Author Topic: Odd intermittent starter noise  (Read 846 times)

revilla

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Re: Odd intermittent starter noise
« Reply #30 on: 01 May 2020, 10:33 AM »
Sorry for the confusion Daniel. I should have been more clear. In my tips above, the full assy in your 1st picture should be standing on the bench/vise with the gear on top. Then you will turn (it’s helicoidal on the inside) and push downwards the gear (not the clutch disc) to reveal the groove/clip.  Or, you could turn the full assy upside-down and see if you have a clip on the opposite tip of the main shaft (far from the gear tip). So, if easier, you could then slide out the core/winding unit out and after the clutch/bendix assy.

Good luck. Keep up posted please.

 
Robert
W116 1977 280SEL & 1979 280SE

daantjie

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Re: Odd intermittent starter noise
« Reply #31 on: 01 May 2020, 11:06 AM »
OK here is what I see, the "top" is where the little chrome cap is (where my finger is pointing), how will you get the teeth/cog to drop down here, tap with a socket?  Might break the teeth then?  Does the c clip sit under this cap?  Then second pic, this is the opposite end, there is only a large c lip which sat underneath the "grease cap", it sat in the groove visible and it dropped out when I took the grease cap off, I can see no other way to remove the shaft from this end, it appears a unit.  Still confused :-\

Daniel
1977 450 SEL 6.9 - Astralsilber

revilla

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Re: Odd intermittent starter noise
« Reply #32 on: 01 May 2020, 11:19 AM »
I see. Is that ‘chrome cap’ machined on the shaft? Or is it really a cap? If it’s a cap, it means it can be removed. It will deform but you can get it back in shape securely during re-assembly. Obviously the gear won’t be able to pass that cap. But if removed, it should. By memory there should still be a C clip under the cap that retains the gear on the shaft.

I seem to remember there are actually 2 Bosch part numbers for the 6.9. Perhaps they changed the retaining design from C clip to Cap (don’t know). Nobody has done this job before?
« Last Edit: 01 May 2020, 11:24 AM by revilla »
Robert
W116 1977 280SEL & 1979 280SE

daantjie

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Re: Odd intermittent starter noise
« Reply #33 on: 01 May 2020, 11:40 AM »
The cap is loose for sure, not machined on.  I am highly doubtful that there can be a c clip under this cap though?
Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

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Re: Odd intermittent starter noise
« Reply #34 on: 01 May 2020, 11:50 AM »
Finally success!  That cap is just a dust cap.  No c clip.
I just pulled and turned in the end and then the unit comes off the shaft, not sure why it did not happen before, quite odd...
Daniel
1977 450 SEL 6.9 - Astralsilber

revilla

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Re: Odd intermittent starter noise
« Reply #35 on: 01 May 2020, 11:59 AM »
 :)

Did you check the old gear was wobbling on the shaft?
Brass insert present? Worn?
Clutch turning in one direction only?
That’s important because it’ll confirm your failure mode (motot/shaft turning but not the gear). If you venture, you can apply 12V to the selenoide while securely holding the gear to see if the clutch works. My theory is that it works 1/5 and worse on cold weather like it used to happen to me.
You’re almost there Daniel!
Robert
W116 1977 280SEL & 1979 280SE

daantjie

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Re: Odd intermittent starter noise
« Reply #36 on: 01 May 2020, 12:24 PM »
Thanks a lot for your help!  Not sure what you mean by brass insert?
I could not detect much of any wobble.  But...my new spare bendix does not appear to want to go onto the shaft, even sans the small ball bearings, what the heck?  I guess I need to buy a MB unit and cut to the chase on this bendix saga.

OK scratch that, seems like it just has a lot tighter clearance than the old one, I guess a sure sign that the old one is done for.
« Last Edit: 01 May 2020, 12:56 PM by daantjie »
Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

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Re: Odd intermittent starter noise
« Reply #37 on: 01 May 2020, 03:52 PM »
Okie dokie, I got the old bendix out and the new one in.  "Ja well, no fine" as we say in South Africa.

But now the solenoid is fighting me, argh this bloody starter will be the end of me! 

I am really not sure how the solenoid works to be honest, but what I see is the "fork" sticking out, visible in the solenoid housing.  Ok great, but how does the pin/spring of the solenoid actually move the fork?  And does the spring "face" of the solenoid pin have to face a certain way?

I am having trouble getting the solenoid back in so I think it is getting jammed up somehow?

Also, the fork is not under tension, which is odd, no?  What I mean is I can manually make the bendix move out by pulling the fork, but it does not snap back under tension, huh?

Oh man I'm lost, now I see why auto electricians ask an arm and a leg and why I have always stuck my head in the sand with electrical, "no mas" I tell ya!

Any sage advise appreciated ;D
Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

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Re: Odd intermittent starter noise
« Reply #38 on: 01 May 2020, 04:56 PM »
OK, I'm down but not out ;D  The champ is here!  OK maybe not...

I figured out that you have to hook the fork onto the solenoid pin, DUH!  Man I'm thick lately, let's blame Covid - brain.

Bench tested it, yay it works!  But...even though it throws out very crisp, it does not always wind all the way back in, I guess this is a problem..?  I fired it about 10 times, and half the time it was about 2 - 3mm from flush.  What gives :-\
Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

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Re: Odd intermittent starter noise
« Reply #39 on: 02 May 2020, 02:56 PM »
I took the starter to a local auto - electrical outfit for them to bench test.  They said it's A - OK, and apparently as the bendix is new it might be a bit tardy to spin back completely into the housing on the bench as the tolerances are now tighter, however once the engine spins it out after firing it should rapidly return to the housing.  Sounds plausible and I'm inclined to defer to the experts on this one.  So far so good...
Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

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Re: Odd intermittent starter noise
« Reply #40 on: 06 May 2020, 01:01 PM »
It's alive ;D!  Dropped the starter back in today and she fired up like a champ, first try, yay!

Thanks to all for all the encouragement and tips.  If any other 6.9 owner needs some tips on the intricacies of this Bendix I can share.  It is a bit tricky to swap out because of the ball bearing arrangement.  I knew I stumbled on a good shop for the bench test when the first words out of the guy's mouth were:"This is the one with the little ball bearings, are you sure you got them all back?!" ;D

Cheers
Daniel
1977 450 SEL 6.9 - Astralsilber