can't figure out my brake problem

[Guest kentmocr250]

i am putting my car back together '75 z, new pads, & steel lines instead of rubber lines. i have power bleeded, manualy bleeded with a helper also. 1) i have very little pedal. 2) my front brake reservoir fluid is turning dark. 3) fluid is coming out thru the plunger area into the interior where the plunger goes thru the fire wall. i changed the mast. cyl., no change , retightened all the fittings.no clue? need advice

[280Zone]

Once you have drained all or most of the fluid out of the system, it takes awhile to get all the air out, but that doesn't sound like your problem. If you have fluid coming into the car at the brake master then that would be that the seals must be bad or damaged during install. Otherwise try to determine exactly where the fluid is coming out, it has to be the master seals or a fitting somewhere. Once you find it it should be easy to fix.

[johnc]

Sometimes when bleeding an old brake system you overextend the seals in the master cylinder by pushing the pedal to the floor. That pedal probably hasn't been near the floor for years so the master cylinder piston seals now get forced through varnish and dirt built up in the bore.

 

Any leak is bad. Replace parts to fix the leak. Also, expect to go through a couple quarts of brake fluid bleding a purged system.

[Mike C]

With the clutch MC, when it leaks fluid can run into the car. Because of the diaphragm booster, that does not happen with the brake MC. Sounds like your booster failed after an old MC crapped out. It still has fluid in it and that is getting in your car. Must be a lot of fluid also...Unless you flushed the lines completely, it is just old fluid backflowing into your new MC. The rear brakes need to be adjusted out as far as you can get them, otherwise you will always have a spongy pedal.