I am trying, very unsucessfully so far to change my trailing arms. I don't think any of the rear suspention has ever been apart. I think I need to get a torch to heat rusted bolts, more specificly the lower shock mounts and the trailing arm center bolts.

Has any one used the Bernz o matic OX2550KC Torch?http://www.bernzomatic.com/PRODUCTS/...3/Default.aspx

It uses Oxygen and Propylene gas. How hot does it get? Will it heat frozen bolts enough to get them out? What is Propylene gas anyway?

Thanks

 

on the trailing arms the rubber bushings fuse to the bolt shank,
I tried penetrating oil, Heat and the BFH !...No go,
Finally bite the bullet, and broke out the saw-saz.
it's not easy and you have to cut off both ends of the bolt,
but they will come off ! good luck... 69VETT
second worst Vette job !
#1 worst Vett job ... working under/behind the dash !

 

Bernzomatic is part of the corporation that owns us(Lenox). Lenox also has these torches and they do not get hot enough to really do a good job cutting.

The propylene gas is called Mapp gas. It does burn hotter than propane and most of the plumbers like it because it saves time heating up copper pipes. Not a cutting gas though even with oxygen. Get out the sawzall for the trailing arms. The smell from the burning rubber also is terrible.

 

Try Loctite Freeze and Release, I have two bottles but haven't used them yet. If you do try it let us know if it works

 

I have a propane cutting tip (a lot more holes than the acetylene tips) for my Victor cutting torches and years ago I used it to cut up to 3/8" steel, took forever and used a lot of gas. Mapp gas should be hotter, but I agree, not that little set.
And besides, who wants to deal with the melting stinky rubber by using a torch for that.

 

Ahhh. You are talking totally different type of torches. Thems be cutting torches!

 

I haven't used that torch but I got this info on the gas.

MG9 - 16.92 oz. Fat Boy Max Power Propylene Fuel Cylinder
Ideal for medium to heavy soldering and brazing
Flame temperature in air = 3600 F

I can tell you this. Add Oxygen and it will be hotter. Since all you need to do to free a rusted bolt is to make it glow red and steel is glowing red at around 1600 F and liquid at under 3000 F it should be able to free rusted bolts. I'm sure it won't cut as well as Oxy-Acetylene (around 5500 degrees) as a previous poster stated, but if you just want to loosen bolts it should work. It should also work for brazing since that just requires enough heat to glow red.

I just looked up the price and at $109 for the kit and $12.50 for an oxygen tank you might be better off in the long run by looking at an Oxy-Acetylene kit with refillable cylenders. It depends on how much you think you'll use it.

 

I figured I would have to cut the TA pivot bolts with a sawzall. I wrapped the shock mount in foil and submerged it in PB Blaster for 2 days. I tried a removal tool (whacker) and an 8lb hammer and it won't budge. I also tried a bearing seperator and it broke. I may have to cut it out too if heat doesn't work. The adjusting bolt for the strut, the nut snapped off with my impact gun. I tried beating on the bolt with a drift and 4lb hammer, it hasn't moved at all.

I wasn't figuring on cutting anything with a torch, just heating it to break the rust loose.

 

You can get the little oxy/acet set that A/C guys use pretty cheap used.
I have a set that I can carry up a ladder to a roof and they can do anything the big bottle sets can.

 

My local Home depot has it for $49.95 and cylinders are $8 each. I would love a oxy acteylene torch, but I have a son in college and this repair has grown from replacing a bearing to possibly replacing both trailing arms.

 

If they are truly that rusted together, then I would start drilling out the bolts and using a sawsall etc. Will be easier, faster and a lot less expensive.

 

Do you really think it would be easier and faster to drill out the bolts than to heat them and drive them out with a hammer?

 

Most likely the bolts are rust welded in the steel sleeve that goes thru the rubber bushings. You'd have to heat the entire bushing to break it free, and then keep it hot enough to stay free while you beat it out. The rubber is going to burn out first and that'll stink bad enough. Then remember that the car is fiberglass and that will burn too. If you don't own a Sawzall, rent one. It'll be faster, safer, and cheaper in the long run. What you spend in Mapp gas or whatever, plus the need to keep the fire under control, you will be ahead of the game buying Lenox blades for the saw. Not counting your time.

 

I restore snowmobiles in the off season, that torch is no good except for brazing, Too expensive to use daily, buy a real oxy-acet. or use a sawzall-good luck

 

I bought a torch, an oxy/acetylene torch. I only used it to get the shock mount out after the TA was out of the car. The bushing was right up against the side of the support and I couldn't get my sawzall blade to the bolt and was having no luck sawing the bushing. Even with the oxy/acetylene torch I couldn't get the mount out. I just got it to move enough to get the sawzall blade to the bolt.

I cut one side of the camber adjusting bolt but the other side was just like the shock mount. I couldn't get my blade between the bushing and the support bracket so I ended up drilling the camber adjusting bolt out, which took about 2 hours and 3 different sizes of progressively larger Irwin Cobalt drill bits.

The TA pivot bolt cut pretty easily, at least compared to every thing else. I used one Lenox Gold 18 tpi titanium coated blade to do both sides. I used alot of cutting oil and had it out in 2 1/2 hours.

I could not find any Freeze and Release so, no report on how it works, but it does sound promising.

Thanks for all the advice. I think I would have been disappointed with the little torch.

 

Thanks for the plug. I keep telling everyone about these blades. They are extremly tough. We actually have a better one that will be available very soon.

 

Good advice here, the sawzall (with good blades) is the most recommended tool for the job.

I have the oxy-mapp setup you are asking about, and it will work to loosen rusted/stuck parts. I used it several times in my rear-end rebuild. Oxy/propane and oxy/mapp are MUCH hotter than a regular propane torch. Oxy/mapp is good for brazing too. If you can find it for $50 as mentioned earlier, it's not a bad deal.

Good luck!