Y u no bleed?


  • Y u no bleed?

    Hey guys. I've bled brakes on several cars before this one, but I can't seem to get this car to fucking cooperate. Everything is new on the car, aside from the power brake booster. I've gone through 3 calipers from RockAuto that were leaking, but the one i currently have isn't. I just can't figure out what is going on. I can visually see with the bleed valves open and a tube hooked into a bottle of brake fluid, that the air has been pushed out of the line. I'm starting at the Driver's side rear caliper and working my way around toward the master cylinder. I've also bled the master cylinder (it's new Beck/Arnley) and have even replaced the bleeder screws for good measure.

    There is no brake pressure, until after it's been pumped 3-4 times. Wait a few seconds, the pressure is gone. Could this be a brake booster failure, or perhaps the master cylinder is also faulty?

    I'm fed up, but open to advice. Who knows, maybe I just need to attempt with two people
    " I spend another hour trying to rip the bolt out of the subframe, pausing every five minutes to scream and contemplate how I get myself into these situations. Two cars over, a guy urinates. I watch the steam waft off of the fresh puddle in the gravel. It merges with the blowing snow and is cut by the aerodynamic wedge of a nearby Fiero. Beautiful. Another pry and the carrier finally falls to earth. I walk out of there $80 lighter, which makes me more mad." - Brian Kolar

  • #2
    If u are doing urself, a set of speed bleeders can make the process MUCH easier.
    Butter (credit where credit is due): "You have this "gift" where you can make cooking a Hot Pocket seem like you need a certain wavelength microwave and involve brown mustard."

  • #3
    When I say new:

    New mastery cylinder
    New SS hoses everywhere
    New rear calipers
    New lines in places, and new rotors/pads everywhere.
    " I spend another hour trying to rip the bolt out of the subframe, pausing every five minutes to scream and contemplate how I get myself into these situations. Two cars over, a guy urinates. I watch the steam waft off of the fresh puddle in the gravel. It merges with the blowing snow and is cut by the aerodynamic wedge of a nearby Fiero. Beautiful. Another pry and the carrier finally falls to earth. I walk out of there $80 lighter, which makes me more mad." - Brian Kolar

  • #4
    Ordered a new brake booster. I've come to the conclusion that it's the brake booster because a) I have $123. b) what's another $123 at a car that has over $2400 of new parts on but is only worth $1400. c) if nothing is leaking, and everything is bled, why else would the pedal fall to the ground? Vacuum leak?
    " I spend another hour trying to rip the bolt out of the subframe, pausing every five minutes to scream and contemplate how I get myself into these situations. Two cars over, a guy urinates. I watch the steam waft off of the fresh puddle in the gravel. It merges with the blowing snow and is cut by the aerodynamic wedge of a nearby Fiero. Beautiful. Another pry and the carrier finally falls to earth. I walk out of there $80 lighter, which makes me more mad." - Brian Kolar

  • #5
    Hate to tell you its not the booster.

    All the booster does multiply how hard you press down on the brake pedal.

    A bad booster is gonna make it really hard to press down on the brakes. It would be like pressing on the brakes with the engine off.

    You did bench bleed the master cylinder right?

    It sounds like you still have a lot of air in the system

    I'm a fan of using a pneumatic vacuum setup to bleed t he brakes. The cheesy hand held vacuum pumps just don't produce enough vacuum volume and I get frustrated using them.
    Life's short
    Go fast
    Have a blast
    Leave a good looking corpse

  • #6
    Hardest part is bench bleeding the master cylinder. After that just keep fluid in it while you bleed each corner, starting at the furthest away.
    '85 300zx turbo: exhaust, intercooler, coilovers, etc…SOLD, will be missed
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    '97 Dodge 2500: 12v Cummins …selling and will be missed
    '94 Jeep Cherokee: D60 Front 14b rear, both locked and 5.38 gears, 37" mtr's
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  • #7
    I'm hearing you both here. I've bled the master cylinder off the car, and on the car, using short lengths of brake lines fed back into the resv to ensure the fittings aren't sucking in air. I also tried a siphon air-gun. Cracking open each bleeder with the siphon on the bleeder. That worked amazing for the clutch slave cylinder, but no luck on the brakes. Also, point the gun in a rag, or you will risk spraying a mist of brake fluid all over the place lol.

