brake issues continued
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Car: 86 Trans Am
Engine: 305 LB9
Transmission: 700r4
brake issues continued
Hey guys,
Long story short my master cylinder cap had a crack since I've had the car. I finally bought an aftermarket cap and gasket and replaced it and bled the system all 4. 4 way discs. The car stops better but when the pedal goes too far the brake light comes on until I push the pedal down far again
I'm now looking to the prop valve. There are no leaks and it looks good but it could be malfunctioning. What else could be an issue?
I may replace the prop valve , but what else could be causing it to stop slowly (can't lock up brakes but I can pump for more pressure)?
Thanks! I'm just trying to get this junk to stop pretty decent and not cause a brake light. And yes the pads are almost new, rotors are flawless, and wiring under dash looks good
Long story short my master cylinder cap had a crack since I've had the car. I finally bought an aftermarket cap and gasket and replaced it and bled the system all 4. 4 way discs. The car stops better but when the pedal goes too far the brake light comes on until I push the pedal down far again
I'm now looking to the prop valve. There are no leaks and it looks good but it could be malfunctioning. What else could be an issue?
I may replace the prop valve , but what else could be causing it to stop slowly (can't lock up brakes but I can pump for more pressure)?
Thanks! I'm just trying to get this junk to stop pretty decent and not cause a brake light. And yes the pads are almost new, rotors are flawless, and wiring under dash looks good
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Car: 91 formula ws6
Engine: 355 tpi OBDII
Transmission: 4l60E
Axle/Gears: 2.73 with 4th gen brakes
I second the still air in lines. How did you bleed it? Was it run dry then bled traditionally from all fours? Did you end up bleeding the master separate? I've seen them become air bound is why I ask.
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Car: 86 Trans Am
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Re: brake issues continued
I bled farthest from the master and inwards and didn't bleed it dry. Pumped it up, bled out the air filled fluid and closed it off. Topped off master and onto another brake
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Car: 91 formula ws6
Engine: 355 tpi OBDII
Transmission: 4l60E
Axle/Gears: 2.73 with 4th gen brakes
Damn, was hoping you ran it dry at some point and maybe my question could have been of some help. If it was air filled, it could have gotten a little air bound tho?
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Re: brake issues continued
I'm not sure about that, it seems good. I'm nearly a 100% sure the master cylinder needs to be bled. With a broken cap for that long it makes sense
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Car: 91 formula ws6
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Worth a shot I'd imagine. Or just keep on pumping and holding. Lol. I had a trailblazer the other day do this but, I ran the master dry after the first caliper. Fluid was nasty...
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Re: brake issues continued
Can't bleed the MC installed on the car.
It's at such an angle that the fitting for the line isn't at the highest point. IOW, a certain amount of air, once it's in there, can NEVER be bled out. It just stays up there at the top.
Gotta "bench bleed" it. Which can be done with it somewhat on the car; take the nuts off that hold it on, move it forward enough that it can sit closer to level, take the cap off, have your assistant poke with very short strokes at the piston with something non-metal (so you don't chew it up) until air quits coming out of the holes at the bottom of the reservoir.
It's at such an angle that the fitting for the line isn't at the highest point. IOW, a certain amount of air, once it's in there, can NEVER be bled out. It just stays up there at the top.
Gotta "bench bleed" it. Which can be done with it somewhat on the car; take the nuts off that hold it on, move it forward enough that it can sit closer to level, take the cap off, have your assistant poke with very short strokes at the piston with something non-metal (so you don't chew it up) until air quits coming out of the holes at the bottom of the reservoir.
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Car: 86 Trans Am
Engine: 305 LB9
Transmission: 700r4
Re: brake issues continued
Can't bleed the MC installed on the car.
It's at such an angle that the fitting for the line isn't at the highest point. IOW, a certain amount of air, once it's in there, can NEVER be bled out. It just stays up there at the top.
Gotta "bench bleed" it. Which can be done with it somewhat on the car; take the nuts off that hold it on, move it forward enough that it can sit closer to level, take the cap off, have your assistant poke with very short strokes at the piston with something non-metal (so you don't chew it up) until air quits coming out of the holes at the bottom of the reservoir.
It's at such an angle that the fitting for the line isn't at the highest point. IOW, a certain amount of air, once it's in there, can NEVER be bled out. It just stays up there at the top.
Gotta "bench bleed" it. Which can be done with it somewhat on the car; take the nuts off that hold it on, move it forward enough that it can sit closer to level, take the cap off, have your assistant poke with very short strokes at the piston with something non-metal (so you don't chew it up) until air quits coming out of the holes at the bottom of the reservoir.
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Re: brake issues continued
Did they "bench bleed" the MC?
If not, the air that was in there before, is still there.
If not, the air that was in there before, is still there.
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