Trying to remove a rusted brake line

[GAmes]

This looks like the best forum for this. I have a proportion valve out of a 72 Chev on my workbench. I need to remove the brake lines to install them on a new one. One fitting will not budge. I have soaked it for 2 days in liquid wrench. The 7/16 flare nut wrench still spreads and threatens to strip the nut. Any suggestions? Is there a better penetrant than liquid wrench? A Better wrench choice?

 

[BFoughty]

might try a little heat and a pair of vice grips ... . if your not going to reuse he hose.

 

[JFaughn]

Not sure about yours but most pro. valves are made out of brass & have seals in them , so clamping & heating may make the part unusable .
I would put in a large vice that can cover most all of the surface , then cut off the tubing & use a 1/4 impact gun & socket .
I thing that Blast is a much better penetrater .

 

[GAmes]

might try a little heat and a pair of vice grips ... . if your not going to reuse he hose.

That's the thing. I need to use the brake line, it is the proportioning valve that is bad. It is short (about 6 inches total) and has 5 90 degree bends in it, so getting it duplicated locally is questionable.

 

[GAmes]

Not sure about yours but most pro. valves are made out of brass & have seals in them , so clamping & heating may make the part unusable .

I would put in a large vice that can cover most all of the surface , then cut off the tubing & use a 1/4 impact gun & socket .

I thing that Blast is a much better penetrater .

The valve is cast iron and it's rust has enveloped the fitting. Where does one find some Blast?

 

[Rebel Ram]

Vicegrip make a set of various sized pliers specificaly made for hex shapes. On the upper jaw it has a Vee that contacts two sides of a hex and the lower contacts the opposite flat. If you have enough room to put them on they grip the crap out of the hex and allow enough torque to twist off the fastener without distorting the nut or bolt head.

 

[Woodenhead]

Put a torch (propane will work) on the flare nut until it's red hot. Make sure the heated brake fluid has somewhere to go (out the other end of the line). Then hit it with water to chill it fast this will help break it free. You may have to do this twice. Grab it with a wrench (or vice grips by now) and spin the valve not the nut if you can. If you try and turn the nut you'll likely twist the line and bust it. Once the valve is off you can work at freeing up the nut on the line. Never done this with a proportioning valve but it's worked for me every time getting the rusted lines off the back of wheel cylinders without busting the lines.

 

[GAmes]

Thanks for the advice. I'll try to find the vice grips and try the heat method. Thankfully I don't have a time line.

 

[IanF]

Where does one find some Blast?

He probably means PBlaster. Available at most big-name parts stores. Works better than Liquid Wrench, IMO. Smells like wasp/hornet spray...



I've heard that another product - Kroil, I think - works even better.

 

[GAmes]

Just to let you all know. The PBlaster and special vice grips did the trick, I didn't have to use heat. Thanks again.

 

[EdK]

Ol' guy trick

Every time I grease the truck I put a dab of "overflow" from the fittings on each brake line fittings and bleeders. Haven't twisted one in about 30 years now!

 

[rbattelle]

Every time I grease the truck I put a dab of "overflow" from the fittings on each brake line fittings and bleeders. Haven't twisted one in about 30 years now!

Clever. If I can remember, I'll start doing that.



Ryan