I recently replaced the brake booster/MC/proportioning valve on my car, with one from a GXL, to go with my GXL brakes. It felt great, real firm and good response with my new hawk pads.



But yesterday, within a matter of maybe 3 stops, the pedal managed to hit the floor, with very little stopping power. Fluid dropped real low, so I refilled it. So I'm guessing it's leaking somewhere.



My question: should I used teflon tape on threaded brake fittings? I think I may be leaking where the lines meet the MC assembly. At least I'm hoping it's that simple.

 

oh, and would the tape also be good for where the calipers attach? or no tape at all?

 

I had the same problem after I upgraded my GTU with T2 brakes and a new master cylinder. Took me two full days to sort it out. I was finally able to find the problem with a friend helping me. He would look at each fitting while I pressed on the brake pedal and look for leaks. Turns out I had a fitting at the MC leaking and one of the connections on my brake lines was leaking. The MC connections I was able to just tighten the **** out of, the brake line I used some teflon tape. It's been about two weeks now, no problems.

 

technically with flared fitting tape is not needed

 

no tape. the line flare is what seals, the threads/fitting are just for applying the needed force against the flare to make it seal. Tighten it real good with a flared/line wrench. if the flares are dirty / damaged on the lines they will have trouble sealing.



sounds definitely like a leak, if you can't find lines leaking check to see if the back of the master cylinder is leaving a trail of brake fluid down the brake booster, if so it's a bad master cylinder.

 

and this specific type of thing sucks, i removed my abs to fix what i thought was my only brake fluid leak, two days later my MC was leaking.



sunuvabitch.



kevin.

 

ok, I saw some fluid around the flared fittings, so I dryed off everything, and tightened as much as I could before I thought I'd do some damage. This a used assembly, and there was no fluid trail down the booster, so I think it's good for now. As of midday yesterday, the pressure feels fine.