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Discussion Starter · #1 · (Edited)
Need advice on broken bolt

Long story made short, one of the holes in the frame where the lower crossmember (supports lower two motor mounts) bolts up is pretty well ruined (threads missing on one side, small pieces of old bolt stuck on other side). I do not have the tools to do so, but it is possible to completely drill the old "hole" out and put some sort of an insert in so I can put the bolt back in to hold the crossmember? If so, what exactly do I need to do (process-wise) to accomplish this, and who would be best to take it to? (mechanic, metal shop, etc.) Keep in mind, I cannot pull the frame piece out of the car to work on, so it would have to be somewhere where they have a lift for the car, or wouldn't mind working on it on jackstands.

Help!
 

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Discussion Starter · #2 · (Edited)
I know its a friday, and many people are not in a technical mood, but not even 1 view?? Would something like a Helicoil work? I have seen both good and bad reviews of their inserts, but not sure if it would work since part of the original hole is missing (picture the cylinder that the bolt goes into with about 1/4 - 1/3 of the thread wall gone.
 

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MN01GXE said:
Long story made short, one of the holes in the frame where the lower crossmember (supports lower two motor mounts) bolts up is pretty well ruined (threads missing on one side, small pieces of old bolt stuck on other side). I do not have the tools to do so, but it is possible to completely drill the old "hole" out and put some sort of an insert in so I can put the bolt back in to hold the crossmember? If so, what exactly do I need to do (process-wise) to accomplish this, and who would be best to take it to? (mechanic, metal shop, etc.) Keep in mind, I cannot pull the frame piece out of the car to work on, so it would have to be somewhere where they have a lift for the car, or wouldn't mind working on it on jackstands.

Help!
What you are referring to is helicoil. I've used them, and they are ok fixes. Best bet would be to drill it clean and retap it slightly larger, and replace the bolt with one of a larger corresponding size.

Not sure if helicoils come in that size, but you could check. I'm just not a huge fan of helicoil.
 

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Discussion Starter · #4 ·
Joe M said:
What you are referring to is helicoil. I've used them, and they are ok fixes. Best bet would be to drill it clean and retap it slightly larger, and replace the bolt with one of a larger corresponding size.

Not sure if helicoils come in that size, but you could check. I'm just not a huge fan of helicoil.
Thanks for the advice, but here is what I have noticed so far...

That bolt is near impossible to track down in a hardware store (has non threaded end, threads about an inch and a half up, then a solid metal cylinder wider than the threaded portion up to the head), so not sure if I could find one the next size??

It appears like the original tube that the bolts fastens in to was just that - a tube. In a poor attempt at drilling out the broken bolt, the drill bit went off center and appears to have taken out part of the threaded tube wall all together, leaving an open view in to the inside of the frame (as in its hollow, not solid with the holes drilled into it for the bolts). Is it possible that this tube could be replaced with another, welded into the frame rail for the bolt to fasten in to?
 

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MN01GXE said:
Thanks for the advice, but here is what I have noticed so far...

That bolt is near impossible to track down in a hardware store (has non threaded end, threads about an inch and a half up, then a solid metal cylinder wider than the threaded portion up to the head), so not sure if I could find one the next size??

It appears like the original tube that the bolts fastens in to was just that - a tube. In a poor attempt at drilling out the broken bolt, the drill bit went off center and appears to have taken out part of the threaded tube wall all together, leaving an open view in to the inside of the frame (as in its hollow, not solid with the holes drilled into it for the bolts). Is it possible that this tube could be replaced with another, welded into the frame rail for the bolt to fasten in to?
Well, you could try bolting it up with a nut/bolt combo. Not sure what the frame rail looks like on the inside, i.e. don't know if you can fit a nut into the rail.
 

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Discussion Starter · #6 ·
Joe M said:
Well, you could try bolting it up with a nut/bolt combo. Not sure what the frame rail looks like on the inside, i.e. don't know if you can fit a nut into the rail.
Not sure, I guess I will have to look at it further...afaik, it was a sealed scare tube running from left to right (radiator, condensor, etc. sits on it), but that might be something to look in to.
 

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Discussion Starter · #7 ·
Bump for some of the machine shop gurus to help a fellow member in need!!
 

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Discussion Starter · #8 ·
UPDATE:

Pictures will have to follow when get around to them, but basically, here is what I had to do:

- take a cutting wheel and cut a slot in the front of the support bar that the lower crossmember bolts in to (supports bottom of radiator).
- pry off remains of bolt and nut that is welded inside the support bar.
- weld on new nut inside of support bar.
- weld patch onto front of support bar to cover new hole.
- bolt crossmember back in after a dozen or so hits with a BFH to straighten out the slight curves the crossmember had gathered from two months of only being supported by three bolts.
 
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