bleeding 94 Suburban-air from rear wheel cylinder

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  #1  
Old 07-13-05, 06:37 AM
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bleeding 94 Suburban-air from rear wheel cylinder

Everything is new(pads, rotors,shoes, drums and wheel cylinders). Every time right rear wheel(passenger side) is bled air comes out then nice clear flow of fluid. Then I try to bleed the wheel again and again get a spurt of air then clear fluid flow. Cannot get rid or the air spurt. The brake pedal is low at least for a whole brake job but yesterday the pedal came up a bit and braking was fairly ok. Checked all parts for loose connections and everything looks ok.
Don't know what to try next, all other wheels bleed ok except for right rear.
TIA, Frank C.
 
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  #2  
Old 07-13-05, 02:23 PM
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Could be a defective W/C. Try gravity bleeding: remove the Mas Cyl cap and make sure the fluid is topped off; with the Mas Cyl cap off, open the bleeder at that wheel and just let it drip through 1/2 - 3/4 of the fluid in the Mas Cyl. Close the bleeder, top off the fluid and replace the cap. Pump the pedal 3-4 times. Open the bleeder to "burp" it. If any air comes out, just leave the bleeder open and repeat the steps. This can all be done without a helper. If, after the second try you still get air, you can narrow it down to the rears by pinching off the flex hose at the rear axle.
 
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Old 07-15-05, 07:08 PM
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1. Make sure you have adjusted the brakes properly. This could be your low pedal.

2. Open the bleeder very slowly. Sometimes if you open it too fast with a lot of pressure on the pedal you will get what looks like air but is actually just fluid spray.

If you still have a low pedal and find air only at that wheel, I would replace the wheel cylinder.
 
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Old 07-15-05, 07:35 PM
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pmheritage is right again, gravity bleed first!Nothing better than a agressive pumper on the pedal foaming the fluid.
 
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Old 07-18-05, 10:51 AM
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Air from rear wheel cylinder-bleeding 94 Suburban

OK I bled the rear cylinder as you said, just to confirm, after pumping the brakes a few times, then going to the wheel cylinder in order to "burp" it, I take it that I do not remove the cover from the mast.cyl.
TIA, Frank C.
 
  #6  
Old 07-18-05, 10:58 AM
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Correct - cover needs to be installed on the Mas Cyl when applying brakes. Unless you want a considerable mess on your hands!
 
  #7  
Old 07-18-05, 11:26 AM
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air from rear wheel cylinder-94 Suburban

After I pump the brakes, do I leave the m.c. cover intact when I bleed, open up the wheel cylinder, or do I take the cover off the mast. cyl., after I pump the brakes, but before I open the wheel cylinder?
I'm just asking this because I had the cover off in gravity bleeding the wheel cylinder.
TIA, Frank C.
 
  #8  
Old 07-18-05, 12:16 PM
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I'd leave it on until after you open the bleeder, just to see what happens. If you get the air, just leave the bleeder open and remove the cap again.
 
  #9  
Old 07-18-05, 04:00 PM
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Bleeding 94 Suburban-air from rear wheel cy..

It worked perfectly. When I pumped the brake pedal then opened the wheel cylinder nothing but fluid came out. I then had to go shopping for some stuff so I gave it a nice test drive. The pedal goes down about 2-4 inches then you hit good solid braking pressure. I would think the pedal free play is normal.
I have an awful confession to make. This morning when I picked up the hood to start the procedure and took the cap off the mast. cyl. the smaller cup of the mast.cyl. looked like it was bone dry-there was no fluid.
I then gave a close inspection to the back of each wheel and the left, passenger side, rear wheel looked a little wet. I took the wheel off to get a close look and yep, it looked like the brake fluid line was a little loose with a little seepage coming out of it. I tightened it up over two turns yet still got a mushy pedal so went on with the gravity bleeding procedure for the other rear wheel and everything went fine.
The gravity bleeding went so well just for drill I think I'll bleed the left wheel. the one with the previous loose brake line screw to insure there is no air trapped in after I tightened the brake line screw.
Thanks for all your help. I appreciate all comments made.
Frank C.
 
  #10  
Old 07-18-05, 04:15 PM
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Definitely bleed the one that was leaking. Just repeat the gravity bleed procedure. The pedal will likely tighten up a bit for doing it. Double check your adjustment too.
 
  #11  
Old 07-23-05, 07:56 AM
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Adjusting brakes on 94 Suburban

How do you know when the brakes are adjusted properly? Should the shoes be expanded to where there is a slight drag putting on or taking off the drum? Should there be a very pronounced drag with the drum taken off with a little more than slight iffort?
Then there is the way of lifting the whole rear axle, spinning the tires and feeling a slight drag-maybe this way is the more proper way.
TIA, Frank C.

Originally Posted by hspr
1. Make sure you have adjusted the brakes properly. This could be your low pedal.

2. Open the bleeder very slowly. Sometimes if you open it too fast with a lot of pressure on the pedal you will get what looks like air but is actually just fluid spray.

If you still have a low pedal and find air only at that wheel, I would replace the wheel cylinder.
 
  #12  
Old 07-23-05, 08:14 AM
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Originally Posted by jocaan
How do you know when the brakes are adjusted properly?
TIA, Frank C.
Axle raised, trans. in nuetral - slight drag when spinning drums.
 
  #13  
Old 07-26-05, 10:36 AM
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bleeding 94 Suburban-air from rear wheel cylinder

Thanks.
Frank C.
 
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