92 3.9 LE A/T 2wd.So yesterday I started having trouble with my brakes.Pedal was going to the floor before they would engage or I had any brake at all.Checked the master cylinder and it was near empty.Filled and checked for leaks from one end to the other,found nothing.Lost at where it could have gone.I figured it was the master after filling and bleeding,still nothing.Today I changed the master filled bleed and nothing.I also have VERY little fluid going to the rear right(That is the one I started with but stopped there)still have no brakes.Im thinking plugged? Maybe? Then again never owned a vehicle wich had this happen.Only other issue I can think of is booster.There is very loud air sound inside when I press the breaks.Then again,it has always done this since I owned it but really never noticed if it is louder now.Just looking for issues I could check on before I spend too much money on this project wich was not needed.Ty

 

how was it bleed? this requires 2 people

one to pump brakes and hold .... other to bleed..

 

Have a look at the proportioning valve.

 

Thanx guys.First yes there where 2 of us doing the bleeding as you described.Second,what am I looking for as far as the proportioning valve goes? How will I know its faulty?

 

Check out this thread.

 

You can bleed the brakes alone. You need a bottle that will stand on its own. You drill a hole in the top the just under the right size for a hose that will fit tightly over the nipple on the bleeder valve. That way the hole is tight around the hose and does not allow in air. If you need to use clay or JB weld to seal it to the cap. Make the hose long enough to reach the bottom of the bottle and fill the bottle enough to cover the end of the hose a couple inches.
Then you put the free end on the nipple and open the bleeder valve. Open the master cylinder and make sure it is full and cover it. Then pump the brakes gently all the way down and back up, several times. Then check the bottle you should see discolored fluid from the system. Remember to close the valve before removing the hose to go to the next wheel.

Do this on both sides then test them for feel before trying to drive it. I changed my front pads, rotors, bearings and calipers and this is how I bled them on my own. They work fine no probs.
EDIT- Do not forget to check the master cylinder is filled as you proceed.

 

If there's no problem with the proportioning valve (leaking or something), you may have a leaking right rear wheel cylinder (since you say that's getting no fluid). Pull the drum off and look for moisture on the backing plate.

 

First to all who replied ty so much.I changed out my master cylinder to no avail.Then upon reading an article about the booster found I wasn't supposed to hear air under the dash when pushing the pedal.I took it out and it was JUNK.Even looked bad def the original.Changed that put my new booster on bleed the system and I have better brakes now than when I first got this truck..

 

That's great news, 1stG92.

Now - what !I! do is use one of these and do a full flush of the brake fluid.

The "low fluid flow", if it persists after the booster swap, may be due to bad brake hoses collapsing internally. Or it may be that it was the booster and you can peg someone 25' the other side of the car when you go to bleed now *grins*

But due to age, I'd be saving up and buying the rubber hoses as I could, then swapping them in a swap job (complete with a full flush - I'm paranoid, I go through about a gallon of brake fluid on a flush!) one long weekend.

Do invest in some PBlaster or Kroil or your favorite penetrating fluid, and hose down all the hose fittings. Be prepared to replace the hardline ends (probably won't need to, but better to have the flare fittings and not need them then need them and not have them!)

Also, again due to age and how paranoid I am with brakes, I'd look at replacing the master cylinder also.

That's all paranoia and because I really, Really, REALLY hate Aloyisius Murphy and his cousin, Justin Case, both.

RwP