brake issues

[cmvtx]

Question for the tech. Over the weekend I replaced all four rotors, calipers and pads on my 99 silverado Z71(nbs). I bled the brakes the traditional two person way starting at the farthest wheel and ending with the front left. I went through about a quart of fluid doing it and was certain all the air was out. The pedal travels further than before this work was done. I bled again last night and got a little air out of the right rear, with not much improvement in the pedal travel. No other lines were opened other than at the calipers and there is no fluid loss anywhere. I have done brake jobs on several of my vehicles however this is the first time on one with abs. Is there a better way for me to bleed these lines successfully or do I have to keep doing it over and over until the pedal comes back to normal??? BTW it does stop fine however the pedal is about 3/4 of the way to the floor before it will. Thanks for the help

[bobcat5544]

WHEN YOU BLED THE SYSTEM DID YOU LET THE MASTER CYLINDER FLUID GET LOW.

 

IF NOT THEN KEEP BLEADING THE SYSTEM

[cmvtx]

Nope, fluid level never went below 1/4" from max mark. I do notice with the vehicle off the brake it high and hard by the second pump. But if you hold the brake and start the engine it will drop.

 

Does this model just require repeated bleeding to finally get it right?

[bobcat5544]

it is normal operation for the brakes to get hard with engine off, and then drop like that when you start the engine.

 

some time it is nessasary to bleed the system a few times.

doing a vacuum bleed is better than pumping the brakes method

[cmvtx]

Ok Thanks I'll try the vac bleeding method when I get back into to town this weekend and report back on the result.

[alvocado]

I've heard of this happening when air gets into the fluid in the ABS system. If that's the case, you need to activate the ABS to bleed the fluid out and this can be done via computer at the dealer.