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hydroboost

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by MUDNUTT, Oct 18, 2001.

  1. MUDNUTT

    MUDNUTT 1/2 ton status

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    if anyone is considering doing this mod. all i can say is DO IT. i just finished my install and the difference is incredible. if you do this you will not be sorry. now i just have to round up the pieces for my rear disc brake conversion and i'll be able to stop faster than a yugo can accelerate to 50 mph. lol!!
    deck

    <font color=blue>DRIVE IT LIKE YOU STOLE IT[​IMG]
    <font color=red>PROUD TO BE AMERICAN[​IMG]
     
  2. backlash

    backlash 1/2 ton status

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    Mudnutt,

    Tell me about the mod? What did you do ... I have an 88 that has a 'soft feel' upon braking. HArd to really brake well ...
     
  3. nofeartruckin00

    nofeartruckin00 1/2 ton status

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    I was picking up a P/S pump the other day, and they asked if i had hydroboost, what is it??

    Mud, the ultimate paint job
     
  4. BorregoK5

    BorregoK5 1/2 ton status

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    Hydraboost uses your power steering pump hydraulics to assist your braking hydraulics. Its very smooth and easy to actuate. Best of all, its not effected by vacuum so you maintain a consistent pedal feel under loaded conditions.

    "I'm looking for a Dana60 Front Axle.." I asked, "You wish! HAHA" the wrecker replied! - <a target="_blank" href=http://www.echobit.com:81/k5/> Pictures</a>
     
  5. backlash

    backlash 1/2 ton status

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    Just curious. How hard is this mod. to do? Is it possible that I already have it? Stock?

    When I slam on my brakes I hear a jush of air, the pedal falls a few inches before the brakes (appear) to apply. Very dangerous if I were to get cut off or ... God forbid ... a kid walks out in front of me.
     
  6. Danno

    Danno 1/2 ton status

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    I've got hydroboost on my K5, and it's great.

    It looks like you'd need a different master cylinder, lines, and the PS pump with the setup for the brakes. It doesn't look like it would be a difficult conversion. I've never done it, though, just saying it doesn't look complicated on my truck.

    Thank god I've got hydroboost too... I've been having all kinds of wierd vaccuum related problems lately. It's nice not having to worry about the brakes!


    1984 K5 Blazer 4x4 Silverado
    6.2L diesel, 700R4, 3.42 gears, 31x10.5" tires
     
  7. Burbinator

    Burbinator 1/2 ton status

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    You don't currently have HydroBoost if you hear a "whoosh" sound as you apply the brakes and inches of pedal travel. What you have there, my friend, is a leaking power booster which I would replace ASAP for the sake of the kid chasing his ball. Seriously, they're not hard to replace and cost around $80.

    The learning curve is a toll road...ride with someone who has already paid!
    <a target="_blank" href=http://photos.yahoo.com/abshort1>My Naval Fleet</a>
     
  8. backlash

    backlash 1/2 ton status

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    Alan,

    How sure of this are you? I had the dealer replace the vacuum booster last year ... didn't correct the problem. A few months ago it was in there again and they said the booster was bad. When I told them to go ahead and repalce it (it's under warrantee) they said OK ordered it and now say after disassembling it the booster is not bad, put it back together and said it was normal.

    Any ideas?
     
  9. BorregoK5

    BorregoK5 1/2 ton status

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    I had similar problems with my vacuum booster(s) before I swapped in a hydraboost. There was an option for a stock hydrabooster on some 1 ton chevy/gmc trucks more commonly known as the Heavy Duty Brake package. I haven’t seen it on K5’s but found mine on a 79 K10 1 ton. The booster has a direct bolt on replacement with a slight modification to the booster bracket ( use a hammer to tap out the 2 center studs on the bracket so you have six holes matching the firewall), I had to shorten the booster pushrod which lies between the booster and the master cylinder by a couple of inches (hyrda one too long and vacuum one too short) and purchase a few high pressure hoses to complete the system (one from the power steering pump to the hydrabooster and one from the hydrabooster to the steering box). There are some out there, which have independent high-pressure lines, but they require the replacement of the pump with the correct fittings.

    Here is the thread with the prices and part numbers -
    <a target="_blank" href=http://coloradok5.com/forums/showflat.php?Cat=&amp;Board=blazer4x4&amp;Number=235896&amp;page=&amp;view=&amp;sb=&amp;o=&amp;vc=1>http://coloradok5.com/forums/showflat.php?Cat=&amp;Board=blazer4x4&amp;Number=235896&amp;page=&amp;view=&amp;sb=&amp;o=&amp;vc=1</a>

    "I'm looking for a Dana60 Front Axle.." I asked, "You wish! HAHA" the wrecker replied! - <a target="_blank" href=http://www.echobit.com:81/k5/> Pictures</a>
     
  10. Burbinator

    Burbinator 1/2 ton status

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    Fairly sure. I had the same exact problem with my '82. Does the "whoosh" sound continue when the brakes are applied (i.e. at a light)? Mine did that and the idle quality went south as a result of the leak; ran OK in park or cruise. I'd say go to another dealer. Vacuum leakage sounds and inches of travel are never "normal". Something is bad or misaligned somewhere. Also, check the vacuum line from the carb the the booster, as well as the check valve.

    Sorry to intrude on your post Mudnutt...

    The learning curve is a toll road...ride with someone who has already paid!
    <a target="_blank" href=http://photos.yahoo.com/abshort1>My Naval Fleet</a>
     
  11. backlash

    backlash 1/2 ton status

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    &lt;&lt;Does the "whoosh" sound continue when the brakes are applied (i.e. at a light)?&gt;&gt;

    No, I only hear it when the pedal is depressed( needs Paxil). I did a thread on this a while back ... some breatheren say they have the same sound, but I just don't think that when this is cold, it is safe. I can slam on the brakes, with both feet even and it doesn't lock the front up ... slow to stop.
     
  12. Burbinator

    Burbinator 1/2 ton status

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    Hmmm...I'm no expert on brakes, all I know is my personal experience with them. Perhaps another member knows what it is? Air/water in the lines, proportioning valve...just shooting ducks here.

    The learning curve is a toll road...ride with someone who has already paid!
    <a target="_blank" href=http://photos.yahoo.com/abshort1>My Naval Fleet</a>
     
  13. BadDog

    BadDog SOL Staff Member Super Moderator Author

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    Sounds like a booster to me. I would see another dealer.

    Bad Dog

    85 K30 CUCV, 350 TBI, TH400, 205, D60/C14, 4.56 Locked
    Some day: 4" lift, 44" tires, massive cutting, shorter wb and rear overhang.
     
  14. MUDNUTT

    MUDNUTT 1/2 ton status

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    borrego, i got mine off an 84 or 85 diesel pickup. i didnt have to do anything to the pushrod, it hooked right up. the only real problems i had were the pump and the pressure line at the box. the pump i used was also off the diesel and the bracket was diffrent. took the bracket off the old pump, ground on it a little and bolted it to the diesel pump. my box has the flare ends on the lines and the hydoboost had the newer o-ring ends. what i did was cut off the o-ring end on the pressure line from the hydro to the box and the flare end from the old line and joined them with a compression fitting. its holding so far. if it starts to leak i'll get a new hydraulic hose made at nappa
    deck

    <font color=blue>DRIVE IT LIKE YOU STOLE IT[​IMG]
    <font color=red>PROUD TO BE AMERICAN[​IMG]
     

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