Mushy Brake Pedal After New Brake Lines

[Scottydoggs]

if you guys got hydro boost you can also bleed the booster and its lines. can fix a mushy pedal.

i just jack the front up via the front frame till both front wheels are off the ground.

engine running pumps the brakes 20 times, then turn the engine off, but leave the key to run and turn the wheels lock to lock like 12-15 times.

about every time i do this p/s fluid burps out the pump cap, on or off, so lay some cardboard down in case it burps and spills over on ya. nothing like that surprise on a nice clean driveway. yeah i got burned once lol

 

[Lord Snax]

if you guys got hydro boost you can also bleed the booster and its lines. can fix a mushy pedal.

i just jack the front up via the front frame till both front wheels are off the ground.

engine running pumps the brakes 20 times, then turn the engine off, but leave the key to run and turn the wheels lock to lock like 12-15 times.

about every time i do this p/s fluid burps out the pump cap, on or off, so lay some cardboard down in case it burps and spills over on ya. nothing like that surprise on a nice clean driveway. yeah i got burned once lol

Thanks for the info! I will try this when I get finished installing my new mc. Turns out the old one was built on Feb 22, 2005. Defiantly time for a replacement!

 

[sunrisor]

Last fall I had a rusted brake line blow in my '03 XL (fortunately, no harm to people or vehicles). I then replaced EVERYTHING. Decided to do some other work while I was under there, so it sat for a couple months.
Tried a pressure bleeder (hand pump style), thought it was working ok, but still mushy pedal. did it the old fashioned way, still mush. Thought the new M/C was bad, replaced again, still mush.
Once I finished the other work, I had enough pedal to bring to a shop to have ABS bleed done. Shop claimed they did it. Pedal was ok enough to drive, but pedal still was a bit mushy.
After a couple months of intermittent driving, got in to go to work, tested the brake (like I always do, because I don't trust it), on the 2nd pump it went straight to the floor.
No leaks that I could see. Fluid level down a little. Did the brake bleed the old way again. Pedal is hard w/engine off. Running, it still has a long pedal travel, but does come up and stops somewhat normally.
I agree with someone above--GM SUVs of this era do have long pedal travel/soft brake pedal. But I think the pedal has too many pumps (while running) til the pedal comes up. Pedal w/engine off is rock hard.
I took it for a test drive and beat the crap out of the brake system. It stops ok, although couldn't get ABS to activate.
I think I'm going to try to bleed it again....Any suggestions as to where air can get in, but fluid can't come out?

 

[brasil]

Last fall I had a rusted brake line blow in my '03 XL (fortunately, no harm to people or vehicles). I then replaced EVERYTHING. Decided to do some other work while I was under there, so it sat for a couple months.
Tried a pressure bleeder (hand pump style), thought it was working ok, but still mushy pedal. did it the old fashioned way, still mush. Thought the new M/C was bad, replaced again, still mush.
Once I finished the other work, I had enough pedal to bring to a shop to have ABS bleed done. Shop claimed they did it. Pedal was ok enough to drive, but pedal still was a bit mushy.
After a couple months of intermittent driving, got in to go to work, tested the brake (like I always do, because I don't trust it), on the 2nd pump it went straight to the floor.
No leaks that I could see. Fluid level down a little. Did the brake bleed the old way again. Pedal is hard w/engine off. Running, it still has a long pedal travel, but does come up and stops somewhat normally.
I agree with someone above--GM SUVs of this era do have long pedal travel/soft brake pedal. But I think the pedal has too many pumps (while running) til the pedal comes up. Pedal w/engine off is rock hard.
I took it for a test drive and beat the crap out of the brake system. It stops ok, although couldn't get ABS to activate.
I think I'm going to try to bleed it again....Any suggestions as to where air can get in, but fluid can't come out?

Are you 100% sure, that the "shop " did a good job ? sounds like you still have air in your system. I bought a handhold tester, who can do the ABS Block bleeding. I don´t trust any shop at all... was foolished more than once.

 

[sunrisor]

brasil...I agree, it sure feels like there is still air in there. I did a manual bleed last time and got a bunch more air out. The pedal came up and hard. But...it still feels mushy when you first start it up.
I think it's time to invest in a handheld....
I need a new one anyway since the one have doesn't work on my '15 Silverado.

I just saw this one:
https://www.amazon.com/FOXWELL-NT63...bs+tester&qid=1558376770&s=automotive&sr=1-11

 

[brasil]

this foxwell handheld looks good... also the price is good. i would give em a try