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Broke bolts

Jayhawk_Aviator

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Jun 2, 2015
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123
Help!

I have an old Jeep cj7 that I am restoring. It seems 75% of the bolts I try to remove from the body tub are rusted stuck. I have tried every trick in the book, Kroil, pb blaster, numb nuts, torch, etc and none of them have loosened. I’ve had to drill, and most of these are big bolts and takes forever.

Anyone have any innovative ideas?
 
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mrpizza

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IL
I've heated them up before and hit them with a wax candle to melt wax into the threads. Worked slick on an old rusty brush hog blade bolt.
 

Bighead38

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Just a little plumbers torch

That’s why. I haven’t met an old bolt that the oxy/act torch couldnt beat.

Do you have a good impact or breaker bar. Get it as hot as you can and spray the penetrant. Repeat a couple times. Then as hot as you can and while the bolt is hot hit it with the impact or breaker bar.
 

AldeanFan

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Niagara on the Lake
I like the heat and quench method.
Heat it glowing hot and quench it with water.
Try to heat just the nut and not the bolt inside it. The idea is to use the expansion and contraction to break the rust bond.


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OP
J

Jayhawk_Aviator

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How do you know how hot? It’s a painted / visible section of the floorboard. I’m assuming the paint in that whole area will be toast? Most of them are welded body nuts, so I can access the top of the bolt, but no good way to access much else.
 

techieman33

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This guide may help you out.
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Bighead38

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How do you know how hot? It’s a painted / visible section of the floorboard. I’m assuming the paint in that whole area will be toast? Most of them are welded body nuts, so I can access the top of the bolt, but no good way to access much else.

Literally make it cherry red but I don’t think you can with the heat you have. So get it as hot as you can.
 
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dogdog

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Would a mini ductor work to heat it without burning the paint?

it will Sort of, but if there are paint in the heat induction area it will burn off those paint...

basically it's this... the steel object inside the coil gets heated to dull red ...if the paint is on the bolt or metal object, it will burn off.... the dull object radiate heat to the surround metal as well some what so if the heat radiates to the other area close by it and hot enough to burn the paint on hear by surface, it will...

induction heaters are nice, but not a magic cure all... your coil has to be able to warp around the object being heated... otherwise.. it's just won't work.

Learned a trick from an old timer....

he told that some times tighten the bolts with the impact first then try to loose it, and repeat, some times get stuck bolt off better than if you just try to impact it off... Didn't work on Honda, not sure something about these metals they used.
 
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cmandp

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A propane (or even MAPP) torch won't do it for removing rusty bolts on vehicles. At minimum you need the cheap little Berzomatic set that uses MAPP and oxygen. But investing in a oxy-acetylene setup is really going to be best if you have a lot to do or will work on rusty bolts often. Now ask me why I haven't taken my own advice above. :headscrat

A welder helps too once you've broken the rusty bolts off. :lol_hitti
 

Finky198

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Dogdog The impact gun trick has absolutely worked for me in the past, but it’s sometimes to risky... so I’ll use an air hammer to just induce some vibration. Great tip...

A propane (or even MAPP) torch won't do it for removing rusty bolts on vehicles. At minimum you need the cheap little Berzomatic set that uses MAPP and oxygen. But investing in a oxy-acetylene setup is really going to be best if you have a lot to do or will work on rusty bolts often. Now ask me why I haven't taken my own advice above. :headscrat

A welder helps too once you've broken the rusty bolts off. :lol_hitti


I call totally bs on these claims that little torches don’t work.
I use a ts8000 running on propane everyday for stuck fasteners and it works just find its might take a little longer then our oxy ace setup but it’s grab and go. All in all it seems to be much more about the process than anything...

last week I had to remove 2 9/16” frozen exhaust flange bolts from a 2001 ford (it’s in great shape it had no front passenger floor pan... well it does now...) with the same torch and a xtra long ratchet. It’s how you approach the problem that makes it successful...

clean the threads with a wire brush, heat the nut get it as hot as you can and quench with penetrating fluid. possibly more than once and then remove. If it binds turn it back in a 1/4 or 1/2 turn to break the bond and continue backing it out if it binds again repeat the same 1/4 or 1/2 turn until it release. :beer:
 
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mrjaw14

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Oxy Acetylene torch is the best way. another way to heat a bolt is weld to it. If you weld a nut to it and fill the center hole, depending on the size of the bolt that can heat it enough. Some people have better access to welders than torches, so wanted to mention it.

I have a torch but no tanks for it...man they are expensive!
 

ransil

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pa
If they sre not threaded into anything get a large bar and break them off.

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Mitchw123456

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Aug 28, 2013
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kemah tx
you say big bolts on the tub so I'm assuming you are talking about the body mount bolts to the frame? If this is the case you're fairly screwed unless you intend to replace some of the floor pans. I'm assuming you aren't rattling on them with a large impact as the hold down tabs on the tub side body mount bolts would have sheared off and just left you with a spinning nut you can't loosen? if this is the case, and what I have done in the past is just cut you an access hole to the nut side of the body nut bolt in the tub. if you do this you have to only drill about a half inch of the long body bolt out or you have something to hold onto as back up to break the bolt off with your impact. with your other bolts which I'm assuming its bolts like your roll cage bolts to the tub? I would just take a cut off wheel to the heads of them and punch them through the tub and out.
 

cmandp

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I call totally bs on these claims that little torches don’t work.
I use a ts8000 running on propane everyday for stuck fasteners and it works just find its might take a little longer then our oxy ace setup but it’s grab and go. All in all it seems to be much more about the process than anything...

last week I had to remove 2 9/16” frozen exhaust flange bolts from a 2001 ford (it’s in great shape it had no front passenger floor pan... well it does now...) with the same torch and a xtra long ratchet. It’s how you approach the problem that makes it successful...

clean the threads with a wire brush, heat the nut get it as hot as you can and quench with penetrating fluid. possibly more than once and then remove. If it binds turn it back in a 1/4 or 1/2 turn to break the bond and continue backing it out if it binds again repeat the same 1/4 or 1/2 turn until it release. :beer:

I admit I am not very patient with the plumbing torch (using propane), I actually have a ts4000 (I believe). My experience is that the flame is just not pinpoint enough and it's not hot enough so the heat just ends up soaking into other metal in contact with the bolts.

I do the other things you describe though cleaning the exposed threads, rocking the bolt back and forth, etc. Impact guns help a lot too but it can be done by hand just as well but with more effort.
 

homebuilt burner

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central Wisconsin
Penetrating oils need time. If high heat is not an option, try heat with a propane torch then penetrating oil then leave it sit for a day or two. Then more penetrating oil then more time.
 
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