One of the holes that my front subframe mounts to was stripped out when I got the shell. I haven't really felt like dealing with it up until now, since I figured there would be a lot of work until it was done anyway, so I could put it off. But now I feel is the time to finally address this.

The threads inside are completely screwed. I figure that I can make a small hole in the frame rail (don't like that) and stick an M12x1.25 nut in there, and then bolt it in by holding the nut and threading in the bolt at the same time. Eventually, I'd have the nut welded onto the frame rail and have the hole patched up.

I've also found some sort of thread insert kind of thing, but I have my doubts as to whether or not it can actually hold the subframe.

Are there any other options that I can consider?

In case it matters, it's the rearmost bolt on the passenger side.

 

I would cut the threaded section out and weld in a new section with the nut welded in place already. Kind of like you already thought of. It's about a half hour job if you have a welder and a cutting wheel.

 

Where would I get a section like that? Or would I cut it out, weld the nut on, and then weld it back in place?

 

Why don't you try re-tapping it with a bigger tap and use a different size bolt.

 

Above
that is the solution.

 

Don't believe any of these guys Buy a Helicoil kit. This will permanently repair the hole and still allow use of the proper bolts while being just as strong as before the damage. My exhaust manifold has a few of them in there Local NAPA or machine shops should carry them. You'll need to know the size and thread pitch of the bolt so you can buy the proper kit.

How they work:

http://www.roadstarmagazine.com/modu...rticle&sid=233

 

This is a solution, but hardly permanent. The helicoil may loosen, break, or just fall out. I would go with a larger bolt.

 

Complete Bullshit.

 

As long as they are installed properly, Helicoils are absolutely permanent.

 

I'd try the Helicoil first if you can't do that then try re-tapping.

DO NOT start cutting holes in the frame rail and put a bolt in there, you'll end up with a big mess.

 

I had a Helicoil in my exhaust manifold for 4yrs and it went through one engine + turbo R+R and still held fine.

Helicoils are a good solution.

 

http://www.emhart.com/products/helicoil.html

"Heli-Coil® inserts are precision formed screw thread coils of stainless steel wire ...Typical Applications would include: Automotive,Communication, Aerospace, Military and the Defense industries

Heli-Coil is the approved Screw-Lock Screw Thread Insert source for Boeing Aircraft per specification
BACI12AE rev B"

If Boeing doesn't mind them holding their big *** planes together I'm sure they'll work just fine on a 2800 pound car.

 

xthephilx:

At least you now know you will not need to cut the frame--you have options.