HELP i LOST MY BRAKES!!!!!!!!

HELP i LOST MY BRAKES!!!!!!!!
so.... (93 jeep XJ sport no ABS)

yesterday i drove on the highway for about an hour.. when i was exiting my park brake light came on and my pedal was mush.

2 seconds later it was alright again....

so i drove around for the past day and everything was cool.... i just drove from home again and the same thing happened... only this time the problem persists... the pedal is down to the floor, and it's hardly stopping. but it DOES feel like there is hydraulic pressure helping (not just mechanical pressure on the brake pedal.)

i looked in the manual and it says that when the light comes on, there could be a leak, or a loss of pressure. my brakes were done a year ago, with new brake lines.. i checked, no leaks.

so i took the vacuum line off the booster and my engine only reved up to 1000 RPM.
i just cleaned a buddy's throtle body and when we took his off it reved between 2500 and 3000 RPM.... so is there a vacuum problem with my POS??... brake booster?

anyone? also, i smelled the brakes burning when i got home so i sprayed them with a touch of water, and it sizzled off the front disks... what does that mean? brakes over heating?!


this is my daily driver

HELP!!!

If you were having power assist problems, the pedal would be harder, not sink to the floor. It won't set the brake light either. Check the fluid level in the master cylinder, and check for leaks. If those are fine, I would bet that you have a master cylinder gone bad (thinking that a primary cup inside of the master has gone, causing all pressure to blow past it and not go through the lines like it should). This could set off your light. Inspect your front brakes, make sure the calipers and slides aren't seizing up, to address the burning smell.

Check the fluid level in your master cylinder, if it´s at all low, the fluid went someplace. The light comes on when the braking is very unequal front to rear. Usually when a brake hangs, it´s one side or the other and noticiable when you brake hard. Some people have talked about a proportioning valve problem, that I´ve never experienced. It always turned out to be, a slight brake fluid leak someplace. When the booster messes up, you can usually hear a hissing sound, booster leaks, don´t affect pedal travel, just the pressure required on the pedal to stop.
When the rears start to leak, it collects behind the rubber dust cover on the rear wheel cylinders. Gently pull the dust cover off of the end of the wheel cylinder and see what drips out, if anything liquid comes out, it´s probably time for a new wheel cylinder.
I´ve had the fronts hang, but it always turned out to be baked on mud, a good cleaning with hot water and soap cleared it up. I´ve also had small stones jam between the front pads and the disc, but that didn´t cause any pedal problems, just a horrendous screetch. My fronts often get hot enough to blister, a finger, during normal driving. Jacking up the front and turning the tires by hand, will tell you quick if a front caliper/disc is hanging.
I´ve also had seeps at the line nuts, behind the rear backing plate and at the banjo bolts on the front calipers. A flashlight and a crawl around inspection, ´to check all the brake lines and joints, deosn´t take long and should really be done periodically anyway.

so from that i'm thinking master cylinder... the fluid level is fine, i'm gonig to jack it up and see about the calipers seizing. the rear wheel cylinders are brand new a year ago, along with pads, shoes, rear springs in the drums and all brakelines....

thanks for the info!

You have the see through master cylinder resivoir, have someone push the brakes and watch what the fluid does in the resivoir. It will move around a bit diring normal braking, but really gushes and moves around a lot (often) when the master cylinder is going bad. Don´t try it with the cap off.

my master is all metal/rust.... non see through... is there any other way to tell if that's the problem? i think it might be... but would that explain the brakes being really hot in the front?.... i assume possibly they were the only ones working properly.. therefore heating up because they were 2 out of 4 brakes stopping me?

thanks guys!, it's much appreciated!

Brake light....mushy brakes....no recent work....full fluid....sounds like a master to me.

Rev

dork said:

my master is all metal/rust.... non see through... is there any other way to tell if that's the problem? i think it might be... but would that explain the brakes being really hot in the front?.... i assume possibly they were the only ones working properly.. therefore heating up because they were 2 out of 4 brakes stopping me?

thanks guys!, it's much appreciated!

Click to expand...

If the fronts really heated up, more than likely the fluid in the front circuit boiled and you had only rear brakes -- which are not nearly as effective as the fronts. Normally, the front brakes do 2/3 to 3/4 of the work.

If your front wheels show a lot of black dust on them, that's a sign that a caliper may be hung up.

What kind of brake fluid are you using? DOT 3 has one boiling point, DOT 4 has a higher boiling point, and DOT 5 silicone has the highest boiling point. I only run silicone. (Caveat -- no two sources seem to agree on why, but you aren't supposed to use silicone brake fluid in ABS systems)

Sorry to bring this back from the dead but im having pretty much an identical problem except for the heat issue. When sitting if i hold the brake pedal down i can hear a hissing i looked and theres a little orange thing inside the rubber boot by the brake pedal. Pumping the brakes shuts off the light momentairly until i go to stop again and pedal just hits the floor. the master cylinder fluid level on one side was almost empty. Im seriously leaning towards both things are failing. this is on a 93 w/o abs.

dork said:

HELP i LOST MY BRAKES!!!!!!!!
HELP!!!

Click to expand...

Hold it , hold it, hold it.....

Let's calm down and think about this rationally ....

I guess a good place to start is:

Where was the last place you used them?




:laugh3:

so here's what happened to mine.... turned out the adjusting wheel came off and was floating around in my rear brake drum. therefore, when i pushed the pedal, the rear brakes would use all the fluid to move because they were so out of adjustment due to the wheel being broken off. the wheel floating around also damaged the wheel cylinder etc...e.tc... so i got all new brakes in the rear... problem solved!! now the brakes are better then they are in my car!

JeepZJlover said:

Sorry to bring this back from the dead but im having pretty much an identical problem except for the heat issue. When sitting if i hold the brake pedal down i can hear a hissing i looked and theres a little orange thing inside the rubber boot by the brake pedal. Pumping the brakes shuts off the light momentairly until i go to stop again and pedal just hits the floor. the master cylinder fluid level on one side was almost empty. Im seriously leaning towards both things are failing. this is on a 93 w/o abs.

Click to expand...

Which chamber of the master cylinder is low? One is for the front brakes, the other is for the rear. You start looking for problems in the circuit that's losing fluid.

Eagle said:

Which chamber of the master cylinder is low? One is for the front brakes, the other is for the rear. You start looking for problems in the circuit that's losing fluid.

Click to expand...

yup, i second this... if it's something like a rusty brake line, it's a pretty easy fix. most auto shops carry flared lines that you just have to screw together in place of the old ones! hopfully this is your only problem.