Hey dudes, and gals,
Just went for the full disc brake conversion and system upgrade.
First easy question:
Is anyone running an FJ80, non-ABS, Master cylinder, and FJ80 Brake booster, and getting a solid pedal while the engine is running???????
The rest of the story...
-New FJ80 non-ABS Brake Master cylinder
-New FJ80 Brake Booster
-New rear discs, using Monte Carlo calipers
-New front calipers, using Wilwood 4 piston calipers. (replaced old Wilwoods)
-new rear proportioning valve.
-all new flex lines except the two front steel braided lines that appear fine.
I cannot get, for the life of me, a solid brake pedal while the engine is running. I will slowly sink to ..almost.. the floor. With engine off, the pedal is rock solid at the top. ..start the motor and it will travel half way down, and slowly sink almost to the floor.
***Big clue***
with the flex lines to the axles clamped off, the brake pedal is solid, with the engine running.
-Bench bled master cylinder
-I have bled the bejezus out of the system, engine running and not. used a brake bleeding container with a check valve. Also gravity bled, trying to get any last bubble out of there. I've put over a couple quarts through there so far...
-Adjusted the pedal for maximum travel.
-Adjusted the brake booster rod to specs. Then adjusted it out further and further, trying to get some pedal. Currently the booster is depressing the M/C slightly at rest. It helped...
-Rotated the front calipers vertically to get every tiny bubble out of there.
It appears the residual pressure valves are working. All brake pads are lightly dragging the rotors and evenly spaced.
Also, about to rebleed the M/C, but hesitant to open the system back up.
Also about to swap the stock booster back in to see if I'm getting too much brake assist.. That's all I can think of right now!
I'm am wondering if the FJ80 M/C is providing sooo much boost the pedal WILL travel to the floor if you stand on it?
So back to my original question.. Is anyone getting a solid pedal while using an FJ80 MC and booster???
Holy cow I'm stumped.
Any help?
Thanks, B.
Just went for the full disc brake conversion and system upgrade.
First easy question:
Is anyone running an FJ80, non-ABS, Master cylinder, and FJ80 Brake booster, and getting a solid pedal while the engine is running???????
The rest of the story...
-New FJ80 non-ABS Brake Master cylinder
-New FJ80 Brake Booster
-New rear discs, using Monte Carlo calipers
-New front calipers, using Wilwood 4 piston calipers. (replaced old Wilwoods)
-new rear proportioning valve.
-all new flex lines except the two front steel braided lines that appear fine.
I cannot get, for the life of me, a solid brake pedal while the engine is running. I will slowly sink to ..almost.. the floor. With engine off, the pedal is rock solid at the top. ..start the motor and it will travel half way down, and slowly sink almost to the floor.
***Big clue***
with the flex lines to the axles clamped off, the brake pedal is solid, with the engine running.
-Bench bled master cylinder
-I have bled the bejezus out of the system, engine running and not. used a brake bleeding container with a check valve. Also gravity bled, trying to get any last bubble out of there. I've put over a couple quarts through there so far...
-Adjusted the pedal for maximum travel.
-Adjusted the brake booster rod to specs. Then adjusted it out further and further, trying to get some pedal. Currently the booster is depressing the M/C slightly at rest. It helped...
-Rotated the front calipers vertically to get every tiny bubble out of there.
It appears the residual pressure valves are working. All brake pads are lightly dragging the rotors and evenly spaced.
Also, about to rebleed the M/C, but hesitant to open the system back up.
Also about to swap the stock booster back in to see if I'm getting too much brake assist.. That's all I can think of right now!
I'm am wondering if the FJ80 M/C is providing sooo much boost the pedal WILL travel to the floor if you stand on it?
So back to my original question.. Is anyone getting a solid pedal while using an FJ80 MC and booster???
Holy cow I'm stumped.
Any help?
Thanks, B.
Last edited: