Hydroboost conversion questions

Discussion in 'General IH Tech' started by gillis51, Oct 14, 2010.


  1. Bill USN-1

    Bill USN-1 Moderator Staff Member Moderator

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    You may want to read my original write up since most info gets thinned out as it gets repeated on here 10-20 times.
    Go to justih site and look for any write up I did. There are links at the bottom of each to the writeups.
     
  2. scorp1us

    scorp1us High Wheeler

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    16mm, 18mm wrench for the hoses.
    15mm DEEP socket. for the mounting bolts under the dash.
    Bring an extension or two too.
    Something to cut the brake lines after the prop valve. (Reuse metric fittings)
    That should be it. Take a few extra wrenches just in case.

    Using the above tools, remove the hoses from the unit. Cut the brakes lines after the valve. Remove the 4 nuts from under the dash. Pull unit from engine bay. It's just that easy.

    EDIT: I do have a question With the stock astro van MC and reservoirs, how do I fill/bleed them? They have a rubber insert. What is this for? Do I pour fluid on in it, or under it? I've never seen this before.
     
  3. vegestar

    vegestar Binder Driver

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    I followed Bill's write up, made things wicked easy! All of the issues that come up are covered such as the different power streering pressure line fittings and shimming the pump to raise the pressure a tad. My truck is a 1980 so I have the o-ring fittings already, I used the master and prop valve from the Astro, and fitted a spacer (a temporary one made of wood) between the firewall and Hydro unit. Brake lines were a cinch, a little bending here, a $3 fitting there and walla!
     

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  4. gillis51

    gillis51 Binder Driver

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    This site and others like it are great. I bought my first scout about 7 months ago and if it hadnt been for all the great posts & info on theses sites i probably would have never bought one. Thanks for the help.
     
  5. vegestar

    vegestar Binder Driver

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    Well, this site is special! I have never seen a more supportive and polite collective of members. I spent a little time on a TDI forum doing some research for a job I am working on, those guys are a bunch of ruthless pricks! I had to get outa there before I got contaminated, I mean, everyone is entitled to their opinion but that doesn't mean I want it stuffed down my throat... The point is, I love it here and I haven't even driven my Scout yet. And I'm thinking about building another one just so I have something else to talk about here. Good luck with your truck and welcome to the family.
     
  6. scorp1us

    scorp1us High Wheeler

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    The average age here is way up there. I think I am one of the younger ones at 33. Also the vehicle's aesthetic seems to attract a more mature crowd. I used to have a 2000 eclipse and that forum was hell too. I wonder what the board average age is? I think the eclipse forum was about 24... We're easily clearing 34 I bet.
     
  7. scorp1us

    scorp1us High Wheeler

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    Well I got the Hydroboost on and tested last night. I have to say... WOW.

    I did not do the pump upgrade but pedal pressure is light. I can effortlessly stop the thing as if it was my sports car. I can now stop without gliding to a halt (I could have had booster issues before I had my catastrophic booster failure)

    I did notice a couple quirks:
    The pedal return is a bit slow. I am wondering if this is because I should set the pedal lower, back to stock so the spring has more effort. I'll probably add another 0.5" to the spacer (already 1.0"), so it just pulls the pedal back to the floor more.

    The larger brake line fitting can be taken from your stock proportioning valve.

    I went with my custom hoses (#6 and #7AN) fittings. Pics to come.
     
  8. vegestar

    vegestar Binder Driver

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    Congrats on gettin er done! Did you notice any difference with the steering? I used to drive my uncles old dump truck and both brakes and steering would fade if used at the same time! Even after we replaced the PS pump and hydroboost. I've heard nothing but good things about this conversion though (or else I wouldn't have done it) but my only experience has been with that old truck, just curious.

