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.

Bled brakes now what?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by sinchphoto, Jan 9, 2002.

  1. sinchphoto

    sinchphoto 1/2 ton status

    Joined:
    Mar 7, 2000
    Posts:
    366
    Likes Received:
    0
    Location:
    Southern California
    Bled all brakes and did have some air but pedal still goes way down. Is there a halfway point somewhere where all the brakelines meet? if so can it be bled?

    Check this out. I raised the rear and put on jackstands. I let the truck run and hit the breaks. The rear left tire slows down but does not stop while the rear right stops completely.
    Brake shoes too loose? or bad cylinder?
     
  2. Slayer

    Slayer 1/2 ton status

    Joined:
    Oct 17, 2001
    Posts:
    225
    Likes Received:
    0
    Location:
    Eastern Colorado, jokingly referred to as Western
    I'd bet on the bad master cylinder (internal imbalance).


    <font color=blue>I don't know everything, I just think I do.............</font color=blue>[​IMG]
     
  3. Ovrtym

    Ovrtym Registered Member

    Joined:
    Dec 15, 2001
    Posts:
    21
    Likes Received:
    0
    Location:
    Virginia
    Did you bleed the brakes in sequence? Start at the brake farthest from the master cylinder working your way to the closest - right rear, left rear, right front, left front.
     
  4. Wheels

    Wheels 1/2 ton status

    Joined:
    Aug 18, 2000
    Posts:
    638
    Likes Received:
    0
    Location:
    Native Floridian living in Oklahoma, USA
    Check the proportioning valve on the crossmember at the front. On the drivers side there is a switch that when there is a difference in pressure between the rear and front it will trip and apply most of the pressure to the front but will give the impression that the brakes are bleeding down. Push in on this switch (it's hydraulically actuated) and rebleed the brakes in sequence (left rear, right rear, right front and left front). Check the switch between bleeds and reset as necessary.
     
  5. kilroy

    kilroy Registered Member

    Joined:
    Nov 25, 2001
    Posts:
    85
    Likes Received:
    0
    Location:
    Alaska, Anchorage area
    To check your rear drum adjustment. Raise vehicle, engage parking brake 4 clicks, adjust each side until it drags slightly, with the same amount of drag on each side, release parking brake, there should be no drag. This will get you very close.
     
  6. BurbinOR

    BurbinOR 3/4 ton status

    Joined:
    Feb 17, 2000
    Posts:
    5,829
    Likes Received:
    0
    Location:
    Oregon
    I'd first recheck the rear drum adjustment.............then have the brakes power bled at a 4X4 shop or dealership. That was the final and only thing that worked for me when we did my one ton conversion.................the upside is I got one heck of a brake line flush while trying to bleed them myself [​IMG]

    <font color=blue>'79 ONE TON TPI K5 - See it at---&gt;<a target="_blank" href=http://www.blazzinor.rockcrawler.com/>BlazzinOR's Beast Buildup</a>
     
  7. sinchphoto

    sinchphoto 1/2 ton status

    Joined:
    Mar 7, 2000
    Posts:
    366
    Likes Received:
    0
    Location:
    Southern California
    This proportioning valve thing sounds interesting I'll check it out. I think slayer might be right about the cylinder. yes i have bled in sequence. &amp; i do believe the rear brakes might need to be adjusted.

    thanks for the help!!
     
  8. sinchphoto

    sinchphoto 1/2 ton status

    Joined:
    Mar 7, 2000
    Posts:
    366
    Likes Received:
    0
    Location:
    Southern California
    i might get rear disk brakes, so that will probably solve a part of my problem but if its the P valve thats the problem then I will continue to still have trouble right?
     
  9. dyeager535

    dyeager535 1 ton status Premium Member

    Joined:
    Dec 13, 2000
    Posts:
    26,977
    Likes Received:
    189
    Location:
    Roy WA
    The proportioning valve almost NEVER fails, so consider it one of the last things to consider. That "relief valve" is also one of those things that almost no one ever has to touch. I'm not saying that valve can't be a problem, just on the list of likelihood, its not at the top.

    Typically, when you bleed brakes, you end up with the pedal going to the floor. When the pedal hits the floor, the master cylinder piston travels further than it has since it was last replaced. That means into all the assorted crud that has built up, as well as any corrosion that has built up. You end up scuffing or ripping the rubber seals on the piston, and fluid leaks by, thus, you never get a firm pedal.

    I bled my system for two days (on and off of course : ) and finally said screw it. About two weeks later, sitting at a light, the pedal went to the floor, and the brake light came on. Immediately replaced master cylinder, brakes bled with ease, and the problem has never recurred.

    Dorian
    My tech/links page: <a target="_blank" href=http://www.dorianyeager.com/index2.html>www.dorianyeager.com/index2.html</a>
    Why insist on counting when the ring gear has the tooth counts stamped in?
     

Share This Page