View Full Version : Brake Bleeding Question

07-08-2006, 11:26 AM
Does anyone know what, if any, type of thread treatment I can use on the brake bleeding screw?

Bleeding the brakes has become almost impossible. The fit between the male and female threads is so loose that when I break the screw loose to bleed the brake fluid air sneaks in between the threads. (Hard to explain).

I was thinking about an anti-seize or teflon tape type of thread treatment or
should I just buy new bleeder screws?

Let me know, Thanks.

07-09-2006, 10:07 AM
What bleeding method are you using?

Even if your threads are worn, air should not be entering back into the system. The bleeding screw seals itself at the flared end, not the threads.

I've had air get into the system using the one man method with speedbleeders. Air would get past their threads when I relaesed the brake pedal before I could get out of the car and tighten the bleeder screw. They would work fine if I removed them, cleaned the threads, re-applied pipe sealant, let it dry and then re-install. Not exactly the labor saver they claim to be.

There just is no substitute having that second person at the brake pedal unless you buy a pressure bleeder and those are a PIA to clean after every use.

07-09-2006, 01:18 PM
Anti-sieze or pipe thread tape may not be a good thing if it gets into the brake line. I would agree with PETSNKE on the two person approach (as long as the other person is not too aggressive with the brake pumping since that could cause air to get trapped in the lines).

07-09-2006, 01:32 PM
Yes, I use the two person method. I wife isn't real happy about it but she'll pump the brake pedal for me.

When bleeding the brakes I typically turn the bleeder screw about 1/4 to 1/2 turn to allow the fluid to be pushed out. Even at the 1/2 turn, the fit between the bleeder screw and the caliper is real loose and appears to be letting air slip back into the system. I also use a piece of clear aquarium hose to fit over the screw tip. The other end of the hose is in a clear bottle below the fluid line. I can see all the fluid coming out. After each pump of the brakes the system picks up a number of small air bubbles. I loosen and tighten the screw in between brake pedal pumps and I can see that air is not being drawn back in from the screw top. That's why I believe the air is getting past the threads.

I purchased a set of the speedbleeders but they don't very well. I cannot get mine to seal closed. A good mash on the brake pedal and the speedbleeders start to ooze brake fluid. I pulled them out and threw them into the back of my tool box.

I think I'll try some thread sealant next.

07-10-2006, 08:32 AM
I agree with everyone's post here .. if you are getting fluid/air past the threads, you are opening the bleeder too far.

If however they ARE worn from multiple use, all you can do is replace the caliper or have it tapped and helicoiled. they aren't that expensive and worth it if you drive your car daily or at high speeds. (keep ya from blowing the line and NOT being able to stop)

I use a bleeder kit - but if you car is like mine - you'll need to turn the engine over for the vacuum to pressurize the lines. Only took like 2-3 turns of the engine then I shut it off.