Dash brake light keeps coming on

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73c20jim

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WoW! An idiot light that actually works.
 

bigcountry78

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Did the wheel cylinders today. Rear shoes still look good. Put new cylinders in and the had to go buy a new brake line, the passenger side just twisted apart when I put the wrench on to remove the line. Anyone want to come help me bleed brakes tomorrow? Lol. But seriously, anyone??
 

73c20jim

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Please provide air fare from Tombstone.
 

idahovette

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Fill the master , open the bleeders , pan under each and let gravity work.
 

chengny

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Did the wheel cylinders today. Rear shoes still look good. Put new cylinders in and the had to go buy a new brake line, the passenger side just twisted apart when I put the wrench on to remove the line. Anyone want to come help me bleed brakes tomorrow? Lol. But seriously, anyone??


If you can't convince anybody to help you, here are a couple of ideas;

1. Replace the factory bleed fittings with Speed Bleeders. They have a little ball check valve that prevents ingress of air when the brake pedal is released - but still allows flow out when it is applied.

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2. Or try this:

  1. Get a hose that is long enough to reach the ground and attach one end to the bleeder (make sure it fits snugly on the bleeder nipple).
  2. Put the other end of the hose in a clear glass jar filled 1/4 of the way with fresh brake fluid (the hose should be submerged below the level of fluid).
  3. Now open the brake bleeder. Not all the way - maybe a half turn only.
  4. Get in the truck and begin stroking the brake pedal fully up and down - do it slowly.
  5. As you pump the brakes, any entrained air (and the old fluid) will be purged from that leg of the hydraulic system and flow into the bottle.
  6. After a few strokes, go back and check the contents of the jar. Now it should have some dirty aerated brake fluid in it. Dump that out, and refill the jar with fresh fluid. Go back to the cab and pump the brakes again.
  7. Repeat until the bubbles stop (and the fluid starts running clean).
  8. Close the bleeder, remove the hose, and go to the next brake bleeder.
This works because air is pushed out on the down stroke. But because the hose end is submerged, when the pedal is released, only fluid can be drawn back in.

The down side to this method is that there is a small chance that some of the old fluid can get mixed with the new and get back in. But, the ratio of the mix depends on how often you empty and refill the bottle. (Make sure the bleeder is closed when you do that.)


NOTE: Keep checking the level in the master cylinder - don't let it go dry. If it does, you'll have to start over again.
 
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bigcountry78

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Thanks guys. I knew there had to be a way to do it by yourself.
 

RoryH19

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bigcountry78

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Well I’ve bled the brakes twice now and I still have a brake light coming on. This is getting ridiculous. On to the proportioning valve next I guess.
 

chengny

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Well I’ve bled the brakes twice now and I still have a brake light coming on. This is getting ridiculous. On to the proportioning valve next I guess.


You might consider just pulling the wire off the BPC valve. If the warning light stops illuminating...then the problem is with the BPC valve. If it continues to come on...check for a short to ground somewhere in the associated wiring.
 

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