Sinners Saint
New Member
Anyone else ever had this happen? The outside starter bolt sheared off in the block and I had to remove it. Just want to see if its a normal occurance.
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Sheared off starter bolt
- Thread starter Sinners Saint
- Start date
Mudbath
Old Smoky
:iagree:
SmithvilleD
Active Member
BK, any chance you have a set of these bolts off & handy to measure?
I'm curious is they happen to be the same dimensions as any of the off-the-shelf ARP starter bolt sets for Chevy? The 2 bolt kits run $12-13, so if one of these std cat #'s are the right bolts, they'd probably be a good peace of mind upgrade.
I attached a .pdf of the relevant page in ARP's catalog. Wouldn't think they'd mind as it's publically available on the net.
Matt Bachand
Depends on the 6.5
You never know if they designed the bolt to break at a strength less than the block. Meaning I'd rather have a broken bolt than a broken block.
I'll stick to OEM bolts here.
I'll stick to OEM bolts here.
Dan Hunter
Truck Terrorist
I agree. Having snapped on, I'm checking them on oil changes and replacing them with batteries.
SmithvilleD
Active Member
Has anyone had a failure breaking a chunk of block off w/ the rear support bracket still tightly fastened?
Reason I ask is it seems unlikely that type of block failure would happen without starter weight allowed to act as a lever arm on the block.
Could see starter bolts possibly failing either by that lever arm stress, or possibly over torquing & then a failure starting at/near the knurling/stress riser.
Could even see bolt fatigue building, but not to the point of failure at the point in time somebody figured out to put the rear brace back on. Then daily vibration causes the weakened bolt to fail later.
Not trying to be argumentative, just working to understand the true cause of these not uncommon failures.
Reason I ask is it seems unlikely that type of block failure would happen without starter weight allowed to act as a lever arm on the block.
Could see starter bolts possibly failing either by that lever arm stress, or possibly over torquing & then a failure starting at/near the knurling/stress riser.
Could even see bolt fatigue building, but not to the point of failure at the point in time somebody figured out to put the rear brace back on. Then daily vibration causes the weakened bolt to fail later.
Not trying to be argumentative, just working to understand the true cause of these not uncommon failures.
BigBlueChevy
Compression Ignition Addict
starter bolt size is: M8 x 1.25 x 18
IIRC, someone had posted either here or "over there" on a nice 599 block they had gotten ahold of, but the block had a healthy chunk ripped out of it from where the starter sheared off.
I think I got lucky with mine. I had been going for a few months without that bolt when I finally realized what the rattling noise was(heat shield for starter was bouncing around during idle) I picked up a bolt from Sears of the same specs and popped it right in.
IIRC, someone had posted either here or "over there" on a nice 599 block they had gotten ahold of, but the block had a healthy chunk ripped out of it from where the starter sheared off.
I think I got lucky with mine. I had been going for a few months without that bolt when I finally realized what the rattling noise was(heat shield for starter was bouncing around during idle) I picked up a bolt from Sears of the same specs and popped it right in.
Matt Bachand
Depends on the 6.5
I am still running the bolts that came with my truck 4 years ago. 2 years of that were running without the starter brace.
Now with the brace and Factory bolts I don't worry.
Now with the brace and Factory bolts I don't worry.
SmithvilleD
Active Member
I understand the M8 diameter & 1.25 threadpitch, but are you sure on the 18? What unit's? Maybe 8 cm?, although that seems shorter than I recall the bolts being.
BigBlueChevy
Compression Ignition Addict
I'll second that one. Feels good knowing there is something in there reinforcing the starter. That and the stupid heat shield banging around at idle.
midniteplowboyy
Recruit
Thats the bolt for the brace to the block. "18" means 18mm long.
The two actual starter bolts should be 10mm, not 3/8" like the older gassers.
ARP would be a good choice, if not get factory GM bolts.
94K30
Diesel nut
That size sounds like the starter bracket to block bolt, not the starter bolts....
midniteplowboyy
Recruit
Keep an eye on that brace, they break in half sometimes.
94K30
Diesel nut
you type faster, Midnite....
I'm pretty shure the starter bolts are m10x1.5x?They have to be over100mmin length. I can measure in the morning. I already have my shoes off. I have had 2 of the braces break in half. They are wimpy. This is the one I made for my 93 to clear the frost plug heater on the passenger side. It's 1x1x1/4 angle iron.
Attachments
The starter bolts are m10x1.5x11.5mm. I believe failure with bracket installed could be caused by fatigue in the bolts. Both from tightening and stress from the starter pulling on them. A stud with full engaugement in the threads would be better but it would need to have the knurling on it and a socket end like the head studs have for removal. A flange mount would have been a much better design.