Brake lines leaking!

I just put on the a lift from rusty's and the brake lines are leaking (the longer replacement ones from rustys). They are leaking at all the connections. just tighten them better? jb weld them? that was a joke..I think.

Anyways...Thanks 88XJ

If its leaking, the flare nuts arent tight enough. They have to fully crush the hard line's flare to the inverted flare of the brake hose. The flare is already shaped to fit your old brake hoses, so it will take extra force to make a new seal. If tightening fails to stop the leak, the flare may have cracked.

this happened to me when i put on stainless lines. I bought a set of cheap ass flare wrenches, and they were sloppy on the fittings. I nearly dog-eared the nuts while tightening, not good.

youll have to bleed everything all over again too. If brake fluid came out, air got in.

When I installed my new (OEM) brake hoses on my Mini-Van, I got them leaking because I over tightened them. I crushed the copper gasket between the fitting and the caliper. I got a new copper gasket and tightened with a reasonable amount of force and NO MORE LEAK.

The copper rings under the banjo bolts (caliper) are standard size. At many auto supply places you can buy them in a box of ten for the same price as a single piece by part number. You may have to measure though.
Smearing a dab of oil on the flare before you start tightening, sometimes helps. As does a good flare nut wrench.
Be careful with the banjo bolts, they are hollow and snap off if tightened to much.
I have two pairs of vice grip pliers I use to tighten and loosen flare nuts. You have to be careful that the adjustment is right. Too tight and they crush the nut, too loose and they slip. it#s easy to screw it up with vice grips though, but as a last resort, why not?
I've got four sets of flare nut wrenches, two different types of Snap on and none seem to work well.

8Mud said:

The copper rings under the banjo bolts (caliper) are standard size. At many auto supply places you can buy them in a box of ten for the same price as a single piece by part number. You may have to measure though.
Smearing a dab of oil on the flare before you start tightening, sometimes helps. As does a good flare nut wrench.

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I just took the old copper ring to the auto store, and we matched up a new one, taking into account some squish.

I'd worry about using oil to lube the copper ring or flares as you tighten it down. Oil or any petroleum product will reek havoc on your brake system, it causes the seals (nitrol? some form of rubber, not the copper seals) to swell to 3 times their original size and will seize pistons in their bore.

For this application, just lubing the seal for tightening it down, I'm sure brake fluid will do just fine. Thats what I used when I re-did the job, just dipped the copper seals in brake fluid.

I'm sure its unlikely, but why risk it, I rather not get any oil or petroleum product near my brakes, so a drop can work its way in as you put things back together. Thats why the grease you use for brakes is silicon, well that and the high heat it has to withstand.

Also, clean the surfaces that need to seal thoroughly, caliper get really dirty, a bit of grit under that copper seal will cause it too leak.

Using a torque wrench might help as well, if you have a figure. When I properly tighten the banjo bolts, it was enough force that it was an effort to apply it, but NOT enough force that I felt discomfort in my hand from the wrench or I had to grunt. When I over tightened them, which made them leak, I grunted with the effort and could feel the discomfort in my hand, from the pressure of the hard wrench on the flesh. With these copper seals, tight as possibly can get it, is NOT better, you just want it tight.