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.

HELP! Need tips on using a vacuum pump to self bleed brakes

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by smack, Oct 16, 2002.

  1. smack

    smack 1/2 ton status

    Joined:
    Feb 24, 2000
    Posts:
    277
    Likes Received:
    0
    Location:
    Colorado
    Sorry for the idiocy but I just replaced my master cylinder and front calipers.
    I did a bench bleed on the new MC (from what I could tell I got all the air out using the push/release method) and threw it all together. I went out and bought a fancy smancy vacuum bleeder but I can't get it to work. It's supposed to attach to the bleeder, you pump it 10 to 15 times, then loosen the bleeder and fluid should come down into the little reservoir. Everytime I do it only air comes out and it seems to not be sealing that well on the bleeder (hence the air). I tried all the attachments (even the cone shaped ones that go into the hole of the bleeder) and no significant change.
    What am I doing wrong here!!
    I manually bleed the suckers (with help from my wife)a lot but the pedals still a bit mushy and I gotta get this thing going.
    HELP(^(^*%*&)(*)(*!!
     
  2. imiceman44

    imiceman44 1 ton status

    Joined:
    Aug 5, 2002
    Posts:
    15,160
    Likes Received:
    1
    Location:
    Sacramento, CA
    If you already bled the MC and also bled the calipers but you are still getting some bubbles, do you have a firm pedal now?
    If you do have brakes, and the pedal doesn't go all the way in, then I would just go and usually go up hill and give it a few hard brakes, that usually lets the air go back to the highest place, namely the MC.
    It's worked with me everytime.
    Just make sure you bleed enough to have a firm pedal.
    Also you might want to adjust the rears by baking up and braking repeatedly, that will automatically adjust the rear which sometimes gives you a mushy pedal.
     
  3. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

    Joined:
    Feb 17, 2000
    Posts:
    7,385
    Likes Received:
    0
    Location:
    Atlanta
    If it's fine bubbles it's air getting sucked in around the threads on the bleeder. Don't worry about those. It's still bleeding fine.
    It took me forever to get the master to puke the last air. I would be inclined to think you still have some air in it.
     
  4. smack

    smack 1/2 ton status

    Joined:
    Feb 24, 2000
    Posts:
    277
    Likes Received:
    0
    Location:
    Colorado
    The vacuum pump really isn't pulling any fluid out at all -- can't figure out what I'm doing wrong here.
    I'm gonna do a big, long pedal bleed until I'm sure I've gone through all the fluid and I'm sure that'll do the trick. I just hope it solves my fronts locking problem 'cos I don't want to replace and/or bybass the proportioning valve 'cos I have a frame brace there and I'd have to remove everything.
     
  5. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

    Joined:
    Feb 17, 2000
    Posts:
    7,385
    Likes Received:
    0
    Location:
    Atlanta
    On the propotioning valve is a button under a rubber cap. Try pushing it and see if you can get them to bleed.
    My vacuum kit works great. Never had any problems once I figgured out the little bubbles were coming from the threads.
     
  6. smack

    smack 1/2 ton status

    Joined:
    Feb 24, 2000
    Posts:
    277
    Likes Received:
    0
    Location:
    Colorado
    what kind of adapter do you use on the bleeder??
    I've tried everything in the kit and nothing seems to work!!
     
  7. Mr. Jimmy

    Mr. Jimmy Registered Member

    Joined:
    Mar 14, 2002
    Posts:
    63
    Likes Received:
    0
    Location:
    Haynesville Ga.
    Don't worry about using the fittings, just stretch the clear hose that came with the bleeder over the fittings, you can also put some teflon tape on bleeder screws to prevent air bubbles. Place tubing on bleeder screw with screw closed, pump to about 20-25 in. of vacuum and open screw and continue pumping until no more bubbles
     
  8. smack

    smack 1/2 ton status

    Joined:
    Feb 24, 2000
    Posts:
    277
    Likes Received:
    0
    Location:
    Colorado
    I tried that (with the little hose) and that didn't work either.
    I bought the Mitty Vac Vacuum kit.
     
  9. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

    Joined:
    Feb 17, 2000
    Posts:
    7,385
    Likes Received:
    0
    Location:
    Atlanta
    Take the bleeder out and make sure it isn't full of crud. If the littl cap is missing it doesn't take long for them to get plugged up to the point you can't pull much fluid through them. I usualy use one of the cones and just jam it in the hole.
     

Share This Page