?s about brake system.

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Aug 3, 2004 | 09:08 PM

Stampede

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From: Oh

?s about brake system.

I have a 86 Mustang Gt 5.0L, auto. I put new front rotors and pads on the front, the rear shoes look good. I think my problem is that the brake pedal goes about half way to the floor and makes a hissing noise. My question is, how can I till if I have a problem with the brakes? I not sure if the car has always been like this, or what. I have owned the car for about 11 yrs, I just haven't driving it lately.
Thanks Stampede

Aug 3, 2004 | 09:56 PM

F2504x4

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From: On the road in Ohio

vacum booster? and do they grab or the pedal not return? also are you sure that all the air has been bleed out? they pump up and get hard {air in system} hissing ...that sounds like a booster to me . leaky master cylinders can ruin the boosters

on edit: are the rear brakes adjusted?

to test the the booster, start the car, shut off after a minute, wait 2-3 minutes then remove the vacum line at the booster carefully, you should still hear a vacum hiss. if it does then its holding vacum.

Last edited by f=2504by497; Aug 3, 2004 at 09:59 PM.

Aug 3, 2004 | 10:40 PM

Stampede

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From: Oh

That's what I thought, the vacum booster. Yeah, it goes down about half way then they start grabbing, pedal does return. Yes I have bleed the lines, no air. To adjust the rear brakes, I have to back up, pump the brakes, then back, pump brakes, ect... Correct? And they will not pump up.
What do you have to watch for, when removing and installing a new booster, I have taken them, when gutting a couple of mustangs, now I wish I would have kept those vacum boosters.

Thanks f=2504by497
you rock man.

Aug 3, 2004 | 10:52 PM

F2504x4

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From: On the road in Ohio

i'm thinking that the rear brakes "might be still out of adjustment,
to adjust them ....pull the rear drums on the bottom inbetween the brake shoes is the adjuster wheel, make sure the it is clean and turns, when you turn that wheel it spreads the brake shoes apart.....now adjust it till you can just barely fit the brake drum back on....and yet the drum will still turn barely , that should make a differance. and you can also do this by the slot on the backside of the backing plate, there is a slot on the bottom . about 1" x 1/4 wide, usually has a rubber plug in it.
but have the wheel off the ground when doing this.so that you can tell when its adjusted.
on edit:you can use a straight blade screwdriver to do this, but a brake adjusting tool works better.............
how did you bleed the master cylinder?

Last edited by f=2504by497; Aug 3, 2004 at 11:15 PM.

Aug 3, 2004 | 10:52 PM

wlihntr

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From: colorado

Quote:

Originally Posted by Stampede

To adjust the rear brakes, I have to back up, pump the brakes, then back, pump brakes, ect... Correct

Thanks f=2504by497
you rock man.

you have to adjust them if you put new shoes on them or had them apart.(just backing up wont do it) the auto adjustment works only after they have been properly adjusted

Aug 3, 2004 | 11:01 PM

F2504x4

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From: On the road in Ohio

Quote:

Originally Posted by wlihntr

you have to adjust them if you put new shoes on them or had them apart.(just backing up wont do it) the auto adjustment works only after they have been properly adjusted

correct

i forgot about that

also re-read my post , i added to it.

Aug 4, 2004 | 07:42 PM

Stampede

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From: Oh

I checked the vacum booster, by letting the engine run for a few minutes, then removing the vacum line, after shutting off the engine. No hissing, pulled off vacum line when car was running, plenty of vacum. Then I checked the brakes with the line disconnected, a big difference. Pedal felt firm, very firm, but as soon as I stepped on the pedal, it was firm and stiff.
Can I check the booster with a vacum gage, by creating a vacum and seeing if it holds vacum?
I will try to adjust the rear brakes, tomorrow or so, I have never adjusted them.

Thanks Stampede