    I did have the car on, and when I pumped the brakes a few times, it would stall. That sort of made me suspect a vacuum/seal leak within the booster, as the plunger area was NASTY when I removed the original master-cylinder. I cleaned it up, but maybe it damaged a seal.
    " I spend another hour trying to rip the bolt out of the subframe, pausing every five minutes to scream and contemplate how I get myself into these situations. Two cars over, a guy urinates. I watch the steam waft off of the fresh puddle in the gravel. It merges with the blowing snow and is cut by the aerodynamic wedge of a nearby Fiero. Beautiful. Another pry and the carrier finally falls to earth. I walk out of there $80 lighter, which makes me more mad." - Brian Kolar

  • #8
    I've moved onto replacing the power brake booster, and one more caliper. I also took the master off the car, bled it again, then put it on the car and bled it there (no air came out once on the car as well). The old booster did have brake flood by the plunger-thing, and although the pedal is somewhat improved, still not happy. When my roomie gets back in town, I'll try bleeding with two people again. If that doesn't work, maybe the new master is a faulty master cylinder somehow? I'm so stumped. How could a system not be leaking fluid, but keep gaining air.
    " I spend another hour trying to rip the bolt out of the subframe, pausing every five minutes to scream and contemplate how I get myself into these situations. Two cars over, a guy urinates. I watch the steam waft off of the fresh puddle in the gravel. It merges with the blowing snow and is cut by the aerodynamic wedge of a nearby Fiero. Beautiful. Another pry and the carrier finally falls to earth. I walk out of there $80 lighter, which makes me more mad." - Brian Kolar

  • #9
    I always had problems bleeding the Z. 1 person or 2 person I could never gain the pedal pressure or get all the air out. I caved in and purchased a vacuum assist bleeder. No problems since then.

    It doesn't make sense, but it works and no more headaches.
    86na - BlueZ
    Shiro #366 - Kouki Monster
    85t - Mr Tickles

  • #10
    Any suggestions Adam? I'd rather buy a bleeder than take it to a shop. At least I'll still have my pride! lol
    " I spend another hour trying to rip the bolt out of the subframe, pausing every five minutes to scream and contemplate how I get myself into these situations. Two cars over, a guy urinates. I watch the steam waft off of the fresh puddle in the gravel. It merges with the blowing snow and is cut by the aerodynamic wedge of a nearby Fiero. Beautiful. Another pry and the carrier finally falls to earth. I walk out of there $80 lighter, which makes me more mad." - Brian Kolar

  • #11
    Mityvac vacuum assist is the bees knees if you pony up and bleed anything regularly.

    Rather if its just once a year head over to Harbor Freight and just get a hand pump. Anything really that will pull a vacuum, just ensure your BMC doesnt run dry.

    I have used both on the Zs with favorable results. I dont know what it is but bleeding the brakes on z31 is my kryptonite --> vacuum assist has been the only way for me to win the battle.
    86na - BlueZ
    Shiro #366 - Kouki Monster
    85t - Mr Tickles

  • #12
    I purchased the M800 MityVac unit, took it out of the box, didn't build pressure or create vacuum lol. So I returned it for the cheaper $20 Pittsburgh one, and it works! I'm going to try it out tonight after dinner, and if I have brakes tonight, EVERYONE ON THE FORUMS GETS A FREE KISS. FROM ME!
    " I spend another hour trying to rip the bolt out of the subframe, pausing every five minutes to scream and contemplate how I get myself into these situations. Two cars over, a guy urinates. I watch the steam waft off of the fresh puddle in the gravel. It merges with the blowing snow and is cut by the aerodynamic wedge of a nearby Fiero. Beautiful. Another pry and the carrier finally falls to earth. I walk out of there $80 lighter, which makes me more mad." - Brian Kolar

  • #13
    So this thing rocks. However, now I can visually see, my issue is somewhere on the driver's rear. I've already replaced this caliper THREE TIMES, because of a faulty A-1 caliper (it was leaking at the piston seal), but no leaks currently. The hard-line on the control arm has a really funky bend that could be trapping air? Everything after that 3-way block is new on both sides.
    " I spend another hour trying to rip the bolt out of the subframe, pausing every five minutes to scream and contemplate how I get myself into these situations. Two cars over, a guy urinates. I watch the steam waft off of the fresh puddle in the gravel. It merges with the blowing snow and is cut by the aerodynamic wedge of a nearby Fiero. Beautiful. Another pry and the carrier finally falls to earth. I walk out of there $80 lighter, which makes me more mad." - Brian Kolar

  • #14
    Glad to see the vacuum assist worked out. z31s hate manual brake bleeds
    86na - BlueZ
    Shiro #366 - Kouki Monster
    85t - Mr Tickles

  • #15
    It's seriously the best dude. I could've saved SO MUCH trouble/brakefluid if I had used this from day one lol. Thanks!
    " I spend another hour trying to rip the bolt out of the subframe, pausing every five minutes to scream and contemplate how I get myself into these situations. Two cars over, a guy urinates. I watch the steam waft off of the fresh puddle in the gravel. It merges with the blowing snow and is cut by the aerodynamic wedge of a nearby Fiero. Beautiful. Another pry and the carrier finally falls to earth. I walk out of there $80 lighter, which makes me more mad." - Brian Kolar