Broken Body Mount Bolt

[muckymotor]

I broke the #3 (just in front of the rear tire) driver-side body mount bolt while trying to remove it (thank you New England rust).

The issue is that the bolt is broken so far internally that it's impossible to weld anything onto it or grab onto it with vise grips. I've drilled a good-sized hole into the bolt, but I've yet find an extractor that's long enough to even reach the bolt. Here's a picture for reference:

I've seen a few people saying that body mount is impossible to access from above? Or if you ARE able to access it, you wouldn't have enough room to do anything to it. Is this true?

I don't love the idea of drilling the bolt out and ruining the threads and having to tap them.

Any suggestions? Tips? Tricks?

 

[thedustyboot]

I know they do sell those torque boxes to replace what you have IF they're corroded. That same body mount on my jeep is so far gone that it's really just there for show

What I've done in the past with similar situations of a bolt breaking off in what could be considered a "blind hole" is just cut out the affected area and replace with flat bar that has a nut welded to it.

 

[macleanflood]

An artist with an oxy-actylene torch could melt that out with minimal damage...

-Mac

 

[azrattler]

I broke the #3 (just in front of the rear tire) driver-side body mount bolt while trying to remove it (thank you New England rust).

The issue is that the bolt is broken so far internally that it's impossible to weld anything onto it or grab onto it with vise grips. I've drilled a good-sized hole into the bolt, but I've yet find an extractor that's long enough to even reach the bolt. Here's a picture for reference:

View attachment 655447

I've seen a few people saying that body mount is impossible to access from above? Or if you ARE able to access it, you wouldn't have enough room to do anything to it. Is this true?

I don't love the idea of drilling the bolt out and ruining the threads and having to tap them.

Any suggestions? Tips? Tricks?

First, get a 4 sided extractor. They're tapered with a relief cut along each corner to grab the bolt tightly. Depending on how deep the broken bolt is, you might have to weld an extention onto it. Next, use a small welding /brazing tip on your oxy/ acetylene unit to heat the bolt up,( be carefull not to cook the rubber cushion)! Spray some rust buster up in there, tap the extractor into it and pray it takes it out! Always worked for me. P.S. Don't use the spiral extractor. Unless it bottoms out in the hole it will just make the bolt tighter! I have a Proto set # 9500A See pics.

 

[azrattler]

First, get a 4 sided extractor. They're tapered with a relief cut along each corner to grab the bolt tightly. Depending on how deep the broken bolt is, you might have to weld an extention onto it. Next, use a small welding /brazing tip on your oxy/ acetylene unit to heat the bolt up,( be carefull not to cook the rubber cushion)! Spray some rust buster up in there, tap the extractor into it and pray it takes it out! Always worked for me. P.S. Don't use the spiral extractor. Unless it bottoms out in the hole it will just make the bolt tighter! I have a Proto set # 9500A See pics.

View attachment 655510

View attachment 655511

Make sure the hole you drill is deep enough to allow enough meat for the extractor to grab and at the same time, not too big in diameter. The bigger the hole, the thinner the wall! You risk cutting into the threaded hole! It's a ballancing act. You want to use an extractor that's big enough to do the job but not too big!

 

[azrattler]

Make sure the hole you drill is deep enough to allow enough meat for the extractor to grab and at the same time, not too big in diameter. The bigger the hole, the thinner the wall! You risk cutting into the threaded hole! It's a ballancing act. You want to use an extractor that's big enough to do the job but not too big!

The extractor set calls to drill a 5/16" hole at least 1/2" deep for a 1/2"diameter bolt whole using the proper extractor. In regards to my earlier post, before doing any welding, see if a 5/16" square socket and extention will work