I've been doing exhausts for quite a while and most of the time I end up using the sawzall to just cut away the old and install the new system. But what if you are working to replace just a headpipe, cat to muffler pipe or even the exhaust tips pipe? The pipes needs to be separated without causing any damage to the good exhaust parts.
Like many of you I have struggled to find the idea solution to get an exhaust pipe disonnected and am doing this post to exchange ideas. When one pipe fits into another pipe, cat or muffler the trick is to remove the old rusted pipe withput damage to the good componets in the exhaust system so how do you do it? My technique is to cut the old pipe off about 3" away from where it joins to say a muffler. Now we have a small section of pipe stuck in there that has been crushed in place with an exhaust clamp. The oldest method that I know of is to apply heat with a Oxy acetylene torch to the outer member and to try and wiggle the inner piece out with a vicegrips. This will obviously work but in the process the metal is weakened by the red hot heating of the pipes.
Has anyone discovered a quick and easy way to remove stuck in exhaust parts without using the torch. All comments are appreciated.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, ZZP Intercooler, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

It depends upon what you're trying to do.

To remove tips, I'll take and rotate the tip downward ~90 degrees and then back up. If you do that enough times, it'll work loose. Or at least looser than it was.
I don't have a problem with heating the connection, either. I don't believe it weakens the metal. If you cool it quickly, it will actually temper the metal.
If you're replacing a muffler but want to retain the original tips, you can use a cutoff wheel to slot the end of the muffler pipe. It will make it easy to spread the pipe away from the elbow on the tip.

There really is no "neat and tidy" way to do it.

My recommendation would be that, whenever you assemble a system, slot the outer pipes, and then use stainless band clamps instead of crush type U-clamps.

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Raydar
88 Formula IMSA Fastback. 4.9, NVG T550

Praise the Lowered!

[This message has been edited by Raydar (edited 10-10-2011).]

Here's a method that sometimes works. Cut the old section of exhaust pipe off about 3" from where it enters the muffler pipe. Close an adjustable open end wrench on the pipe. Now take another wrench and use it to twist the wrench on the pipe collapsing it within. The pipe bends into itself and will come out.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, ZZP Intercooler, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

quote Originally posted by Raydar: It depends upon what you're trying to do. To remove tips, I'll take and rotate the tip downward ~90 degrees and then back up. If you do that enough times, it'll work loose. Or at least looser than it was.

Thanks for this tip. My pasenger side is loose and moving. I was wondering on how to get the drivers side loose for welding on new tips at some time.
-Joe

I, also, don't have a problem heating the parts. Very few exhaust pipes are heat treated - this is the only material that you will weaken by tempering (Heating, then allowing to cool). Note that this is not true of most fasteners - if you have to heat a fastener, you should replace it.

Best way for me has always been to tie one end to the frame or whatever if it is not already well supported, then I tie a bit of line around the cat or the tip, hook a come-along on it, hook the come along to a stud, or the bench, or the car in the next stall, take a bit of a strain, then apply heat - usually quite a bit. Sounds like a pain, but it has always worked for me, and is much easier than playing around with it for fifteen or twenty minutes trying to finesse it off.

Mike

Search for air chisel muffler cutters

[This message has been edited by 1fatcat (edited 10-10-2011).]