Repairing body bolt hole threads

GreyWisent

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There are a couple of instances where parts are attached to the frame of the vehicle via body bolts, threaded directly into a machine hole in the body of the car.
Some examples are the cross vehicle support bar bolts, the degas bottle support bolts, the fuel hose bracket bolt, etc.

In my case, some were damaged by rust. Others by me (in my infinite wisdom) using an impact wrench, such that little bits of the coiled thread came out.

Given that my metal fabrication and machining knowledge and experience is pretty much zero, I hope someone can help:

I'm hoping to keep using the same bolt. Are there any solutions for that?
I'm thinking of just tapping the holes again using a chaser tap. As far as I know, the success of this will depend on my luck, based on how much of the thread was eaten away.
Is there anything I should avoid? Am I likely to cause more damage than actually repair anything?

As for rusted (or perhaps slightly cross threaded bolts), I'm also planning to chase the threads with a die.

Again, this is about body bolts, where perfection is significantly less important than in dealing with things like head bolts.
 
Thanks.
I was considering Heli's. They're a great solution, but I don't think it merits the cost for my particular application.
 
If you have pulled the threads you don't have much choice?
Heli-coils or something similar. Drilling out to the next bigger size usually does not work because these threads are not in solid metal but some kind of sheet metal attachment that is thin walled.

I NEVER use impact tools for disassembly any more. I just tore up to much stuff and had to try to repair the results. Now I use penetrating oil/heat/cold and back and forth with a hand wrench to get the tough bolts out without damage.
 
If you have pulled the threads you don't have much choice?
So, I'm wasting my time tapping/chasing the same size, right?
Drilling out to the next bigger size usually does not work because these threads are not in solid metal but some kind of sheet metal attachment that is thin walled.
Was afraid of this...

I NEVER use impact tools for disassembly any more. I just tore up to much stuff and had to try to repair the results. Now I use penetrating oil/heat/cold and back and forth with a hand wrench to get the tough bolts out without damage.
Learned the hard way and too late. New to impact tools.
 
You may want to look into "rivet nuts" (look it up on Google). A parts store may have the tool needed for installation as a rental.
 

I suppose so. I saw the use of such a tool with threaded rivets on one of the car shows I watch on TV. I believe they were attaching fender flares to a jeep by first drilling a hole in the fender, inserting the threaded rivet and then screwing on the fender flare. They also inserted larger threaded rivets into the frame to mount suspension components, but the tool they used looked more like the scissors type.
 
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I believe 'Riv-Nuts' is a brand name. They are available in a variety of sizes and materials. They're available at places like Home Depot, Lowe's, Grainger and Fastenal. They're an excellent suggestion for the locations mentioned above.

KS
 
Got me one of these:


Was very cheap on amazon, but it's probably not that great. Haven't had a chance to use it yet though - been blessed with other headaches in the meantime.
 

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