[C2] Shims for starters ?

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Jun 3, 2025 | 08:52 PM

riggsjr

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Shims for starters ?

I took my starter out of my 66 today and noticed one very very slim shim.It did not look like it was doing anything. My question is is this shim doing anything. I went to a cruise night tonight to walk around and mentioned to someone and they said every car that came off the production line had a shim from the factory.I wonder if the person before me who restored the car put it in there for judging? Does anyone know?

Jun 3, 2025 | 09:02 PM

R66

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From: Really Central IL Illinois

I have taken apart more than 10 SBCs and only found a shim under 1 starter. I doubt GM would have spent the money to shim every starter.

Jun 3, 2025 | 10:10 PM

jim lockwood

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From: northern california

C2 of Year Finalist (track prepared) 2019

I've had to shim an aftermarket starter but never a stock Shev-a-lay starter. Further, unlike Ron, I've never disassembled an SBC and discovered a shim.

Jun 3, 2025 | 10:11 PM

Easy Rhino

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From: Middle TN by way of KY, OH, VA, IL, CA, FL, NY, SC, HI

Been decades so my memory is rather non-specific, but measuring for shimming starter installation was something we 'knew' to do back in the day.

Jun 3, 2025 | 10:20 PM

R66

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From: Really Central IL Illinois

I have had to use shims when I installed a new or rebuilt starter as the bendix gear stuck in the flywheel. If you found a shim and are going to reuse the starter you took off, I would use it for reinstallation. There are threads from the past on measuring the clearance using a paper clip.

Jun 3, 2025 | 11:02 PM

jforb

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From: Sierra Vista, AZ

Measuring using a 1/8" allen wrench (between outer edge of ring gear tooth and starter shaft, you want it to fit in, but not be able to twist it) is a common thing to have done with Chevy starters...if it's too tight, add full shims as needed, if it's too loose, ad half a shim at the outboard side as needed.

but I wasn't around long enough ago to know what Chevy did in the 60s with shims.

Jun 4, 2025 | 09:48 PM

John S 1961

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From: Scottsdale AZ

I have added shims when I replaced a starter and it was obviously grinding or not running smoothly and loud too. Added a shim and then nice and quiet and smooth. Depends on tolerances. Some are too tight some are just right.

Jun 5, 2025 | 07:14 AM

riggsjr

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Quote:

Originally Posted by John S 1961

Well the starter is back in. No shim at first. I thought I was hearing a scrapping noise after disengaging. I added the slim back and it sounds better. Thank you everyone for your responses.