You can probably also rebuild it? If the parts store has a kit.I find that easier. Usually the leak is caused by car sitting to long and rust accumulating or seals just wear down and when shoes get thin they leak.
February, 6, 2011 AT 7:37 AM
Start by looking at your new wheel cylinder so you can see how it is attached. Here's a copy / paste version of a reply I just posted for another vehicle: Wheel cylinders are nothing serious but there are a few tricks that can make the job easier. Break the line nuts loose with a "line wrench" also known as a flare nut wrench. The nuts are soft metal and will be rounded off with a regular open end wrench. Flare nut wrenches grab the nut on all six sides instead of just two.
If the nut is rusted to the line, it will twist the line off. If you see the line starting to twist, stop, unbolt the wheel cylinder, pull it away from the backing plate, then unscrew it from the line. Then you can try heating the nut with a propane torch, then working it back and forth with the wrench to free it up. If it comes free, wash it off with brake parts cleaner. Don't use any grease on it, ... Yet. If you tried any type of penetrating oil, wash and scrub and wash and scrub to be absolutely sure it is all gone. It is critical that no petroleum product of any kind gets into the brake fluid. That will swell rubber seals and any other rubber parts including hoses.
If the line twists off, just remove the rest of it from the brass block on the rear axle. If you cut the line right next to that nut, you can use a six-point socket to get the nut off. You can buy premanufactured lines at the auto parts stores with the correct line nuts already installed for a few bucks. Buy one that is as long or a little longer than the original one. You don't have to follow all of the original bends perfectly but watch that where you run it won't put it closer to a hot exhaust pipe and it won't rub on a shock absorber.
Don't let the master cylinder run dry. Fluid will be dripping slowly from whatever is disconnected. Bleeding the air out becomes a bigger job if the master cylinder runs dry. A simple trick to prevent loss of fluid, if it's going to take you more than a half hour or so is to use a stick from the seat to the brake pedal to hold the pedal down about two inches. Gravity won't be strong enough to draw the fluid out of the reservoir past the lip seals.
When you're ready to bleed the air out, it's okay to let the reservoir drain until it's ALMOST empty, then fill it with fresh new fluid. Old brake fluid gets dark from getting hot. That's normal, but it also sucks up moisture. That promotes corrosion of metal parts and can lead to brake fade when the fluid gets hot. Brake fluid boils at well over 400 degrees. Water boils at 212 degrees and will vaporize. That causes air and a spongy brake pedal. You would like to get as much of that old brake fluid out as possible. The best way is to almost empty the reservoir before you add new fluid so it doesn't just dilute the old stuff.
When you remove the stick from the seat to the brake pedal, gravity will cause fluid to run to the wheel cylinders. That "gravity-bleeding" is the only method I use. When only fluid, and no bubbles come out of the bleeder screw, snug the screw just enough to stop the flow. When both wheel cylinders are bled, irritate the brake pedal a few times by pressing it down a few inches. That will wash the few remaining bubbles into the wheel cylinders. Open each bleeder screw once more to get those few bubbles out, then tighten the screws.
Some people prefer to use the "pedal-bleeding" method with a helper. The biggest thing to watch out for is to NEVER never ever push the brake pedal all the way to the floor. Some misguided people will tell you to do that. Even some text books tell you that too. Under normal operation, the pedal only goes half way to the floor. Crud and corrosion build up in the bottom halves of the two bores where the pistons don't normally travel. When you press the pedal all the way to the floor, you run the lip seals over that junk and they get ripped. Then you have a sinking brake pedal. That will require a new master cylinder.
Keep your container of new brake fluid sealed except when you're pouring some out. Also keep the caps on the reservoir except when you're adding fluid or want the fluid to drain down during bleeding. Brake fluid sucks moisture out of the air.
Look at the flat strut rod between the two brake shoes. There's an anti-rattle spring on one end. You should be able to push that strut rod at least 1/16 inch to compress that spring. Also look at the two shoes where they contact the big anchor pin on top. Both shoes must be making contact with that pin. If either of those things aren't as I described, suspect a sticking parking brake cable. That can cause a grabbing or sticking brake.
Once you're finished, you can spray some grease on the bleeder screw and line nut so they'll be free next time. I like Chrysler's "Spray White Lube". It goes on juicy, then the liquid evaporates leaving the grease behind.
Getting back to your car, you won't have that brass block in the middle of the rear axle because you have two individual brake hoses, one on each side. The rest of the procedure is the same.