Bendix Gear

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Rob Frankham
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Re: Bendix Gear

Post by Rob Frankham »

George Ryals wrote:I think the solenoid has a pull in winding(strong force) and a hold in winding(not so strong force). If the hold in winding is faulty (when hot) the slightest bump( partial firing of a cylinder)may cause the spring to retract the bendix.
Hate to point this out but the sloenoid contacts are on the same linkage so, if that happened, the starter would stop turning.

Rob
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Major Softie
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Joined: Tue Aug 03, 2010 1:46 pm

Re: Bendix Gear

Post by Major Softie »

Rob Frankham wrote:Hate to point this out but the sloenoid contacts are on the same linkage so, if that happened, the starter would stop turning.

Rob
Still trying to work out why you hate saying it. Good point though. :mrgreen:
MS - out
Bob Bennett
Posts: 223
Joined: Wed Aug 04, 2010 6:51 am
Location: NSW Australia

Re: Bendix Gear

Post by Bob Bennett »

G'day and thanks for all that input, I do'nt think that clutch part is the problem, stuck it in a vice and heated it with
gas torch and could'nt make it slip' .
So now my theroy is that there is too much play in the bendix,
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It's probably worse than it looks because the bendix extends further than in the photo. Then the ring gear looks
like this.
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So I got the Dremil out and did a bit of work(dentistry) to clean up the burrs on the teeth.
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Tomorow I will be ordering a new bendix and will be happy if it solves my problem.
Thanks for all of your ideas and info, any further also eagerly looked forward to.
Setting up these photos and posting this has taken me longer than pulling out the starter!!!!!
(new to Computers am I )
Regards, Bob
R80 RS
Rob Frankham
Posts: 1221
Joined: Thu Aug 26, 2010 2:11 pm
Location: Scotland UK, 20 miles from civilisation up a dead end road!
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Re: Bendix Gear

Post by Rob Frankham »

Bob,

Those teeth aren't brilliant but I've seen worse... If they're like that all round the ring gear, I think the problem is something else. Can't help with exactly what it is but I think it will turn out to be mechanical rather than electrical.

Rob
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Bob Bennett
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Location: NSW Australia

Re: Bendix Gear

Post by Bob Bennett »

That's about half of the damaged teeth, the rest of the ring gear is fine.
Regards, Bob
R80 RS
Garnet
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Location: Victoria BC Canada

Re: Bendix Gear

Post by Garnet »

Bob, when the starter spins, does it make a realy bad grinding noise? That would indicate that the bendix is not properly engaging the ring gear. If it just sounds like an electric motor turning there is something else happening (maybe).

Only half of the ring gear will show wear as the engine usulllay stops in two different spots, about half way up the compresion stroke on one or the other cylinders.
Garnet

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Bob Bennett
Posts: 223
Joined: Wed Aug 04, 2010 6:51 am
Location: NSW Australia

Re: Bendix Gear

Post by Bob Bennett »

Yes, Garnet, that noise was happening occasionly, but is not happening now so I think it's all related.
I believe that with the slop in the pinion end of the bendix it was'nt engaging yet still spinning without
making a loud grinding noise, even though the bendix was'nt engaged the solenoid contacts could close
due to the spring on the outside of the bendix. You can see this spring between the clutch thing and the
washer shaped bit that the solenoid lever drives.
Anyhow I have ordered a bendix and it should be here tomorrow, will post the results.
Regards, Bob
R80 RS
Garnet
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Re: Bendix Gear

Post by Garnet »

Yes I think you are on the right track. ;)

While you are in there pay close attention to the bushings. I takes very little play in them, especsialy the nose cone one to cause trouble. They should be available from any starter/altenator rebuilder.
Garnet

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wirewrkr
Posts: 96
Joined: Mon Sep 27, 2010 6:54 pm

Re: Bendix Gear

Post by wirewrkr »

Garnet wrote:Yes I think you are on the right track. ;)

While you are in there pay close attention to the bushings. I takes very little play in them, especsialy the nose cone one to cause trouble. They should be available from any starter/altenator rebuilder.

They're only a few bucks each from BMW.
Buy the right ones the first time.
get all 4, not just the bendix bushings.
Bob Bennett
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Location: NSW Australia

Re: Bendix Gear

Post by Bob Bennett »

The S/Motor bushes seem fine, don't know anything about bendix bushes?
Regards, Bob
R80 RS
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