    I agree that age and maturity level play a part in this forum's helpful family atmosphere, would be interesting to know the average age here vs other sites. I know there are a lot of younger guys (and gals) here but I think they got brainwashed to our polite and considerate ways... Sometimes I feel like we (I'm 28) fall into a sort of generation gap between the older guys that have had their trucks since they were a kid and the kids that just got them! lol
     
  9. scorp1us

    scorp1us High Wheeler

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    There is some peculiarity of using both at once. I guess you could call it a fade, though only slightly. Not enough to impact braking consideration. (Meaning my foot can compensate automatically)
     
  10. Bill USN-1

    Bill USN-1 Moderator Staff Member Moderator

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    If there is a difference then you need to look at the plumbing.
    The return must be free flowing so either use a thin walled Y or T with the brake return on the straight side.

    If you try to use brass fittings they are to restrictive since the ID is so much smaller then the OD.

    I ended up adding a seperate return port to the top of the pump can so both have a free return.
    Many later pumps already have both.

    Always run a cooler like a small tranny cooler.
     
  11. IH64Scout

    IH64Scout Dreams of Cub Cadets

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    I don't have any cooler and have not had any issues. Guess that'll be something to add to the list this winter. I attempted the shimming of the pump using 2 .030 shims and I split 2 p/s pumps in half!!:confused: I'm thinking of trying it with only one. With the 2 the steering was SWEET, one finger to turn 37s aired down to 10 psi. Just as soon as I hit locks POP and hard steering! And I guess I'm a youngin, I'm 22 now and I've been here a while!

    -Jon
     
  12. Randy Z.

    Randy Z. Binder Driver

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    When I did mine I asked Lee Manuf. about availability of the shims. They recommended that I swap out the flow valve along with the pressure valve rather than shimming. I ordered them as well and haven't noticed an issue with braking while steering or vice-versa.
     
  13. IH64Scout

    IH64Scout Dreams of Cub Cadets

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    where did you get it??:confused:

    -Jon
     
  14. scorp1us

    scorp1us High Wheeler

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    Well I am using a 0.5" brass T, perfectly situated for return from the booster. (maybe a Y would work better?) but I'm barely noticing anything, if I do notice anything. I don't know why we'd need to run a cooler when the stock systems didn't.

    I didn't bother to shim my pump, and effort is lighter than my sports car.
     
  15. Randy Z.

    Randy Z. Binder Driver

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    Lee Manufacturing - The company that sells the ferrules to use the JIC type hoses on the o-ring booster. See Bill's write up.
     
  16. Bill USN-1

    Bill USN-1 Moderator Staff Member Moderator

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    Well if you drive your astrovan/scout to the mall then you won't need a cooler. So when you say you have not had any issues....how many trails have you run?

    But I assume we own IH 4x4's and actually use the upgrades offroad.
    So when your crawling around at slow speeds with your foot on the brakes and the front wheels against the side of rocks and roots, things will heat up. I'm sure this was discussed in the original write up.

    And the hydroboost isn't what caused me to use a PS cooler. I have boiled the fluid out just wheeling with stock steering. So I went to a cooler and I run valvoline synthetic fluid that has a higher boiling point.
     
  17. IH64Scout

    IH64Scout Dreams of Cub Cadets

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    wow, all the wheeling i do with 37" tires i've never had an issue with overheating fluid... :cornfused: i guess it wouldn't hurt though!

    -Jon
     
  18. Bill USN-1

    Bill USN-1 Moderator Staff Member Moderator

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    All those creeks you drive thru keep it cool!:D

    Guess you need some tougher trails.
     
  19. IH64Scout

    IH64Scout Dreams of Cub Cadets

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    haaha i agree..to both! :D

    -Jon
     
  20. vegestar

    vegestar Binder Driver

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    Ya, you've been here longer than me I think, and you've certainly accomplished more than most. The best part is watching you break it and fix it all over again. lol Have you really gone through two pumps? Good thing they are cheap and plentiful!

    I am installing a cooler on mine as well, I mean why not, especially when it's free. Almost every newer vehicle that is built halfway decently has one.
     

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