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Topic: no pressure from brake pedal... (Read 1558 times) previous topic - next topic

no pressure from brake pedal...

All right people, I've  given up. Here's the issue; after converting to front/rear disk brakes using lincoln mark7 parts I now can not get any brake feel or pressue built up when the car running, the pedal just goes right to the floor.  With the car turned off the pedal slowly builds pressure
  I've bled the lines twice, checked for leaks and found none, and checked the lines for kinks. At first I was thinking the brake booster was the problem, but I'm not shure.
  I installed a turbo coupe proportioning valve like the swap demanded and I have the correct 87'/88' master cylinder. Whats the freakin' problem? Any help would be great.
~1988 thunderbird~
In hibernation, waiting for spring.

no pressure from brake pedal...

Reply #1 –
if the pedal pumps up it has air in it.
[SIGPIC][/SIGPIC]
1974 maverick lsx powered turbo car SOLD
1973 maverick Tijuana Taxi Tribute
1957 chevy LSX Turbo project (race car)
Owner of Joe Dirt Fabrication

no pressure from brake pedal...

Reply #2 –
Which master cylinder are you using? Which front calipers?
It's Gumby's fault.

no pressure from brake pedal...

Reply #3 –
The master cylinder is an 88' t-bird unit with a plastic tank and 1" cylinder.
The front calipers are 92' lincoln lsc units.
~1988 thunderbird~
In hibernation, waiting for spring.

no pressure from brake pedal...

Reply #4 –
did you bench bleed the master?  takes a very long time to bleed the system free of any air if the master is empty.

no pressure from brake pedal...

Reply #5 –
No pedal or soft pedal = air in system ,bad master cylinder, leak in line, leak in rubber hoses, leaks at calipers. Maybe even a bad prop valve
Hard pedal when running = bad booster.

It doesn't take to long to bleed the system without a bench bled master as long as you have a vacume or pressure bleeder. Also was the prop valve from a turbo coupe with ABS brakes? I know they can pop a relay and loose breaks.
84 Turbo coupe 2.3T Modded with 88 upper and lower intake, 88 injectors, E6 manifold, T3-4 AR.60 turbo, 31X12X3 FMIC, Homemade MBC , Greddy knock off BPV.
4 eyes see better than 2! 
Da Bird!

FreeBird

no pressure from brake pedal...

Reply #6 –
Quote from: ipsd;181119

Also was the prop valve from a turbo coupe with ABS brakes? I know they can pop a relay and loose breaks.

The proportioning valve from a TC has no relation to the relay that causes you to lose brakes. There is nothing electrical about the proportioning valve.

Air in the lines or not, that 1" master cylinder isnt sufficient for the 73mm calipers and rear disk brakes, i personally would suggest a 93 Cobra master.
It's Gumby's fault.
 

no pressure from brake pedal...

Reply #7 –
Quote from: Tbird232ci;181134
The proportioning valve from a TC has no relation to the relay that causes you to lose brakes. There is nothing electrical about the proportioning valve.

Air in the lines or not, that 1" master cylinder isnt sufficient for the 73mm calipers and rear disk brakes, i personally would suggest a 93 Cobra master.

the master cylinder was another thing I wasn't shure about. I think I'll get the cobra master cylinder.
 And yes, I did bleed the MC and It didn't seem to do much...the brake pedal had a little more "feel", but it was barely noticeable.
~1988 thunderbird~
In hibernation, waiting for spring.