I have an '89 IROC with the stock 350 TPI and automatic trans. My original starter died, so I pulled out one of the LT1 starters I have and figured I was in for an easy switch. I ended up trying both the standard size '94 LT1 starter and also the smaller and more powerful '97 LT4 version. I mounted them directly to the block, and also used a shim kit, trying nearly every combination from 1/32" to the full stack of them.

I get the exact same result every time, it spins out and clicks but cant turn the engine. Yet I can turn the engine over freely by hand. The starter gear is always stuck on the flywheel when I get under there to try another shim. Anyone ever have this problem? These are starters that worked flawlessly for me on other small blocks, and I had zero problem starting this IROC until I blew a head gasket, at which point the starter decided to quit at the same time.

Any suggestions? Anyone else have such an issue? Ive never even needed to shim a starter before, no idea why this would be such an issue.

 

Use the paper clip method to determine the backlash needed. More or less, theres only one set amount of backlash that will work. The others will cause poor operation of the starter.

Also check to be sure you have good power and ground connections, as well as the correct wiring at the starter.

 

Use the proper length bolts for your starters an ditch the nut. The bolts are shouldered to keep the starter straight.
It may just b the picture but it "looks" like the starter gear is cocked compared to the flexplate.

 

Yes I noticed that too once I saw the full sized picture. I actually picked up some more starter bolts yesterday. The nut corrected the difference in lengths between the starter bolts so that the dowel portion remained exposed, but its possible the shimming had taken up too much of it by the time that picture was taken.

I'll test out the new bolts and check with the paperclip tonight and give my results tomorrow. Thanks guys.

 

As mentioned, the starter bolts are specifically designed to accurately locate the starter. Thats important.

Hopefully that's all it is! LT1 starters are awesome.

 

Well a quick update, I definitely remember now why I used to use those nuts as bolt spacers on my LT1... the bolts these 97 LT1 starters need are seemingly unobtainable. Summit, ARP, local auto parts store, internet searches - everything results in a bolt length of either 3.7" or 4.5" but these starters require ~4". They dont seem to be available anywhere.

I never had a problem running the nut as a spacer before, but obviously since it is having some sort of alignment issue, I was all for using the correct bolts to eliminate possible problems. Every thread I've found in the last half hour ends with the person giving up having never found them.


According to Sallee Chevy, here are some possibilities. I'm headed to the dealership to see if any are correct, as searches return conflicting lengths
STARTER BOLTS

14097278 - Starter Bolt Long, special shoulder bolt, 3/8-16 x 4 21/64”.
14097279 - Starter Bolt Short, special shoulder bolt, 3/8-16 x 1 27/32”.
14037733 - Starter Bolt for 97 Camaro starter (P/N 10465293).

 

Here is the latest. Any GM bolt that would be the exact size for these starters is unavailable. I had a friend try from work at a dealership but we'll see if and when they arrive. In the meantime I used a digital caliper and some grade 8 washers to get the bolt extension exactly the same as stock, and it clearly gets aligned by the bolt knurl as I tighten them down.

It still gets stuck. I measured with the paperclip and it appears to have plenty of room. I also tried the earlier style LT1 starter that uses the stock bolts with no washers, and it also gets stuck. I was going to try another ministarter but it turns out to be for a 168 tooth flexplate, so it wouldnt work. Im now completely out of options.

Here is video of the starter getting stuck...I turn the key at the 1:10 mark:
http://youtu.be/LhhXp68r0fE

Here is everything Ive tried:

 

Another update on the bolts:
14037733 appears to be the correct short bolt for these starters

The other 2 part numbers (14097278, 14097279) are for the regular length bolts you can pick up anywhere, so I still need a part number for the long bolt that works on 95-97 starters. ????

Thanks

 

Here are the shorter bolt part #'s for using the later model PG260 starter in place of the early model PG250:
12338064 BOLT. Starter Motor. BOLT,STRTR(INBOARD HOLE)(3/8-16X4.33).

14037733 BOLT. Starter Motor BOLT,STRTR(OUTBOARD HOLE)(3/8-16 X 1.33)