Wrong size starter

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Jmclean85

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Hey everyone! I searched to try and find this specific issue but no luck. I had a mechanic get me a new starter. It’s a vortec starter. The starter installed and works, but there’s a space around it. I can see the flywheel. Is this not going to cause major issues?
Thanks
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TechNova

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You need to get the correct bolt. If you take the starter off and look at the bolt holes there will be a counterbore before the threads start. This is to allow the knurled part of the correct bolt to help center or locate the starter properly.
I am not sure about why you have the gap
 

Schurkey

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The gap is no real problem. The bellhousing is designed for a starter with a larger "nose cone" than the Permanent Magnet Gear Reduction (PMGR) "Vortec" starter you've got. I suppose you could blort a tube of RTV Silicone in there to plug the hole; or cut a strip of rubber and glue it in place to seal the gap. I wouldn't bother.

The moron who crammed the incorrect bolt in that starter needs to be "educated".

GM PMGR starters have 10mm bolt holes, but the block needs a 3/8-16 thread. 10mm is bigger than 3/8". Therefore, the starter bolts are "special", having a 10mm shank that tapers at the threaded end. The GM bolts are inexpensive, and they taper at the knurl, so the knurl fits snug in the starter AND in the block, just like they should. ARP makes similar bolts, but the knurl is sized to fit the block, not the starter.

ARP packaging, plus the Summit part number for the GM bolts
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Jmclean85

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The gap is no real problem. The bellhousing is designed for a starter with a larger "nose cone" than the Permanent Magnet Gear Reduction (PMGR) "Vortec" starter you've got. I suppose you could blort a tube of RTV Silicone in there to plug the hole; or cut a strip of rubber and glue it in place to seal the gap. I wouldn't bother.

The moron who crammed the incorrect bolt in that starter needs to be "educated".

GM PMGR starters have 10mm bolt holes, but the block needs a 3/8-16 thread. 10mm is bigger than 3/8". Therefore, the starter bolts are "special", having a 10mm shank that tapers at the threaded end. The GM bolts are inexpensive, and they taper at the knurl, so the knurl fits snug in the starter AND in the block, just like they should. ARP makes similar bolts, but the knurl is sized to fit the block, not the starter.

ARP packaging, plus the Summit part number for the GM bolts
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Thanks for the gm part number for the bolts!
I suppose I can fab up something to fill the gap. It makes me nervous that a rock or something will get in there and mess up the teeth on the flywheel.
 

TechNova

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I have a couple old cars with no cover under the convertor, no harm done.
 
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