Author Topic: Shimming starter  (Read 16898 times)

Offline Bitzer!

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Shimming starter
« on: January 15, 2012, 04:00:04 pm »

Hi guys, I did warn you there'd be loads of questions now it's going back together!!

This ones more of a check!

When shimming a 454 starter, both sides are shimmed the same??

Does anyone have a max distance (appx) they have shimmed to? would 10mm considered excessive?

Cheers

Andy
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*

Offline heavychevy91

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Re: Shimming starter
« Reply #1 on: January 15, 2012, 06:16:16 pm »
Hey bitzer i found this in the tech section from a while back,

http://forum.73-87chevytrucks.com/smforum/index.php/topic,20263.0.html

Hope that Helps!

Offline VileZambonie

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Re: Shimming starter
« Reply #2 on: January 15, 2012, 06:20:54 pm »
Those are about as much info as you should need. Are you saying you have a 10mm thick shim?
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Offline firefighter

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Re: Shimming starter
« Reply #3 on: January 15, 2012, 07:28:35 pm »
would 10mm considered excessive?

10 mm is equal to about .393 or a little over 3/8".
Yes, that would be extremely excessive!!

I just installed a new flexplate on my 454 and had to shim the starter .090 and that was the most I've ever had to shim a starter in my life.


Offline Bitzer!

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Re: Shimming starter
« Reply #4 on: January 16, 2012, 03:45:18 am »

Cheers all

Vile I plucked 10mm out the sky as 2mm is easy to guess at! I haven't properly offered it up yet, its just hanging on the bolts!

I found the thread in the tech bit ages ago but couldn't find it again for some reason.
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*

Offline Bitzer!

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Re: Shimming starter
« Reply #5 on: January 22, 2012, 03:46:53 pm »

Ok Guys (+gals)

I'm all shimmed out!

I got the proper shims and spent all day trying and still no result.

Followed the info in the tech section and now I'm stuck. I even resorted to one shim inside and try, one shim outside and try, both together and try and increased each side trying each time.

Fully charged battery and it sounds like it's struggling to turn it over no matter what I try.
Removed starter and bench tested it, fires fine, it's new.

Rechecked the power/ground, all good. As it's a new built engine, I dropped the plugs out to lose compression and it turn over fine by hand.

Wondering if there's only one 454 starter, excluding the high torque type, that fits or is there different ring gear the starter runs on i.e. choice of two? Different number of teeth etc?

I've checked the ring gear, no cracks or visible distortion.

Slightly losing my mind on the simplest of things - help............

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*

Offline Captkaos

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Re: Shimming starter
« Reply #6 on: January 22, 2012, 06:38:18 pm »
Can you turn the motor over easily with a wrench?  There is only one starter for the 454's.

Offline Bitzer!

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Re: Shimming starter
« Reply #7 on: January 23, 2012, 01:13:11 am »
Yup without the plugs in it turns over with a socket on the front end.
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*

Offline Irish_Alley

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Re: Shimming starter
« Reply #8 on: January 23, 2012, 04:18:33 am »
couple question. while i get my big head into this. one what was your old starter doing. and two why you shimming i thought shims where to make the correct contact area for the teeth. just thinking outload for all this but it seams like a ground problem. this is why your starter works fine on a bench test but under a load its slow
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Offline Bitzer!

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Re: Shimming starter
« Reply #9 on: January 23, 2012, 07:10:11 am »
Hi Irish, the old starter ended up worn out. Solenoid kept stickin so I junked it and got a new one.
Re ground, I've run several incl back to the battery.
Bit puzzled at the mo tbh
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*

Offline Captkaos

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Re: Shimming starter
« Reply #10 on: January 23, 2012, 10:44:32 am »
If it is dragging, is you battery putting out enough amps?

Offline Bitzer!

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Re: Shimming starter
« Reply #11 on: January 23, 2012, 02:52:32 pm »

That was really my last option, the cranking amps. Insufficient would not throw the bendix gear out quick/far enough to mesh with the ring gear?

Any idea of what I'm needing for cranking amps on the batt??
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*

Offline zieg85

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Re: Shimming starter
« Reply #12 on: January 23, 2012, 03:45:22 pm »
http://www.autobatteries.com/basics/selecting.asp  Is a good reference however in my 454 I run a 785 in it.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline zieg85

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Re: Shimming starter
« Reply #13 on: January 23, 2012, 03:54:49 pm »
Year   1985
Make   Chevrolet
Model   C20
Engine   7.4 Liters 454 CID V8
Description -
BCI Data Book   Optional
BCI Group Size   78
ODYSSEY MODEL   78-PC1500
Pulse (5-second) Hot Cranking Amps (PHCA)   1500
Cold Cranking Amps (CCA)   880
20Hr Nominal Capacity (Ah)   68
Reserve Capacity Minutes   135
Dimensions
L x W x H - Inches   10.85 x 6.99 x 7.12
Metric Dimensions
L x W x H - mm   275.6 x 177.5 x 180.8
Weight (lbs)   49.5
Weight (kg)   22.4

Is what mine calls for...
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline Bitzer!

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Re: Shimming starter
« Reply #14 on: January 23, 2012, 04:39:03 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!)
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*