Bleeding brake lines?

(Assuming you're planning to fix the leak first...)

I'm certainly no expert, but I've done this several times on various vehicles. One suggestion I have to make things easier on yourself is to get under there and make sure you can get the bleeder bolts open on each wheel before you start. Clean the area, loosen them up, run them in and out so they turn easy.

Unfortunately, on the vehicles I was usually doing this for (mostly vintage VW's), they'd been left alone so long and splattered with so much Minnesota road salt, that it was always a gamble whether the bolt would open or twist off.

Anyway, that's my one recommendation. I'm sure somebody else can tell the actual procedure better than I. My original instruction came from the "How to Keep Your VW Alive" book: have somebody pump the pedal many times, and hold it down firmly. Crack open the bolt on one wheel and let fluid squirt in your face till it comes out with no bubbles. Repeat. Then also repeat for the other 3 wheels. Start with the wheel farthest from the master cylinder and work your way closer.

I sure hope you were kidding about letting brake fluid squirt in your face or were you quoting the VW book.

You can attach a hose to the fitting and run the brake fluid into a bottle until it come out with no air bubbles.

Bearman

Yes, I was kidding. It's just the way things often go for me, underneath cars. Which I why I try not to spend much time there.

Something I think is really neat is a pressure bleeder made from an inexpensive plastic garden sprayer (the sprayers cost $15 to 30). You take off the nozzle, add some hose, make an adapter to replace the cap of the mater cylinder. I saw this described on a web page somewhere (Google it). Put some fluid in the sprayer, put on the lid, attach it to the master cylinder, pump the sprayer a couple of times, crawl under the car, put a hose on the bleeder nipple, loosen the nipple, and let it bleed. A lot nicer than spending half an hour yelling "up....down" to the guy pressing the pedal while you work the wrench.

I plan to make one next time I bleed my car.

Last week my friend did his brakes. I tried to get him to make one. He wouldn't. Then he went to the parts store to get some drums turned. He came back and said they had a catalog with a similar pressure bleeder advertised for $40.

Jim

You can also just get a one way air valve for fish aquariums and some tubing for under $5. Connect the tubing to the nippe with the one way valve in the middle and the end in a can. Just pump and top off the resivoir. Works well and cheap.

I tried that years ago using a bleeder hose purchased at the auto parts store. Air leaking back in around the bleeder threads was the problem I encountered then, which can probably be remedied with teflon tape.

Another point to remember when bleeding brakes with the pedal is to not push it all the way to the floor. The seal can be damaged in the master cylinder by pushing it into extents of the cylinder where it doesn't go in normal use. This is something I have heard from several people and makes sense. Before hearing this I had bled brakes on several occasions by pushing the pedal to the floor and don't remember having a master fail shortly afterward. Using the pressure bleeder eliminates this concern.

OK, you need to start with the wheel furthest away from the master cylinder. The right rear... even though there isnt a problem with it, it has to be bled. After that wheel, do the left rear. You want to make sure it is a nice squirt that comes out of the bleeder screw. Anyways, after that do the front right then the front left. After that they should be in great shape.

P.S. To get all the air out of the line.... pump the brake 4-5 times and hold (with the bleeder screw closed) then open the screw and let it squirt. Do this until the air is out. Make sure you dont ever let off of the brake with the bleeder screw open or more air will get in the line.

;) Dave

I've always used a clear glass jar with a piece of vacuum hose. The vacuum hose has to be long enough to reach the bottom of the jar. Put a couple of inches of brake fluid in the jar, connect the vacuum hose to the bleeder, loosen the bleeder slightly, and start pumping the brake pedal. The fluid in the jar prevents air being sucked back into the wheel cylinder. Top off the master cylinder after every 4 or 5 pumps to keep it from running dry. When you stop seeing bubbles in the jar, the brake is bled. I kneel beside the car and work the pedal with my hand while watching the bubble action in the jar.If the brake fluid is old, you can also see the fresh fluid when it comes through (color change). As a rule of thumb, bleed the longest line first, working back to the shortest line.