Rear Brake issues( Drums )

[2003Xtreme]

Well long story short I have put all new brake lines on the rear of my truck and bled them. All the front brakes are brand new and have been previously bled. When you push the pedal down as if you were bleeding the brakes, it never gets real stiff, but sometimes it gets somewhat hard. When you released the bleeder screw on the back brakes, the pedal does not go down like it normally does on anything else I have done. There is good steady stream of fluid coming out of the screws. The leaks that the truck had on the rear have been fixed. It is not leaking brake fluid anywhere that I am aware of. So anyways.. lol when the truck is running, you have to pump the brakes up to really get that much of a pedal. They still work for the front decent, but the back ones take alot of pumping of the pedal to even get it to begin to grab the wheel. I am not sure if it is the master cylinder/ brake booster/ or proportioning valve going bad. I have heard a brake booster leak because they loose vacuum and mess with the motor idle, but not the case here. any help I would appreciate it.

 

[Wagonbacker9]

sounds like you still have air in the lines to me.

 

[2003Xtreme]

thats what I thought! still no pedal though. Prolly need to bleed them all the way around starting at furthest point and see what happens. Another question.. that rubber gasket that is in the master cylinder under the cap.. what purposed does it serve?

 

[Wagonbacker9]

thats what I thought! still no pedal though. Prolly need to bleed them all the way around starting at furthest point and see what happens. Another question.. that rubber gasket that is in the master cylinder under the cap.. what purposed does it serve?

As opposed to what? That should always be the bleed procedure.

And I'd imagine its purpose is to keep fluid in the resevoir.

 

[outalne94z71]

if the rear shoes are not snugged up properly you will get a low petal, so make sure those are setup properly first

 

[2003Xtreme]

I was not saying opposed to any other way just stating the fact that is how I do it to inform you that I know to start at furthest point to rule out the option that I am not bleeding them correctly. Also I did not know if that gasket inside the resevoir needed to hold vacuum or suction because everytime I take that cap off the MC it has fallen down inside a little bit. It needs replaced, but it was just a thought I had.

 

[outalne94z71]

if you gently clamp all 3 brake hoses with a vise grip, you can remove one at a time and press the petal to find where it drops the worst(only have 1 clamp off at a time), that is where the problem is, all 3 clamped should give you a high rock hard petal, if not then you have a master issue.

 

[Swims350]

GOOD LUCK!!!!!!!!!!!!!

I got the exact same crap right now, still no pedal. I got new wheel cylinders, lines, hoses, pads, shoes, calipers, all that crap mine does the very same thing.

After trying to bleed the same wheel more then 4 or 5 times or I should say 3, it gets worse and worse. Like let's say this, first bleeding the pedal will go down 2 inches, 2nd it goes 1 inch third only 1/2 or so, and less and less. Less and less fluid coming out too. I can get a decent pedal after a couple pumps with the truck off, but with it running it falls to the floor and I get a brake light on. Ive fought and fought, bleeding after bleeding and still nothing.

I'm going to try one more time then change the MC, and if that doesn't work, I'm changing the prop. valve. If that fails I guess I'll have to get a pressure bleeder.

I removed my RWAL crap did you?

 

[2003Xtreme]

No sir. guessing that is rear wheel anti lock.. and no I did not. I havent had a brake pedal since I got it. Sucks. got great front brakes. I even took the lines off at the master cylinder and pushed the brake to see if I was getting fluid out of the MC and I was. traced it all way back to drums and have fluid back there. my opinion. Has to be MC brake booster or proportioning valve.

 

[Swims350]

well thing is the dump valve goes bad after old fluid is in it and such so it could cause issues and is a big cause of the quishy soft pedals.

The other is I don't see how the booster effects it. It usually just makes the pedal easier to push. When it's bad the pedal is hard.

Mine does the same tho except for loosing fluid and pedal travel after a few bleeds to the same side.

proportioning valves rarely go bad but they can.

I plan to do this to mine...

try it one more time, I've gravity bled them over and over and tried 2 person, but recently took the prop valve apart, the front anyways.

So try that, and if no go I plan to change the MC since it's only $25 for a reman one.

If that fails I plan to buy the prop. valve tool from amazon for $24 and hold the valve open and try it. If that fails I'm buying a prop valve, and if it still fails, new power bleeder for the thing.