Broken starter bolt

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smdk2500

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Truck is a 95 with the 5.7. I had starter problems that I thought that was just a bad starter that was not allowing the drive to extend into the flywheel. Come to find out I had a broken bolt and the other was loose. Long story short I got the broken off part out and replaced both bolts with new as well as replaced the starter due to breaking both studs off on the solenoid. My question what can be the cause of broken bolts? I'm guessing in my case they were loose and the starter torquing just finally broke one of them. I know on the 6.5 platform the cause of them is because people don't install the rear support on them and that is what causes the bolts/block to break. This is the first time I've had one break on a small block. My starter is the PMGR and does not that I know of use a rear support bracket. What else can cause this problem so that I hopefully have to worry about this again.
 

tpass

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Truck is a 95 with the 5.7. I had starter problems that I thought that was just a bad starter that was not allowing the drive to extend into the flywheel. Come to find out I had a broken bolt and the other was loose. Long story short I got the broken off part out and replaced both bolts with new as well as replaced the starter due to breaking both studs off on the solenoid. My question what can be the cause of broken bolts? I'm guessing in my case they were loose and the starter torquing just finally broke one of them. I know on the 6.5 platform the cause of them is because people don't install the rear support on them and that is what causes the bolts/block to break. This is the first time I've had one break on a small block. My starter is the PMGR and does not that I know of use a rear support bracket. What else can cause this problem so that I hopefully have to worry about this again.
you nailed it... loose bolts
 

Schurkey

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...or WRONG bolts.

The PMGR starters have a larger bolt hole for the shank of the bolt to go through. But the block is still 3/8-16. So the PMGR starter bolts are "special" in that the shank is bigger than the threads, with the knurl near the bottom having a "step" so it locates nicely in both the starter and in the block.

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AuroraGirl

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You must be registered for see images attach

...or WRONG bolts.

The PMGR starters have a larger bolt hole for the shank of the bolt to go through. But the block is still 3/8-16. So the PMGR starter bolts are "special" in that the shank is bigger than the threads, with the knurl near the bottom having a "step" so it locates nicely in both the starter and in the block.

You must be registered for see images attach
 
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