flywheel doing 6000rmp would mean the planet gear being exactly that 'A Planet' doing 50,000 RPM. Regards Peter
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