# Starter Shims



## timmyg (Jan 2, 2012)

Does anyone know if there is a way of determining prior to mounting a new Starter Motor, if the Starter Motor needs to be shimmed or not. I didn't know if there is a measurement or something similar that could be checked prior to installation. I am installing a new T.C.I. High Torque Starter on the 455 Engine I am rebuilding. When I took the motor out of the car and unbolted the old original starter, there were numerous starter shims being used, equaling between 3/16 and 1/4 inch. I am trying to determine whether or not it is "a given" that these same shims would need to be re installed. I am trying to determine prior to assembly as the shims would be easier to install now versus once the engine is back in the car. When I measured the thickness of both the old and the new Starters Mounting Surfaces where the two mounting bolts run through, both Starters measured 3 5/8" thick. I have never myself had to use shims with a starter but I know it is common to have to use them sometimes. This is why I am unfamiliar with what really determines whether or not they are needed. Any help appreciated.


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## geeteeohguy (Feb 2, 2008)

If the measurements are the same between starters, and the previous starter worked well without grinding or noise, by all means re-install the shims. You could power up the bendix or extend it with the engine still on the stand to check the clearance. If undershimmed, you could shap teeth off of the flywheel ring gear. Same with over-shimming, though too many shims tend to chew the teeth up. A sure sign of too few shims is a grinding or whining sound when cranking the engine. There should be no starter noise.


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## BearGFR (Aug 25, 2008)

:agree If you hear sort of a "shrieking" sound just as the engine catches and the starter disengages, it's too tight and needs to be shimmed. Add shims a little at a time until the shrieking goes away.

Bear


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## pontiac (Mar 6, 2011)

mount starter to block, extend bendix and check clearance with paper clip wire. too tight, add shims so paper clip wire has clearance.


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## EP Goat (Dec 18, 2008)

*From 400 to 428*

Should the starter be able to handle a 69-428? it was fine with the 69-400. we have added about 8 shims so far.


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## fasterfiero (Sep 6, 2011)

:agree check with paper clip , my last starter came with a piece ow wire to check the clearance, Clarence....


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## BearGFR (Aug 25, 2008)

8 shims are a lot...something doesn't sound right there. I agree with the paper clip test. Drop the cover off the bottom of the converter, take a screwdriver or other tool and pry the starter pinion gear out so that it's engaged with the flywheel/flex plate. When it's "right" you'll be able to insert a paper-clip wire into the gap between the sides of the gear teeth, but only just.

Bear


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## geeteeohguy (Feb 2, 2008)

8 shims are indeed a bit much, but I've seen that many shims more than once, with no issues....go figure.


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