My apologies if this is in the wrong place, I'm sure someone will move it if it is. Question for you all regarding removing the bolts from rear shackles. I've read all the posts: soak them for a week or two in PB, lower the suspension to take tension off the bolts, hit them/shock them to loosen the rust, etc...including heating the bolts to loosen the rust and corrosion. I'm a big fan of heating the nut, not the bolt, but I understand the nut is captured/welded inside someplace so, not accessible.
So, I'm guessing the usual way to heat them is with a torch: Propane, Mapp, Acetylene, whatever you've got. (I'm guessing oxy/acet is a no go...too hot ??)
What about...flameless heat ?? As a plumber, I have access to a tool that can be used to solder pipe fittings without flame, clamps on around the fitting and heats electrically to at least a couple hundred degrees. If I'm afraid of setting my Jeep on fire ( or is that an unlikely problem/concern), would this be a viable option? You think it would generate enough heat and work ??
Here's a link to Pipemaster Pro at Amazon:

 

I'm pretty sure there's Loctite on those. Not sure what temp it takes to break that bond.
I don't think you really need to worry about setting your Jeep afire. Keep a hose or extinguisher nerby just in case then if you're that worried. I haven't heard any stories of any Cherokees going up in smoke during shackle bolt removal. I myself have gotten things very hot and smokey under some vehicles and never burned one up.

Although my grandfather did burn his house entirely down while torching a little too closely to a fuel source on a car. His garage was the basement in a very old house so it went up quick. Everyone was fine by the way. Just the house and car were casualties.

 

Hack Saw, Chisel, Hammer, and elbow grease...

 

At some point it becomes hot wrench and new bolt time.

 

I think it would take more then a couple hundred degrees

 

Don't think that would generate enough heat to be of much use, soldering happens at low temps, 450-600*...and, getting that tool onto anything close to where it needs to go, isn't gonna happen. Way to think outside the box, but I don't see it working.

Not sure on the temp needed to break the loctite bond...but again, getting heat where it needs to go is the issue.

 

There Is holes in the uniframe that you can stick your torch tip in to heat up the nut on the inside. Using a torch is the best method IMO.

 

Two seconds on the trigger of a hot wrench and the problem is solved. lol

 

...which im assuming is an oxy/acetylene torch?

 

Yep... Or in my case because it is much cheaper but harder to handle if you are not on your game, an oxy/propane torch. It is much easier to do pinpoint work with acetylene.

 

Red Loctite releases at 550° F. You'd want to get it hotter than that to be sure the threads reach 550°. Steel isn't the greatest conductor of heat, so even if you have an iron that can reach 600° at the tip, the bolt probably won't transmit that heat down to the threads.

Use a torch.

 

So, if i have an acetylene torch and can stick the tip in a hole in the unibody "frame", I should heat the nut? Won't i risk weakening the welds and having the nut break off?

 

I just removed mine today. I sprayed them with PB about a week ago and sprayed them with WD-40 this morning. I used a brake-over and socket. I just worked it back and forth a little at a time until it broke free. Once it broke free, I just cranked them out. They were tight for a bit, but came out fine.
You always want to work the bolt back and forth. Don't just bow up and pull like most people.

That is a little trick I learned back in my body shop days. Not 100%, but works in most cases.

It didn't work on my shocks.......

 

I was having a heck of a time with one of my shackle bolts on the 2000..
CCken passed on a great little trick if all the things I try didnt work. This was a last resort kinda thing.. But heck I did it anyways..

Pic from CCKen shows a little access hole cut right above the tip of the bolt.. I was able to get heat down to the bolt tip. Then hit it with a shot of PB,,in a puff of smoke and a turn of the wrench it broke free.

Here is a pic where to cut a small access hole. Pic from CCken

 

I think we're talking about the spring eye bolts and not shackle bolts that are on the rear end of the Jeep. For the spring eye, if you reef on them, you just end up breaking the weld-nut. With heat (I used Oxy/MAPP), you smoke the bushing a lot but it will come off. I had to cut out the floor from the inside on my parts jeep to get access to the weld nut that was spinning. Then I could get a wrench on it. Heat is your friend. I don't think the nut gets hot enough for the weld to melt and if you do the bolt side anyway, there's little chance. PB blaster, breaker bar, heat, pull and repeat. It either comes off or breaks the weld nut. Not a big deal either way really.