Cannot remove old brake lines

Sometimes the rust wins.

I will get a picture or two for you so that you can give it your best shot prior to sawing stuff off and starting over.

Looking for Mr. Camera now.

The Medic

Hi guys. Let me add a few comments of value. First of all, wash all that penetrating oil off, or be sure to remove and replace any parts that came in contact with it. A single drop of any type of petroleum product will contaminate all of the brake fluid and destroy all the rubber parts that come in contact with brake fluid. The only acceptable repair for that is to replace every part that has a rubber part in it that contacts brake fluid. That includes the calipers, wheel cylinders, combination valve, master cylinder, rear height-sensing proportioning valve, if one is used on your vehicle, and the rubber flex hoses. That gets to be a real expensive repair.

For removing the steel lines, it sounds like you are making too big of a production of the job. For any steel line that is being replaced, use an air-powered cutoff tool, or even a hacksaw, to cut the line right next to the soft metal nut, then use a ratchet and a six-point socket to remove the nut. If the corners are already rounded off, pound on a smaller socket.

To remove the rubber flex hoses, just cut them too. The slide clip often rusts away leaving no solid flange to grab with a pliers. Use a small hammer and a punch or a flat chisel to attack what's left of the clip. When they are that rusty, you can usually crack them in half, then push the pieces out of the groove on the hose.

When we do this type of repair for a customer, time is money. Parts will be flying and dropping on the floor. We often resort to using a torch to get the line nuts loose from rubber flex hoses, but that is only when we want to save the steel line, but the nut is rusted to it. A propane torch will probably not get hot enough to be effective, but you can try it. Be prepared for a loud surprise. If you get the fitting hot enough to do the job, the rubber hose will appear to explode with a loud bang and a bunch of smoke. It makes for more excitement than is warranted. There will be no pressure in the lines. The explosion is actually the rubber hose melting, then squirting out of the really tight crimp. You can accomplish the same thing by just cutting the rubber hose with a knife, but the goal of the heat is to expand that crimp fitting so the line nut can be worked loose. Just turn the nut enough to know the threads are broken free. Now the crimp can be unscrewed from the nut, then you can work on the nut, with heat if necessary, to free it on the steel line. Once it can be spun with a wrench, lubricate it with Brake Parts Cleaner to wash the rust out. Remember, do not use any grease or other petroleum products on those nuts.

Breaking loose steel brake lines and and hoses is sometimes a chore.

Breaking really rusty ones can go either way, breaking them loose/or just twisting the darn lines and maybe breaking them.

Mud grease/goo/and them having been sprayed with "Rhino Liner" or other bed linings really makes it a challenge.

You must clean this from the fittings just to be able to start the task.

To get to your fittings, A pressure washer/ purple power/chipping with a sharp screwdriver and a hammer might scale the stuff off. Carefully waving a propane torch over it may soften things up. (Let's not cook something that needs to stay, such as a hose). Along with that, insure you have no fuel leaks.

We do not want to heat the lines up real hot! Just get the crud off!

I do not recommend heating fittings to remove them from other fittings, cooking the fluid within is surely not a good idea.

Let's not use oil on the fittings either, it can get mixed in with the brake fluid and swell up (ruin) rubber stuff in the system, such as wheel cylinder cups and lot more stuff. Basically, your brakes could fail from ignorance!

We really like to have "pretty" fittings to deal with, not stripped and smeared nuts.

Regular wrenches should not be used on the "flare nut" (the one with the steel line through it!) You can use them on the brake hose and even the "blocks" they screw into.

A "flare nut wrench" should be used on the flare nut. As regular wrenches will strip the nuts.

A flare nut wrench will strip too.

I found a method that works really well just to break them loose. Then you can continue the normal way with the wrench.

The trick is to use vise grip pliers!

Not on the nut on the wrench

Sorry this took so long.

In my pictures below (which I had to download new drivers in my computer to read them, dang Grand youngins!) My computer guy had to figure out what had changed, good thing I fix his Jeep!

I could not find a pair of small "needle nose" vise grips for the pictures, They work the best in a tight spot. The original kind can work too.

Position the pliers so they don't "bottom out" we only have to break the threads loose. Less than a 1/4 turn. Then even a regular wrench should back them the rest of the way out.

When you are "pulling" the flare wrench, you need to be back-holding the other part with a wrench too. Basically, this equalizes the pressure and the goodies in-between the wrenches should not move around which might bend or break something on down the line.

Sometimes a quick love tap to the flare wrench with a hammer will break the bond of the threads.

So

Remember

Back hold

vise grips (regular or needle nose) will keep your flare nut wrenches from stretching and stripping and gripping really well!

Just have to break it loose, then you are home free!

Keep us posted,

The Medic