Replacing brake lines-can't loosen
 

I order SS lines from our host but I can't get the old lines off. I purchased an 11mm flare wrench and I got one end off but I started rounding over the other end. I didn't want to ruin them so I stopped for now. I did let it sit for a day after spraying them with liquid wrench. What is the secret? I don't want to use heat.

When searching on this site for suggestions I learned some are having problems with the new lines not matting up with the stock fitting so getting the lines loose may be only the first battle.

You can use a propane torch to heat the nut up. Make sure you only heat up the nut, not the line. Do not heat to cherry red. Soak first with PB Blaster or Kroil.

PB Blaster & very little heat. Use the flair nut wrench !!!! on anything soft. Heat scares me on the hard lines. Don't freak if one gets bunged up, they can be replaced, just cost some bucks & time. Take your time.

I tried the flare nut wrench and liguid wrench penetrating oil. Maybe PB blaster or Kroil are better huh.


I found this while searching the net for oil comparisons. It is kinda off topic but interesting.

"The April/May 2007 edition of Machinist's Workshop did a test of penetrating oils where they measured the force required to loosen rusty test devices. Buy the issue if you want to see how they did the test. The results reported were interesting. The lower the number of pounds the better. Mighty interesting results for simple acetone and tranny fluid!


Penetrating oil . Average load to loosten. Price per fluid ounce
None ................. 516 pounds .
WD-40 .............. 238 pounds .. $0.25
PB Blaster ......... 214 pounds .. $0.35
Liquid Wrench ... 127 pounds .. $0.21
Kano Kroil ........ 106 pounds .. $0.75
ATF-Acetone mix.. 53 pounds .. $0.10"

Mine were stuck beyond loose when I bought my 77, and I went through the usual Kroil, PBplaster etc. etc. with the appropriate soaking periods.
The only thing that worked was to use a carbon fiber disc in the dremel and cut down toward the fixed fitting.
Continue with the flare wrench, and it should split open at the new cut mark.
As long as you're replacing the lines, no reason to preserve the old ones.
Another method is to cut the lines above the fittings and get a socket and/or box wrench on it.
good luck
Bill K

Use a flare or "line" wrench and instead of gradually increasing torque on the wrench with your hand, take up the slack with one hand and hit the wrench firm with the palm of your other hand.
If there isn't room for both hands to do that a hard rubber deadblow hammer works for hitting the wrench too.

This way almost always works better than torqing it loose which sometimes rounds off the points of the nut.

You'll have to do it a few times before you get the feel for it.. and if you're doing it 40-48 hours a week it becomes second nature and doesn't hurt your hand at all.

Anotherwords, "break it free"

I'll give that a try, thanks!

A team in the turbocharger reman plant found H2O (cheap ole water) to be the best penetrant and lube for rusty bolts.