Brake Problems...

[whisker]

I've been chasing down my brakes issues for a bit without much success..

It seems I can't get the rear brakes to bleed properly. I don't see any leaks in the lines- and ive replaced the wheel cylinders. Using my mityvac, i just keep sucking air- teflon tape on the bleeder.

I've replaced the springs on the adjuster- no dice.

The pedal is "low". Travels about halfway, then some resistance, then looses pressure to the floor.

Any help much appreciated!

[Fatmobile]

This is for the '81 dasher in your sig right?
Did they run the lines under the car or through the passenger compartment on the floor?
Try pressure bleeding by pressureising the master cylinder, so if it leaks it will leak out fluid instead of pulling air in.

[Quantum-man]

Hi,
Does your parking brake work correctly, ie rear wheels locked on within 3 clicks?
Is the rear regulator working correctly if there is one?
Maybe there is a leak at the master cylinder.
What difference does having the engine running make?

[bscutt]

I once pumped almost a quart of brake fluid into the rear carpet and padding on my 79 Rabbit before I found the brake line leak. I did not know they ran them inside under the carpeting. It's amazing how much brake fluid carpet & padding can hold before you see it. Now of course I am better informed and know to pull up the carpeting if I get a pressure loss.

[Quantum-man]

Well as he's not driving a rubbish Rabbit, nor a grubby Golf, but a dashing Dasher, the brake lines are external

PTFE tape? Shouldn't need that, as the sealing does not rely on the threads.If it's to prevent fluid rising up the threads/air entering, whilst nipple is loosened, then the nipple is blocked.

Bleed conventionally, by pumping brake, holding down between presses, whilst someone nips up the nipple, or use a length of clear tubing either with a simple valve in it or held vertically up the side of the vehicle.

[air-cooled or diesel]

never heard of teflon tape or sealant on bleeder valves. warning teflon tape even when 'used right' can later lead to problems. teflon tape is best used for shower heads and welders use it for tanks, on tanks it can later lead to blocked gauges. when you first put tape in it will seal, (when put in 'correctly'; 3 threads back), as soon as you loosen the screw the problems start. the tape will, if not cleaned fully out, travel down the threads and foul such things as oil lines, water lines, most any other line, hydraulic. (or gas for that matter). using sealant on threads will do this, unless when you loosen, you with difficulty can completely clean the threads.