Snapped compensator bolt
Grand HDF Member
Joined: Nov 2012
Posts: 4,994
Likes: 2,081
From: Newport,TN area
Agreed - EDM is the path forward, however, it means you are
removing the motor and disassembling as much as you can
to take it to the EDM shop...
FWIW I had a shop with an EDM machine remove a small bolt
that had snapped off in a throttle body (car application) and it worked great.
good luck,
T.
removing the motor and disassembling as much as you can
to take it to the EDM shop...
FWIW I had a shop with an EDM machine remove a small bolt
that had snapped off in a throttle body (car application) and it worked great.
good luck,
T.
Stellar HDF Member
Joined: Sep 2021
Posts: 2,014
Likes: 1,467
From: Black Hills of SD
Our machine shop would have been able to do it as it sits - But that was one of the largest Aerospace corps. We had the guys who did everything and anything. As an engineer, we did a lot of very custom work and required the guys to be able to support us. I figured many larger machine shops would also be able to do he same - But I may be wrong. I have never had to deal with machine shops other than at work.
Worth a shot to call around and see what people tell you. EDM would be the fix, getting the EDM work done may be tougher from what some of the guys are saying.
Worth a shot to call around and see what people tell you. EDM would be the fix, getting the EDM work done may be tougher from what some of the guys are saying.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,894
Likes: 8,002
From: poway
Our machine shop would have been able to do it as it sits - But that was one of the largest Aerospace corps. We had the guys who did everything and anything. As an engineer, we did a lot of very custom work and required the guys to be able to support us. I figured many larger machine shops would also be able to do he same - But I may be wrong. I have never had to deal with machine shops other than at work.
Worth a shot to call around and see what people tell you. EDM would be the fix, getting the EDM work done may be tougher from what some of the guys are saying.
Worth a shot to call around and see what people tell you. EDM would be the fix, getting the EDM work done may be tougher from what some of the guys are saying.
So wouldn't you have to turn the crank sideways and flood the area, then use some precision placement device for the tool to perform the cut. Seems to me that a good cobalt drill and a drill bushing would be a lot easier. Don't have to disassemble the motor.. Technically the only thing holding the busted bolt in place is red locktite.
Grand HDF Member
Joined: Nov 2012
Posts: 4,994
Likes: 2,081
From: Newport,TN area
enough heat to have any effect on the locktite since only the end of the coil
would touch the area ?
thanks,
T.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,894
Likes: 8,002
From: poway
An induction heater coil is designed to heat metal is inside the coil. Shove a small coil down the hole would likely heat what is outside the coil and maybe a little on the end.. It would be easier to use an induction oil on the shaft and heat it.
Seasoned HDF Member
Joined: Sep 2008
Posts: 14,143
Likes: 11,214
From: San Diego, CA
I use an induction heater on comp bolts. I use the Bolt Buster induction heater. I've had it for years. Luckily got it before the price went way up.
I put a coil around the head of the comp bolt. I use it on both the older types with a standard hex head and the newer types with the 70mm hex head. It works great, as I only give it about a 5 second shot, and the comp bolts come off with little effort on my 24" breaker bar.
However, as Max said, the coil would need to surround the outside of the bolt head to heat it. The heat is generated inside the coil, not outside. If the bolt head is missing, I don't think it would work.
Last edited by hattitude; Oct 20, 2025 at 08:36 AM.
Cruiser
Joined: Feb 2024
Posts: 155
Likes: 134
From: Na Hampsha/Upstate SC
I have no words....
Among a certain circle of friends, I'm known as Dr. Torque, but this, wow. OP still hasn't given details on just HOW this happened. Prior to the >SNAP<, there must have been signs. A certain lack of knowledge in this type of repair must be assumed, given the ubiquitousness of RED.
Keep us informed, OP. Good luck.
Among a certain circle of friends, I'm known as Dr. Torque, but this, wow. OP still hasn't given details on just HOW this happened. Prior to the >SNAP<, there must have been signs. A certain lack of knowledge in this type of repair must be assumed, given the ubiquitousness of RED.
Keep us informed, OP. Good luck.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,894
Likes: 8,002
From: poway
I use an induction heater on comp bolts. I use the Bolt Buster induction heater. I've had it for years. Luckily got it before the price went way up.
I put a coil around the head of the comp bolt. I use it on both the older types with a standard hex head and the newer types with the 70mm hex head. It works great, as I only give it about a 5 second shot, and the comp bolts come off with little effort on my 24" breaker bar.
However, as Max said, the coil would need to surround the outside of the bolt head to heat it. The heat is generated inside the coil, not outside. If the bolt head is missing, I don't think it would work.
I put a coil around the head of the comp bolt. I use it on both the older types with a standard hex head and the newer types with the 70mm hex head. It works great, as I only give it about a 5 second shot, and the comp bolts come off with little effort on my 24" breaker bar.
However, as Max said, the coil would need to surround the outside of the bolt head to heat it. The heat is generated inside the coil, not outside. If the bolt head is missing, I don't think it would work.
BTW, it's not 70mm, It's #70 Torx.
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Seasoned HDF Member
Joined: Dec 2005
Posts: 19,894
Likes: 8,002
From: poway
The minor diameter of a 9/16-12 bolt is 0.4663" Probably best to use the 3/8 Rigid extractor as the remnants would be about 0.046 thick.
Last edited by Max Headflow; Oct 20, 2025 at 09:14 AM. Reason: remnants
Seasoned HDF Member
Joined: Sep 2008
Posts: 14,143
Likes: 11,214
From: San Diego, CA
One thing I'd be concerned about when doing this is bolt reuse. I'd assume that you don't reuse the old bolt.. I reuse them a couple times then toss.. I might be the next guy to snap one off tho. Heck, on new ones I wire wheel off the locktite patch and only TQ to 150 FP with the red. IMO the ridiculous torque HD spec'ed and the tighten to 100 back off and re-torque is due to the patch.. I suspect the reason for that process was to fix production issues. The patched bolts need to squeeze out all the patch between the internal/external threads on the tension side of the mate.
BTW, it's not 70mm, It's #70 Torx.
BTW, it's not 70mm, It's #70 Torx.
Yeah, I know it's a 70 Torx, I have no idea why I typed 70mm...
I do replace the comp bolts each time.
But IIRC, the earlier Factory Manuals say it's OK to clean and re-use the bolt with red locktite.
Are you saying that the heat applied could cause the issue, or the OEM toque spec is what requires the use of a new bolt... ?