Still got a soft pedal please help

[klowninc89]

hi i have a 1990 k5 blazer with 5.7L and i just did all brake work as in all new ....except rotors and drums. my prob is it has a soft brake pedal and seems to catch about half way down....been bleed many time by me and a shop. my question is what can i do to beef up this brake system and fix this problem??/ can it be booster??? i here a puff of air when i use the brake inside the cab. can i use a suburban brake system to help? please any and all input would be sweet. thanks...Matt

 

[lizard49]

sounds like break booster. I replaced the master cylinder 1st, the booster turned out to be the prob. by process of elimination...i.e. I had replaced everything else.
you don't have to crack the lines to replace it either. mine is a 1988 K5

 

[Greg72]

Agreed.

On my Suburban I replaced a defective master cylinder and it had already wept fluid into the booster. I didn't notice it originally and couldn't get a decent pedal with the new MC installed. Repeated the bleeding procedure MANY times with no luck.

Finally CK5 came to the rescue and suggested it was a bad booster. I swapped in a new one and WHAM! the brakes were perfect.

 

[klowninc89]

Thanks guys i will try the booster thanks a lot!!