Crap. I broke the head off a bolt and I need help getting it out

[sixstringsteve]

While tightening down my steering arms to the torque spec recommended by the manufacturer (150 ft lbs), I snapped the head of a grade 8 bolt off inside the knuckle. The good news is that it's a through-hole, with about 1/8" of the bolt sticking out the bottom. The bad news is that it broke at around 130 ft/lbs, and I had blue loctite on it.

I've heard that summit machine can get broken bolts out. My question is, can they do this on the axle, on the vehicle, or do I need to remove the knuckle and bring just the knuckle in? It's such a pain to remove the knuckle that I'm hoping I can find someone who can extract it while it's in the axle, but that may be a long shot.

 

[mbryson]

Weld a nut on it? That should heat the loctite up pretty well?

 

[Rot Box]

Drill down the center (make sure it is smack dap in the middle) a ways and use an extractor. If the threads aren't galled it should come out without too much trouble. Heat the knuckle with a butane torch (doesn't need to be super hot) and the loc-tite will loose its hold.


Good luck!

 

[airmanwilliams]

I work at Summit Machine. Ill bet we can do it. I'll call Julene now and ask for you. We have a forklift and can lift the axle but knuckle would be easier. I'll ask for details.

 

[BlueWolfFab]

Steve the best way ive found is welding a nut to the bolt and backing it out with a wrench. Bolt extractors are garbage in my opinion.

Also, if you want, I have several of the studs that are made for high-steer arms, if you want those instead of bolts.

 

[BlueWolfFab]

In fact I had to do this to 3 bolts on my civic this weekend.

 

[mbryson]

....Also, if you want, I have several of the studs that are made for high-steer arms, if you want those instead of bolts.

I vote this!!!

 

[sixstringsteve]

Great suggestions in here thanks. I don't think enough of the threads are sticking out the bottom to get a nut on it, but i'll give it a go.

Also, if you want, I have several of the studs that are made for high-steer arms, if you want those instead of bolts.

I may have to take you up on this.

 

[mbryson]

Great suggestions in here thanks. I don't think enough of the threads are sticking out the bottom to get a nut on it, but i'll give it a go.




I may have to take you up on this.

Even if you can get a half thread or so on there and weld it (sounds like you'll be welding overhead?) that should give you enough heat to kill the locktite and let you turn the bolt out

 

[TRD270]

Great suggestions in here thanks. I don't think enough of the threads are sticking out the bottom to get a nut on it

I maybe wrong but I think they are suggesting welding the nut onto the broken side, and attempting to remove it. Essentially welding a new head onto the bolt.

 

[sixstringsteve]

Even if you can get a half thread or so on there and weld it (sounds like you'll be welding overhead?) that should give you enough heat to kill the locktite and let you turn the bolt out

I'll have to see, but I think it's broken off too deep inside. The bolt broke off below the shoulder.

The only threads sticking out are sticking out on the bottom, where it went all the way through the knuckle. I'll get more pics at lunch.

 

[BlueWolfFab]

True, I was talking about the broken side. You also don't need any threads to be sticking out at all. The bolt can even be broken past flush a bit (1/8" or so) and still be just fine.

 

[Unimog]

Even of the threads are broken off a little ways in, just put a washer over the hole that is slightly smaller than the hole, then the nut. If it is broken off more than ~1/8 inch down, then welding the nut on might not be a good idea.

 

[mbryson]

Even of the threads are broken off a little ways in, just put a washer over the hole that is slightly smaller than the hole, then the nut. If it is broken off more than ~1/8 inch down, then welding the nut on might not be a good idea.

A brass or copper washer would be ideal for that

 

[mbryson]

I'll have to see, but I think it's broken off too deep inside. The bolt broke off below the shoulder.

The only threads sticking out are sticking out on the bottom, where it went all the way through the knuckle. I'll get more pics at lunch.

So if it's 1/2" or so down, I'd try to weld to the protruding on the bottom and try to spin it out that way. Assuming all the material in the bolt hole is threaded.

 

[SLC97SR5]

Drill down the center (make sure it is smack dap in the middle) a ways and use an extractor. If the threads aren't galled it should come out without too much trouble. Heat the knuckle with a butane torch (doesn't need to be super hot) and the loc-tite will loose its hold.


Good luck!

This. I use a dab of valve grinding compound for extra bite.

http://www.irwin.com/uploads/produc...spline-screw-extractors-522532-series-800.jpg

 

[jeeper]

I vote EZ out, welding can easily cause damage to the threads in the housing.

Backwards drill bit may also work well..

Extractors are VERY effective when done right.

 

[sixstringsteve]

It'd be less work to keep pushing the bolt all the way through. There's more sticking out the bottom than the top. I wonder if I can weld a nut to the bottom of it.

I'll check on the bolt size. It's got a 3/4" bolt head.

 

[sixstringsteve]

Steve, what size bolt was it? By the torque, I'm guessing 9/16 to 5/8?

Why I ask is that 150ft/lbs will shear the head off Chinese grade 8 9/16-18 bolts (threaded in dry) often - even though that's below their max. I used to keep a similar chart with my torque wrench so that I didn't wreck stuff on the job site.

View attachment 101543

I'm guessing this is exactly what happened. I'm going to print this out and leave it with my torque wrench. Thank you!

Is there a way to ensure I'm not getting a chinese grade 8 bolt? or are all bolts chinese these days?

 

[bryson]

Welding a thin nut (like a jam nut) to the broken end is certainly your best bet. Trying to weld a nut to the exposed bottom of the bolt means you would be threading the broken portion all the way through the threads, likely effing them up in the process (bolts never break off clean...) With the head broken off, the torque value that it was at prior to breaking SHOULD'T matter, right? Now it's just threads in a through-hole (assuming there isn't an unthreaded portion of the bolt between the head and threads that was forced into the threaded hole) - just the friction of the threads themselves and your thread locker is all you're fighting to get it back out. Some heat to release the thread locker, and it should back out fairly easy.