Strange starter issue - UPDATE: Ring gear detached from fly

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chips
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Sat Jun 26, 2010 6:36 pm

I have a strange problem with my M42. The starter turns, but the engine does not. I can also hear the solenoid engaging (or trying to engage) but the engine won't turn.

I have tried two starters on it, the same thing happens with both.

If anyone has any clue what might be happening then I'd be grateful. I really need to get this car sorted. :-x
Last edited by chips on Mon Jun 28, 2010 10:00 pm, edited 1 time in total.
daimlerman
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Sat Jun 26, 2010 6:44 pm

Engine earth present and good?
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chips
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Sat Jun 26, 2010 8:00 pm

I just installed the engine about 3 weeks ago and used a new earth strap. Everything was working fine until I put the bonnet on, ready to take it for an MOT. Sods law I suppose.

It sounds like the starter isn't properly engaging the ring gear. Could there b any electrical issues that would cause this?
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ProToZyKo
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Sat Jun 26, 2010 8:21 pm

Im no expert at this but have you tried turning the flywheel by hand? maybe it's stuck? Is it properly mounted?
I have experience a few starter failures and it sounds like it's dead, but you have tried 2. Hit it with a hammer ;) always works.
chips
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Sat Jun 26, 2010 8:31 pm

i've tried rocking the car in gear and it all moved, engine has compression etc so nothing majorly serious.

I'm hoping theres no way the ring gear could have become detached from the flywheel? I didn't look at it too hard when it was out for lightening.
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Brianmoooore
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Sat Jun 26, 2010 8:46 pm

All locating pins and dowels in place?
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Brianmoooore
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Sat Jun 26, 2010 8:50 pm

All locating pins and dowels in place?
chips
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Sat Jun 26, 2010 9:02 pm

Brianmoooore wrote:All locating pins and dowels in place?
For the starter or the ring gear?
daimlerman
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Sat Jun 26, 2010 9:21 pm

Correct starter?
There are at least two pitches for the ring gear....
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chips
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Sat Jun 26, 2010 9:36 pm

One starter was the one that came with the engine and was working fine for a couple of weeks, starting it without any issues. The other is off my spares engine.
town325i
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Sat Jun 26, 2010 10:46 pm

You need to be carfull with this as in the end it can smash the teeth off the ring gear i had this trouble on an m40 engine but sold it before i got to the bottom of it and i used an m50 starter on it the last time and this would only miss the flywheel now and again
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chips
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Sun Jun 27, 2010 1:49 pm

It sounds like it could be the battery then. It was new around 3 weeks ago but I've been using it for cranking while I was getting the engine running and it's never had a charge that whole time.

I'll try jumping it and see if that helps.
chips
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Mon Jun 28, 2010 9:59 pm

Update:

I got a chance to grab half an hour in the garage tonight, so I thought I would try swapping the starter again. When I took it off, the ring gear just fell off the flywheel.

I can only assume that the company that lightened it have machined away whatever holds the ring gear in place. Brian, you mentioned dowels?

I have a spare flywheel on my spare engine, so now I have to pull the engine out again and swap the flywheel :( . I don't have any way to get the car high enough off the ground to remove the gearbox on its own.

I dread to think what would have happened if it had come off at speed on the motorway.
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