Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Lost my rear brakes only.

Discussion in 'The Garage' started by rjfguitar, May 13, 2005.

  1. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

    Joined:
    Aug 28, 2002
    Posts:
    9,096
    Likes Received:
    144
    Location:
    california
    I seem to keep losing the back brakes on my K5, but not all the time. I will take off, hit the brakes, have what feels to be all four, accelerate, and then at the next stop I only have front brakes.

    This seems fairly simple since it's pretty much got to be either a master cylinder or proportioning valve going bad. I have never heard of a bad prop valve though. I've got new rear wheel cylinders in my 14BFF and there is no sign of leakage anywhere, reservoir is full. No ABS, it's an 85', you guys no what I have.

    So....master cylinder or prop. valve? Or something I am overlooking?

    As always, thanks. :)
     
  2. HELLBENT DESIGNS

    HELLBENT DESIGNS 1/2 ton status

    Joined:
    Apr 2, 2005
    Posts:
    453
    Likes Received:
    0
    Location:
    bozeman mt
    how old are the rear brake hoses? they can look perfect on the outside and be collapsed on the inside. when you bleed them do you get normal fluid flow?
     
  3. hi pinion

    hi pinion 3/4 ton status

    Joined:
    Sep 25, 2003
    Posts:
    5,354
    Likes Received:
    0
    Location:
    **PLUMBING THE WORLD**
    :) Check your brake fluid
     
  4. FWP

    FWP CRS

    Joined:
    Oct 11, 2000
    Posts:
    3,845
    Likes Received:
    3
    Location:
    Prescott Valley, AZ
    I'd put a new master cylinder in.
     
  5. Ryan B.

    Ryan B. 3/4 ton status GMOTM Winner

    Joined:
    Jul 18, 2001
    Posts:
    5,693
    Likes Received:
    0
    Location:
    CA
    Did you try bleeding the rear brakes again.. both sides.. just to be sure?
    I guess i'd put a master cylinder in next.. but BE SURE to BENCH BLEED it before you put it in... I had a buddy that figured he'd hook up the master cylinder and just bleed it with it in the car... doesn't work.
     
  6. danieldick

    danieldick Newbie

    Joined:
    May 13, 2005
    Posts:
    1
    Likes Received:
    0
    Location:
    Indiana, PA
    New master cylinder

    I have a 72' Blazer that the idiot light came on for the brakes. I could take the pedal to the floor and then come up and all the brakes would then apply. I put a tru-torque master cylinder in and it fixed the problem.

    If it can be seen, it can be hit. If it can be hit, it can be killed.
    Armor theory
     
  7. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

    Joined:
    Aug 28, 2002
    Posts:
    9,096
    Likes Received:
    144
    Location:
    california
    Normal fluid flow to the rear brakes, both times I checked. My galvanized lines are almost new, I put new lines on my 14BFF when I installed it. The line that comes down from the body is original though.

    I am also thinking master cylinder. I guess the chances of a prop valve malfunctioning is not common?

    Ryan,
    how do I bench bleed the cylinder?

    Jake,
    Read the dang post, yes I checked the fluid level. :p:
     
  8. tucsonkfive

    tucsonkfive 1/2 ton status

    Joined:
    Jun 9, 2002
    Posts:
    133
    Likes Received:
    0
    Location:
    Tucson, AZ
    I've known a couple of guys who had to replace the preportioning valve. They ain't cheap but might be worth splurging when it comes to brakes.
     
  9. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

    Joined:
    Aug 28, 2002
    Posts:
    9,096
    Likes Received:
    144
    Location:
    california
    What are symptoms of a bad prop valve?
     

Share This Page