Ok my husband spent 10 hours working on his truck today and is very frustrated. His truck was parked for about 4 months, before that it was fine, he started it up one day and he had no brakes at all. His brakes went out and him and a friend identified it was the proportional valve after going through everything and trying to trouble shoot it, so we got a new one and he installed it. Before installing the new proportional valve It was not sending any brake fluid to the back but it was going to the front. He then bled the brakes, over and over and over after the new installation.... He bled everything, all valves and they still go to the floor. He is bleeding them in the sequence he is supposed to, the master cylinder is functioning properly. When he gravity feeds the back ones only a little fluid comes out, there are no leaks in any of the lines either. Somehow he can't get the air out of these lines and he swears this is what it has to be. What else can he do? the only work he had done to it recently was installed a new power steering line that had a bad leak, that is when everything started happening and he has had a vacuum leak for a while...can either of those things have anything to do with this? I know that sounds stupid but we are trying to hit all aspects of this. Thanks for any help you can give to us.
How did you come to the conclusion that the master cylinder is ok? Does the level of brake fluid in the MCyl. rise & fall while pumping the brakes. I feel no fluid is entering the chamber which has the piston. This piston is directly connected with the brake pedal.Have it checked and the oil seal in it too.....sodeep
Hello, and this can be several things. First off you need to check your hydro-boost. To do this pump the brakes while the engine is off until the brakes become hard the start the engine. If the pedal sinks and then comes back up your hydro-boost is working. If they sink and do not "kick back" a little bit you may have a problem in your power steering. Did you bleed the power steering system whin you installed the new power steering line. To bleed your power steering jack up the front of your vehicle and put it on jack stands and always remember proper jackstand placement and jack procedures and wear eye protection while under a vehicle. Once the vehicle is jacked up, raise the wheels off the ground top off fluid then:
Turn the wheels lock to lock 10 times with engine off
Lower car, top off fluid
Start car and trun the wheels lock to lock 10 times
Top off fluid
Any air left in there should bleed out in 6-12 miles of driving
Now before you go this far make sure all your power steering hoses and clamps are not leaking and tight.
If your proportioning valve has been replaced there is a safety valve inside that shuts off fluid to your back brakes if they are not working. This valve can be reset by removing a plastic cover on the front of it and reseting the valve or you can step on the brakes real hard and a audible pop should be heard and this is the valve resetting. You should also check how your disc brakes are adjusted in the back because the wheel cylinders can bring in air through them. The master cylinder also is a device that needs to be bled. Axle bearings hold the wheel to the axle and leak fluid around the inside of the wheel causing an air leak as well. I would go over your intire brake system and chase and follow all brake lines, calipers, and brake components to see if any ae leaking. If all else fails get a repair manual for your vehicle and use the troubleshooting guide in it. If you have any other questions just ask me and I hope this solves your problem for you!
If the master is fine and there is no air in the master cylinder, ABS block, and the proportioning valve. Then I would guess that a brake line to the rear brakes is damaged, pinched, or clogged. Dodge has had problems with the high pressure brake lines. The steel clamp around the line gets rusty and squeezes the high pressure hose closed. Also check the bleeders on the rear brakes, not sure if something was overlooked.
IF THE MASTER CYL WENT DRY DURING REPAIRS, YOU NEED TO BLEED THE MASTER CYL FIRST. MAKE SURE THE BLOCK OFF VALVE IN THE PROPORTIONAL VALVE IS RESET. TRY REMOVING THE REAR BLEEDERS COMPLETLY AND SEE IF YOU THEN GET FLUID GRAVITY BLEEDING. IT IS ALSO A GOOD CHANCE THAT WHILE SITTING PARKED FOR THAT LONG THE WHEEL CYLS MAY BE FROZEN. ALSO IF YOU CANNOT BLEED THE MASTER IT IS BAD.
SOURCE: 98 Dodge Ram 1500 brakes go completely to the floor.
It could very well be air bound, those lines to the rear brakes are the longest in the truck. Especially if he's getting a little fluid out by gravity bleeding it. My advise is to get a vacuum bleeder kit. I got mine from an auto parts store, it honestly cost me 25 dollars, and it's a gift from God! Instead of trying to push the fluid, your sucking it out from the wheel. Works beautifully, especially if your truck has anti lock brakes.
SOURCE: brakes wont come up
sounds like a bad diaphragm in your brake booster. listen for air while running at booster , disconnect vacuum hose depress pedal if it is good there should be a big difference in pedal
SOURCE: 1997 GMC Sierra 5.7 changed master cylinder
check under your master cylinder,is there another clyinder below with one line in and one line out,if you do I found this is for the Abs to the rear,I had to replace this it was full of air,and did exactly what yours is now
SOURCE: how do u bleed brakes on 1995 mercury sable?cannot
lots of the new cars needs pressure to be bled and also a computer to go in to brakes to open up the valves please contact you dealer
9,047 views
Usually answered in minutes!
what is the best way to bleed the brakes on a dodge 1995 sst 1500 ram. first off. my brakes were fine, I let it sit for 4 months and the ab and brake like came on. I replaced the proportional valve and both lights went out I feel this was the problem. so how do I bleed these brakes. Kevin
how do I flush the brake lines
this morning I bleed the master cylinder by connecting a hose frome the outlets and running them into the brake reservoir until I got a steady flow of brake fluid. one of the things that concern me now is that when I pump the brakes the reservoir rises up and down. If i stomp on the brakes and the cap is off it will blow brake fluid out of the cylinder
How can we check the master cylinder to make sure it is ok, We put hoses on the master cylinder and fed it back into the resovoir......one flowed fine the other one as you are pumping the brakes nothing came out of it.
Well we decided to sink more money into it and replaced the master cylinder, we then re-bled the brakes and we now have brakes, atleast we will not take out any more trees in the yard! Thanks for everyone that helped out.
I know this has been a while but please tell me how you fixed it mine is doing the same thing, I've stumbled across this! I've tried everything and my truck is doing the EXACT same thing PLEASE!
×