Author Topic: Shimming starter  (Read 16889 times)

Offline zieg85

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Re: Shimming starter
« Reply #15 on: January 23, 2012, 05:43:33 pm »

Cheers Zieg, I'm on it already!

Looks like I may have been a little under powered and it hasn't been chucking the bendix in far enough.

Could this explain why I could only see small shiny marks on the ring gear? Does it sound plausable?

I'm hoping that's the prob!

Cheers (and fingers crossed!)

Underpowered still should be slow to cranking.  Sounds like the starter may still have issues if the bendix is not engaging the ring gear.   I have had several rebuilt ones have issues right out of the box. 
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline Captkaos

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Re: Shimming starter
« Reply #16 on: January 23, 2012, 09:25:34 pm »
If it is engaging but not turning or turning very slow, I would say cranking amps.

Offline Irish_Alley

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Re: Shimming starter
« Reply #17 on: January 24, 2012, 09:29:35 am »
If it is engaging but not turning or turning very slow, I would say cranking amps.
this is what i thought the problem was from the first post
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Offline Bitzer!

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Re: Shimming starter
« Reply #18 on: January 24, 2012, 10:41:25 am »
Ok guys, this is what I'm looking at. It's an Exide 100Ah 850CCA - is there anything else I should check? Not worried about size etc as I'm relocating it anyway!!

That should do the job??

Off to search for that paper clip again, see if I can get it shimmed then the battery should be with me by the end of the week to see what happens.

If it's not the right battery please tell me asap before I order!!

cheers
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Offline Captkaos

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Re: Shimming starter
« Reply #19 on: January 24, 2012, 01:47:55 pm »
850CC is definitely enought battery.  You should be able to use a 650CC (CC= Cold Cranking)

Offline Irish_Alley

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Re: Shimming starter
« Reply #20 on: January 24, 2012, 03:03:29 pm »
how do you have the engine grounded?
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

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Offline Bitzer!

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Re: Shimming starter
« Reply #21 on: January 24, 2012, 03:38:45 pm »
Irish > I've been cheating! I temp wired it straight to the battery with no other electrics connected. I didn't want to fire it up until I knew it was shimmed properly.

Chris> I'm going on the side of too much rather than not enough!!

Ok, up date for tonight:

Found the paperclip! Borrowed a better battery with increased CCA. I finally got to 4x shims on the outer pad and it's nearly there.
The better battery throws the bendix right into the ring gear and meshes nicely. I think the previous battery only threw the cog in a few mm instead of fully across.

The only problem I've encountered now is the outer bolt has pulled the thread  >:( so I'll hunt for a longer bolt to reach the fresh thread or gently re-tap it to accept a bigger bolt.

On a positive note, I discovered a tapped hole in the corner that means I should be able to fit a hi-torque starter at a later date should I need to!
1979 GMC CrewCab  C20 1t
454 750 Holley,TH350, 14bolt diff fully floating
Why aren't there 8 days in a week!
A K5 rolling shell *new addition*