No fluid coming from rear brakes when I try to bleed!

[ShannanC]

My friend came home the other day and told me that her brakes were bad on the 99. I have a 98 Limited and she has a 99 Limited. I took it for a drive and the brakes were slowly bleeding down and the stopping power was greatly reduced from the day before. I checked the MS reservoir and found that it was almost empty. I added fluid and tried to bleed the brakes with a helper and the front were great but only one squirt from the rear driver and nothing at all from the rear passenger. I figured that the master cylinder might have crapped out so I bought another one. I bled the air from the MS prior to installing, removed the old MS, and installed the new. I went to start bleeding the system with a Mitivac and STILL nothing from the rear wheels! Please HELP!!

 

[I_bRAD]

How are the lines?

 

[ShannanC]

They seem to be fine. No leaks. I just traced them down for kinks and didn't find any.

 

[Unner]

On my 01 you have to have the key in the ON position and to bleed the rears you just hold the pedal down and open the bleeder, the fluid is pumped out until you close it. Something to do with the ABS system I believe. I'm not sure if you 99 is the same way or not, but it's just a thought.

 

[ShannanC]

Thanks. I'm not sure if the 99 is the same either. I will try that tomorrow.

 

[OkiSurf1996]

I was having his same problem with mine. The wheel cylinders were leaking into the boots. Whenever I would bleed, it would just pull air through the wheel cyclinder and out the bleeder screw. I was using a pneumatic bleeder though. Worth taking a look at, replaced wheel cyclinder and it works fine now.

 

[cashmoney]

Fyi my 2000 I did not need the key on to bleed the rears. Just some more information for you.

 

[3bears]

for what its worth

a friend of mine had a very similar problem yet older chevy

but same issue, no fluid getting to rear wheels, all else seemed fine, finally I susgested we track down the block or restriction ( we had already checked at the master cylilnder and abs by cracking lines loose there) so starting at the back we bust the rear single break line loose and see if we are getting fluid there. .....no not at rear axle...so went to other end of the rubber flex hose, busted it loose.....fluid there.

ive only seen this , this one time in all my years....
but moral of the story
a rubber brake hose can fail and look totally good from the outside somehow this was blocked on the inside, yet no swelling

now when ever I do a major break job on high mile cars, I always include new lines. and quality stainless at that

 

[ShannanC]

Thank you to all of you for the information. I will post what the issue was once it is tracked down. If anyone has any other information or ideas I am more than welcome to any input. Thanks again.

 

[I_bRAD]

for what its worth

a friend of mine had a very similar problem yet older chevy

but same issue, no fluid getting to rear wheels, all else seemed fine, finally I susgested we track down the block or restriction ( we had already checked at the master cylilnder amd bas by cracking lines loose there) so starting at the back we bust the rear single break line loose and see if we are getting fluid there. .....no not at rear axle...so went to other end of the rubber flex hose, busted it loose.....fluid there.

ive only seen this , this one time in all my years....
but moral of the story
a rubber break hose can fail and look totally good from the outside somehow this was blocked on the inside, yet no swelling

now when ever I do a major break job on high mile cars, I always include new lines. and quality stainless at that

I had the same thing happen on my Volvo- I thought the caliper was seized and didn't discover it until I took the caliper off and realized it was fine. That was just fine with me as a flex hose is much cheaper than a caliper!

 

[ShannanC]

Still no luck!!

Here is my update so far: My right rear wheel cylinder had failed. I replaced both wheel cylinders on the rear and both sets of brake shoes. I checked the ONE soft line that I have that is above the differential that tees off to both rear lines and it appears fine. Fluid will flow through the driver's rear line when it is pumped up with a Mitivac just fine BUT very little fluid if any comes out of the passenger's rear line when I pump it up to bleed it with the Mitivac just air. I know fluid moves through the hard line because it was flowing out when I had it disconnected to replace the wheel cylinder and after the wheel cylinder replacement when I had disconnected the line to check it because I am second-guessing myself. Ummmmm.....WTF?! Any ideas?

P.S. I apologize for grammatical and spelling errors as I am typing as fast as I can think.

 

[ShannanC]

Another update - just in case anyone is interested

Latest update: I removed the bleeder valves on the rear and put a couple of wraps of teflon tape on the threads. This helped with the Mitivac holding a constant vacuum but it still wasn't pulling any fluid through the lines. I had my friend come out and help bleed the brakes the traditional way and all lines flowed fluid and the air was bled out rather quickly. The car had nice pedal and all was fine until I took it for a test drive and now when you push the brake pedal it will slowly sink to the floor just like it did the other day. So again I say WTF?

