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Old 05-28-2008, 11:18 PM   #1
stanglifemike
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HELP!! Brakes went out!!

The pedal is just going to the floor now. I've always had pump it some, and some times at a redlight, the pedal would go to the floor after a minute or so, and I would have to repress the brake pedal and all was well. Yeterday though, on the way home I had nothing. I was near the neighborhood so I was able to get it home and into the backyard. I pulled the front wheels and loosened the line at the caliper. I had my daughter push the brake pedal and fluid was coming out just like it should. So, do you think its my calipers? What are the chances of both front calipers going out at the same time though?? Could it be the booster? Please help, and thanks for any thoughts
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Last edited by stanglifemike; 05-28-2008 at 11:19 PM.
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Old 05-28-2008, 11:39 PM   #2
michael bustamante
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Re: HELP!! Brakes went out!!

sounds like the master cyl. to me. those are all the symptoms
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Old 05-28-2008, 11:43 PM   #3
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Re: HELP!! Brakes went out!!

So brake fluid would be going to the calipers even though the master cylinder went out?
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Old 05-28-2008, 11:50 PM   #4
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Re: HELP!! Brakes went out!!

If your brake fluid is at normal capacity, I would suspect the master-cylinder.
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Old 05-28-2008, 11:51 PM   #5
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Re: HELP!! Brakes went out!!

Brake fluid under no pressure would still flow from the master cylinder. Once resistance is met in a pressurized system, the fluid pressure will just balance in the MC. (no pedal)
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Old 05-28-2008, 11:51 PM   #6
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Re: HELP!! Brakes went out!!

You need to step back and look over the whole system.
Park it on dry pavement if you can.
Check the master clylinder... is it full... on both halfs?
When you top it off (I'm gonna assume 1/2 of it is bone dry) and pump the pedal, do you hear fluid splattering?
Are you seeing any puddles forming?
look on the back side of your tires... are any of them wet?

There's a LOT more to it than calipers up front and a master cylinder, and any guesses with what little info you gave us... is nothing more than a guess.

Your initial problem;
Quote:
I've always had pump it some, and some times at a redlight, the pedal would go to the floor after a minute or so, and I would have to repress the brake pedal and all was well.
only indicates having a little air in the system. So this new problem, is a new problem.
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Old 05-28-2008, 11:51 PM   #7
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Re: HELP!! Brakes went out!!

"Usually" when a MC goes 'out' it is bypassing fluid around the piston in the MC.If that is what's happening then the fluid will flow out the line or bleeder.This is because the fluid will flow thru the path of least resistance.If you want a sure check you will need to hook a pressure guage to the system.
If you had no brakes then your rears are also not working.
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Old 05-28-2008, 11:52 PM   #8
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Re: HELP!! Brakes went out!!

OK cool, thanks for the quick responses guys!! Is it simple to swap out, or anything tricky I should look for. Any special tools, etc..
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Old 05-28-2008, 11:53 PM   #9
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Re: HELP!! Brakes went out!!

Simple but be sure to bench bleed it to get the air our before you install it.
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Old 05-28-2008, 11:54 PM   #10
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Re: HELP!! Brakes went out!!

How do you bench bleed ??
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Old 05-28-2008, 11:56 PM   #11
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Re: HELP!! Brakes went out!!

By the way, I put new pads and rotors on the front about 10 months/1500 miles ago
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Old 05-29-2008, 12:00 AM   #12
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Re: HELP!! Brakes went out!!

Quote:
Originally Posted by Longhorn Man View Post
You need to step back and look over the whole system.
Park it on dry pavement if you can.
Check the master clylinder... is it full... on both halfs?
When you top it off (I'm gonna assume 1/2 of it is bone dry) and pump the pedal, do you hear fluid splattering?
Are you seeing any puddles forming?
look on the back side of your tires... are any of them wet?

There's a LOT more to it than calipers up front and a master cylinder, and any guesses with what little info you gave us... is nothing more than a guess.

Your initial problem;

only indicates having a little air in the system. So this new problem, is a new problem.
Back half of MS was almost empty, first thing I did was top it off. No splattering and no puddles forming. No wet tires
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Old 05-29-2008, 12:01 AM   #13
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Re: HELP!! Brakes went out!!

Long shot, but one time I had a simular problem and I changed the MC and it did not help any. It turned out to be just the vac. gromet the goes into the booster.
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Old 05-29-2008, 12:09 AM   #14
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Re: HELP!! Brakes went out!!

a vac grommet on a booster shouldn't cause the pedal to go to the floor, it should cause a rock hard pedal that is hard to move down at all.

The rear portion of the master cylinder was empty, and there is no evendence of fluid anywhere?
You probably are looking at a bad master cylinder.
but there's bad news here too.
If you have power brakes, then all that fluid went in the booster, where it is now eating the rubber lining of the diaphram. It will end up popping the booster.
You can run it, but I would recomend getting it replaced. I personally lost an engine due to the instant lean condition when my booster popped.
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Old 05-29-2008, 12:22 AM   #15
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Re: HELP!! Brakes went out!!

thanks for the heads up!!
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