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Brake booster problem??

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Old Aug 20, 2009 | 12:36 AM
  #21  
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Originally Posted by curly
What's your bleeding method? it should be:

1. pump and hold
2. open valve
3. close valve
4. repeat

It usually helps to pump the pedal a few times before holding it. You also want to do the farthest caliper from the master cylinder first. So driver rear, passenger rear, passenger front, driver front.

That new (empty) caliper is going to take some time to up, what does the line look like when you open the valve, all fluid? Lots of bubbles? Only air?


Thats exactly what I did for about three times. And the brakes were still soft like a baby's ***. Even when the pedal was pumped it wouldnt hold it feels as if the valve is open it just doesnt get any better. I checked for leaks and there are none.

I was thinking could it be the master cylinder??
Old Aug 20, 2009 | 12:38 AM
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What's coming out of the valve? You have a clear hose hooked up to it, correct? Some times you need to open the valve more than you think. If you aren't more or less solid stream of brake fluid, especially from that new caliper, I might try leaving the valve open and pumping the brakes. And of course make sure your reservoir isn't emptying.
Old Aug 20, 2009 | 12:44 AM
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Originally Posted by curly
What's coming out of the valve? You have a clear hose hooked up to it, correct? Some times you need to open the valve more than you think. If you aren't more or less solid stream of brake fluid, especially from that new caliper, I might try leaving the valve open and pumping the brakes. And of course make sure your reservoir isn't emptying.
Did that too... I left it open and pumped till fresh fluid came out, and still nothing. I looked under the car and the brake lines were fine, no damage whatsoever. Then I looked at the master cylinder and there werent leaks either.

Lets say one takes out the master cylinder, and forgets to bench bleed it, could that be the issue??
Old Aug 20, 2009 | 12:47 AM
  #24  
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yeah could be you need to pump that sucker until you actualy get some pressure hold the pressure, open the bleed valve and depress the pedal and then about half way down close the valve. And repeat eventualy your pedal will go to firm quicker and you will have the breacks you want.
Old Aug 20, 2009 | 01:14 AM
  #25  
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Ill bench bleed the master and see where that takes me
Old Aug 20, 2009 | 01:20 AM
  #26  
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also check your other lines/ calipers for issues like the one you replaced had.
Old Aug 20, 2009 | 01:27 AM
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The other the calipers and lines are fine no leaks or issues
Old Aug 21, 2009 | 08:49 AM
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It was the freaking master cylinder... I got one from Autozone, $46 with lifetime warranty, pedal went rock-hard as soon as I installed it and pumped a few time. Thanks for the help
Old Aug 21, 2009 | 11:27 AM
  #29  
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woot glad your on the raod agian
Old Aug 21, 2009 | 11:41 AM
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Originally Posted by magnamx-5
woot glad your on the raod agian
You can say that again, it was so sweet to drive the car again. goodbye metro-bus !!! lol
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