Air in the lines still?
Brake booster also?
How in the hell can the entire brake system take a complete dump at once?

 

[3bears]

air in the master cylinder ? did you bleed it ?
Did you do all the brakes in the correct order?

Ive had cars I have had to do several times

I have had cars and motorcycles that the only way that worked was a pressure bleeder at the master cylinder

 

[nevada]

Latest update: I removed the bleeder valves on the rear and put a couple of wraps of teflon tape on the threads. This helped with the Mitivac holding a constant vacuum but it still wasn't pulling any fluid through the lines. I had my friend come out and help bleed the brakes the traditional way and all lines flowed fluid and the air was bled out rather quickly. The car had nice pedal and all was fine until I took it for a test drive and now when you push the brake pedal it will slowly sink to the floor just like it did the other day. So again I say WTF?

Air in the lines still?
Brake booster also?
How in the hell can the entire brake system take a complete dump at once?

assuming you don't have a fluid leak somewhere, I would say bad MC.
yes, I know you just replaced it. I have seen them be bad right off the same. its not all that uncommon actually.

 

[HiLife]

If you ran the master cylinder dry and didn't bleed the master cyl only first, before bleeding the lines, there's a good chance you got air into the abs. You need to cycle the abs unit by scan tool or braking on dirt. Get back to garage and bleed again.
On the passenger side lines I would work backwards making sure I got full fluid flow at each connection starting at the wheel cylinder. Rubber brake lines might look fine on the outside, but, they do collapse on the inside. I had one of those.

 

[Dephcon]

Already mentioned here, a single rubber line from the body to the rear axle tee. If the driver side is getting fluid then its most likely not the rubber line. Fluid will always go the path of least resistance. If you have the driver side rear all buttoned back up, drum on and crack the passenger rear bleeder, fluid should flow out of it.

When i did my breaks and was having trouble getting all the air out, the issue with mine was I didn't have the bleeders open enough. Yes, sounds weird, but an extra quarter turn and the fluid squirted out easier as well as the air. I used a self bleeder system (cup with inlet with a hose that goes to the bottom of the cup, lets air out, but sucks back in fluid). Took me a few times to get all the air out, but I finally did.

 

[nevada]

Already mentioned here, a single rubber line from the body to the rear axle tee. If the driver side is getting fluid then its most likely now the rubber line. Fluid will always go the path of least resistance. If you have the driver side rear all buttoned back up, drum on and crack the passenger rear bleeder, fluid should flow out of it.

When i did my breaks and was having trouble getting all the air out, the issue with mine was I didn't have the bleeders open enough. Yes, sounds weird, but an extra quarter turn and the fluid squirted out easier as well as the air. I used a self bleeder system (cup with inlet with a hose that goes to the bottom of the cup, lets air out, but sucks back in fluid). Took me a few times to get all the air out, but I finally did.

if a single rubber hose is feeding the T that goes to both rear brakes, then both rear brakes would have an issue, if the rubber hose was bad.

he sad earlier that traditional bleeding methods got it to bleed correctly. so the hose isn't bad.

 

[Dephcon]

if a single rubber hose is feeding the T that goes to both rear brakes, then both rear brakes would have an issue, if the rubber hose was bad.

he sad earlier that traditional bleeding methods got it to bleed correctly. so the hose isn't bad.

I screwed that up, should have been a T not a W. Proof reading is key to not looking like an idiot!

 

[rideexileex]

Air in the ABS is a major PITA... It's the main reason I'm ordering new brake fittings. ABS is going bye-bye

 

[ShannanC]

Latest update: I removed and returned the new master cylinder to Autozone and they exchanged without any problems. I bled the newest new one and installed it. The brakes are a lot better! I drove it to an unused parking lot and adjusted them the rest of the way by backing up & pulling forward. Yall know the drill. I then took it for a drive and slammed on the brakes to get the ABS to activate a few times. I went home but couldn't get any help to bleed the brakes one last time but all seems like it is okay. Once I bleed them a final time I will let yall know how it all comes out. I'm extremely grateful for all of the opinions and advise. This forum is the standard that I hold all other forums to. Thanks again.