Rotted rear brake line along frame rail now soft pedal after bleed?

[ecaldwell78]

It was a normal day picking up the babies after work when "pop", I lost a brake line along the frame rail. After replacing the line and bleeding the system, my pedal is super soft and takes a considerable amount of pedal travel and even then a delayed start in the brakes actually grabbing. I don't know if it matters or not but the pedal hisses when depressed. I don't know if it did this before the repair or not, I just notice it now because of the problems. When I bled, all I did was the "four corners" in the proper sequence until I saw no bubbles. Did I miss something obvious? Is there more I need to do since I ran the MC dry before I could get the rotten line changed? Brakes on all four corners are new and the rears are adjusted properly. ABS light has been on since I've owned the truck but the brakes were fine before the ruptured line. I know this has been discussed before as I found searching the forum, but any help is greatly appreciated since I use this rig on the daily to pick up my boys from daycare. Thanks guys!
Evan

 

[Swims350]

brakes need bled. if not then you may need to look into bench bleeding the MC, replacing it. There also may be something to do with the proportioning valve or abs system since it had a line blow but now sure, kind of like a reset type thing or something.

 

[///RAGMC]

Sounds like you still have air in the system. These trucks are a pain to bleed afrer you replace anything. I found the best way to bleed the brakes on these truck is with something like this http://cgi.ebay.com/ebaymotors/Pneu...t=Motors_Automotive_Tools&hash=item5644d7d294

 

[ecaldwell78]

Thanks for the quick replies fellas! Yeah I cheaped out and bled the old fashioned way because by the time I was done fighting that old line and bending the new one I was wiped out. So it looks like I'm breaking out the Mity-Vac this weekend! I really thought it was bled well enough just by seeing the fluid at the back bleeders, but I should have known better than to half ass it. Thanks again and if by chance that doesn't do the trick, then I'll be back with more stupid questions!

 

[ecaldwell78]

*UPDATE*
I hope everyone had a good, safe 4th! Well I've got a good pedal feel now. I had a lot of air in the front driver. She stops "almost" as well as when I got her. The only time there seems to be hesitation between pushing the pedal and the brakes engaging now is when I try to do a panic stop and really jam on the pedal. I couldn't lock those brakes up no matter how hard I tried. Any ideas on that one since under normal driving conditions all is well?

 

[Swims350]

it's called antilock brakes they aint supposed to lock up.

 

[RHamill]

it's called antilock brakes they aint supposed to lock up.

x2...

Why would you 'try' to lock up your brakes? That's hard on everything in the master cylinder, you don't want to destroy that square cut seal, or have your primary piston SLAM in to the secondary that fast.

OR blow a wheel cylinder, wear your pads and shoes down faster, blow another brake line..

 

[ecaldwell78]

I apologize for not making my thoughts clear guys. The ABS hasn't worked since I've owned the truck and I've locked them up on occasion out of necessity. Tires cost to much to do it for "fun". I guess the point I was trying to make is that I was "testing" the brake job to make sure I could bring her to a stop in short order if I had to and when I jam on the pedal, say if someone short stopped in front of me or didn't use a signal to turn, it still takes a second or so before the brakes engage. Under normal braking they perform like a champ. I'm just trying to get all the bases covered because I don't want to put the kids in danger from something I could have done to make her stop better under extreme circumstances.

 

[RHamill]

I apologize for not making my thoughts clear guys. The ABS hasn't worked since I've owned the truck and I've locked them up on occasion out of necessity. Tires cost to much to do it for "fun". I guess the point I was trying to make is that I was "testing" the brake job to make sure I could bring her to a stop in short order if I had to and when I jam on the pedal, say if someone short stopped in front of me or didn't use a signal to turn, it still takes a second or so before the brakes engage. Under normal braking they perform like a champ. I'm just trying to get all the bases covered because I don't want to put the kids in danger from something I could have done to make her stop better under extreme circumstances.

Oh ok, after I posted that I figured you probably had the ABS fuse out or bad speed sensors in your bearings causing you to have no ABS at all.

 

[ecaldwell78]

No worries RH. I don't know if this plays into the equation at all, but I noticed yesterday that my good pedal feel (minus the delay if I panic stop) doesn't feel so good if I have the air conditioner on. I've NEVER encountered this before. I'm really stumped and if it wasn't for the time invested and my foolish pride, I would be taking this to a pro for sure! Any further insight would be great and as always very much appreciated.