Heat to remove bolts

Joined
Jan 1, 2013
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America's Dairyland
For the home user I've found that pre-treating with PB, heating with MAPP, then hitting it with CRC Freeze-Off will really take care of most fasteners. If the nuts have a lot of mass around them then this may not work.
 
Joined
Feb 19, 2013
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Prospect, KY
Straight acetylene without oxygen is nearly the same as propane so it is the addition of the oxygen that increases the BTU's. Flame color changes to blue and heats really increase with the complete combustion. Adding the oxygen to propane is not easy if you don't have the acetylene equipment already. Might rry a shop that has the equipment.
 
Joined
May 5, 2013
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Peace valley, Missouri
Oxygen acetylene torch is the only way to go because it concentrate the heat. Propane, mapp and acetylene alone has to big of flame unless the part is off the car then everything gets hot. They make a small torch outfit that uses a R oxygen and a MC acetylene tanks. Some people call them airplane or burglar set.
 

supton

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Nov 9, 2008
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NH
Originally Posted by Trav
I posted one similar to this for $200 but the tanks were not approved. This one is $300 but will do everything you need and they are safe. Tanks can be exchanged at airgas anytime. Cry once and get it done, it will save you more than it cost in the first few uses. https://www.lowes.com/pd/lincoln-el...krIjJ4QIVUMDICh1KUg_yEAQYASABEgLDRvD_BwE
Pricey, but might fit my needs quite well (which is minimal to none). I will give that serious thought. Only been 25 years since I've touched a torch in shop class. I don't want full size as I won't have any place to store for months to come--not unless if I want to store in the basement, and I'm rather leery of that (no garage, no shed). [Linked Image]
 
Joined
Nov 20, 2006
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MA, Mittelfranken.de
It is no more dangerous than a propane torch when left in the corner of the cellar over the winter. You can heat bolts, cut, gas weld, braze. In the salt belt nothing comes close for rusted buts and bolts.
 

supton

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Well, I got under the car and found it would have been more work than I could take on--whoever last touch the exhaust broke one of the studs but managed to get a nut onto a couple of threads so as to finish the job. To fix I would have to weld a nut on then back the old stud out--not a skill I'm going to quickly learn, nor desirous to do so while laying on my back. I do like this little torch though. Once home life settles down I will look into again.
 
Joined
Jun 3, 2015
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New York
A common mapp torch sold at Home Depot or Lowes for 65.00 will heat up a fastener red hot, enough to make it easier to remove. Anyone who thinks it isn't cut out for use has no idea what they're talking about. Usually fueled by assumptions about how the gas isn't authentic or as hot as it was x number of years ago. Also people basing the torch performance off of a different propane torch they used or a camping stove, that puts out a weak piddling pencil sized flame. A torch with a good torch head (like the swirl ones that bernzomatic sells) at full blast sounds like a jet engine and delivers serious heat. Is it as hot as oxy-acetylene? No way. Is it going to cut through metal? Not a chance. Does it get metal red hot. Yes. Is it effective at removing stuck fasteners? Yes. I suspect the mapp is overkill and propane will work too, just with a longer time necessary to heat it up. If you hold the mapp torch on a bolt it will turn red hot and glow brightly in less than a minute. If you're not looking to cut through a fastener a mapp torch is more than enough for a home mechanic to use to loosen fasteners. I've used the same mapp torch on dozens of rusted fasteners, all of them came out like nothing only after I hit them with the torch. I've used it on pipe plugs on intake manifolds, drain bolts on diffs, cat heat shields, exhaust fasteners, it's literally one of the best things I have ever bought. I've used it to remove rusted fasteners on 19 year old cars (and I live in the rust belt) that wouldn't budge with a ratchet alone. I don't even bother with penetrating oil any more.
 
Joined
Jul 26, 2007
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284
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NY
Originally Posted by NoNameJoe
A common mapp torch sold at Home Depot or Lowes for 65.00 will heat up a fastener red hot, enough to make it easier to remove. Anyone who thinks it isn't cut out for use has no idea what they're talking about. Usually fueled by assumptions about how the gas isn't authentic or as hot as it was x number of years ago. Also people basing the torch performance off of a different propane torch they used or a camping stove, that puts out a weak piddling pencil sized flame. A torch with a good torch head (like the swirl ones that bernzomatic sells) at full blast sounds like a jet engine and delivers serious heat. Is it as hot as oxy-acetylene? No way. Is it going to cut through metal? Not a chance. Does it get metal red hot. Yes. Is it effective at removing stuck fasteners? Yes. I suspect the mapp is overkill and propane will work too, just with a longer time necessary to heat it up. If you hold the mapp torch on a bolt it will turn red hot and glow brightly in less than a minute. If you're not looking to cut through a fastener a mapp torch is more than enough for a home mechanic to use to loosen fasteners. I've used the same mapp torch on dozens of rusted fasteners, all of them came out like nothing only after I hit them with the torch. I've used it on pipe plugs on intake manifolds, drain bolts on diffs, cat heat shields, exhaust fasteners, it's literally one of the best things I have ever bought. I've used it to remove rusted fasteners on 19 year old cars (and I live in the rust belt) that wouldn't budge with a ratchet alone. I don't even bother with penetrating oil any more.
I was gearing up to post something similar to this, thanks for beating me to it. MAPP gas/quality torch head works fantastic for heating automotive exhaust fasteners. I have been doing it for ~20 years, no one here could convince me otherwise.
 
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Dec 18, 2014
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Never had a problem using propane and penetrating oil. I just unbolted the OEM catback bolts on my 2003 Dakota with propane and an impact. In fact, I had to heat the pipe up so that it was glowing red and bend it off of my down pipe. Oxy-acetylene is unnecessary for a DIY mechanic IMO.
 
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