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Brake booster swap questions

Discussion in '60-Series Wagons' started by beatdown83fj60, Mar 3, 2007.

  1. beatdown83fj60

    beatdown83fj60

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    Ok you guys are probably sick of my brake questions, heck I'm getting sick of them. I have searched high and low for a brake leak on this beast and cannot find it so I'm sure that it's leaking from the master into the booster. I have a used master/booster combo of a 92 toy pickup 4cyl 4x4. Is there a way to determine if the combo or one of the components is bad doing home bench testing? If I bench bleed the master and it's a leaker, will I be able to tell at that point, or will I have to put it on to find out? Also my cruiser booster is bad, if I tested it correctly according to what I've read here. Give it a few pumps, and it flat out goes to the floor, and doesn't drop any further when I start the vehicle. Also when I'm driving down the road, I can get a little pedal when I pump it then when I hold it sits still for a minute, then with delayed reaction (I'm talking ten seconds or so) It drops another 1-2 inches and I get brakes. Right now I have no brakes whatsoever, unless I time it just right, pump it up 3 times, then hold the pedal and wait for it to fall and the booster to kick in. It's my only vehicle and it's too cold in Colorado to ride a bike right now. Can I bench test the booster from the mini on a bench? When I push the rod on the mini booster in it hisses, when I plug the vac line I can't get the rod to barely budge (I didn't press too hard though through fear of hurting something by forcing it). Should I just slap the crap on, bleed it, and see if it all checks out? I also have the calipers with brand new brake pads from the same vehicle to match which I cleaned up and inspected tonight. They will be going on at the same time.
     
  2. dd113

    dd113

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    SOunds like you new booster is fine. For leaks on a 62, spceially a rust belt 62 look at the LSPV and the lines along the frame. Make sure you bleed the LSPV as well.

    Used brake parts are a bad idea. Aftm brake MC is not expensive but OEM is much better and not that much more.

    A good booster test is to remove and plug the booster the vac line to the booster and see if you ahve any diffeerence in brake
     
  3. Mace

    Mace rock scientist.. Staff Member s-Moderator

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    turn the motor on, pump the brakes, if the motor stumbles, you have a leaky booster.
     
  4. beatdown83fj60

    beatdown83fj60

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    Ok, well I'm going against my hopes of this master working out, and just buying a new one today. I'm gonna put it on the old booster and see if it works, the motor doesn't stumble when I start the truck with the brake on so maybe I'm good there. The calipers are mine so I know they are in good shape. I'm also putting new flexible brake lines on it for piece of mind. If I still have problems, I'll chase the lines down along the frame rail. The LSPV? Is it the same as that funky contraption i've had bolted to the frame rail on all my pick ups with the arm that reaches down to the axle? If so I may just bypass it, I did on my last rockcrawler and didn't notice a difference because it was all siezed up anyway.
     
  5. Mace

    Mace rock scientist.. Staff Member s-Moderator

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    nope..


    start the truck, get it idling, then pump the brakes
     
  6. beatdown83fj60

    beatdown83fj60

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    Tried that, still doesn't stumble, so my booster must be ok. For those of you that had line leaks, did it leak on the rear line on the frame rail above the skidplate? I have a bunch of crap there, but I can't tell if it came from my old leaky output seal, or it may be brake fluid.