Can't loosen brake cylinder line......

geronimo wrote in news: snipped-for-privacy@4ax.com:

If a flare wrench doesn't loosen it, just cut it off with a brake line cutter (available cheaply just about anywhere). Get some cheap generic brake line (cheap) from the same place you got the pipe cutter, rent a flaring tool and make your own replacement section.

Get an extra piece of brake line to practice your flares on until you get them right.

This happens a lot with bleeders.

Get a medium size pair of vise grips and adjust them so as to be tight on the nut when you clamp it on.

Using a torch (acetylene or oxy/acetylene preferred), heat the line nut to a high temperature, not cherry red. Your MAPP may work, I've never used one.

When you remove the torch heat, quickly clamp on the vise grips and GENTLY rock the nut back and forth (tighten and loosen) in it's threads. Remember, it's a twenty year old car. Most of the rusting is usually between the nut and the line, not necessarily in the threads. That is why you do this gently so as not to break the line by twisting it off.

It should break free and loosen. If you break it off. you will have to replace a section of line. Line comes in different sizes and end nuts. Just take the old section into a DIY place, like auto zone and they should have some DIY sections the right size. A new nut will come on an end if not both. You can usually bend it by hand once without kinking by being gentle and not bending it too tight of a radius. If you have to get into custom work, you will have to invest in a double flare tool and a bender. Good luck.

To answer one of the OP's original questions, there is no rubber O ring or gasket on the brake line so you don't have to worry about ruining a gasket with a torch, although the seals on the wheel cylinder may be damaged. If you are replacing the wheel cylinder, then that is not too much of a worry.

I recommend replacing all of the brake fluid if it hasn't been replaced in the past 2 to 4 years, and if you use a torch, I would replace the brake fluid.

If you end up replacing the brake line, do not splice the replacement line. Run the replacement line all the way back to a factory fitting, which is probably the load sensing proportioning valve mounted on a cross member forward of the spare tire.

Ha ha... Tegger is sure right on this advice. I replaced a bunch of brake line on my Suburban and ended up with several "practice" double flares on the bench. Also, after trying to reproduce the man bends in the line, my head turned around 360* just like in The Exorcist. Here's a photo of a flare wrench btw. jor

A couple of thoughts come to mind. Can you soak it with PB Blaster or equivalent and let it soak for a couple of days? If you can't get the wheel cylinder off, can you rebuild it in place with a kit? WAAAAAAYYY back in the day, we used to rebuild them in place like that.

Would be ok to rebuild, IF the body is made of cast iron. Aluminum cylinder bodies tend to pit once the anodizing wears through.

Can I put my MAPP

No o-rings to worry about, but be aware that brake fluid can burn. You also stand a chance of burning the paint on the backing plate and would need to touch-up paint those areas to minimize future rust. A MAPP flame heats things up very fast.

Use a flare nut wrench to loosen the line fitting. If you haven't rounded the nut edges too bad and can get the wrench completely on, give it a sharp rap with another wrench (17 or 19mm) and the fitting should break loose. Another option is to clamp a vice-grip on the nut and give that a sharp rap. Just make sure to grip the nut on what ever is left of the flat edges.

Forgot to mention the flare nut wrench size you'd need is 10mm. I've used a Craftsman 3 wrench set for years and it still serves me well. Be cautious of using a very cheap wrench because it can flare open and slip on the nut. Snap-on would be great to use, but will cost you. See is your nearest parts store rents any tools.

You are making me feel very very old