Quick and dirty Z bar bushing fix

Discussion in 'Wrenchin' Secrets' started by CJay, Aug 23, 2018.

  1. CJay

    CJay Supercar owner Staff Member

    So what do you do when you rubber Z bar bushing falls apart and you want to go to a car show? Improvise!

    So Im driving the Aquamist car and the pedal is grabbing right off the floor which is unusual. A quick check under the hood reveals that the Z bar bushing is destroyed. The upper clutch rod is essentially pushing against the shell of the old bushing. And I have no new bushings in stock. Crazy talk right?


    KIMG1616[1].JPG

    So what to do? Turns out a piece of scrap 5/8" heater hose is a perfect fit! I cut the piece of hose about the width of the bushing shell and stuffed it in. Then I tapped the inner metal tube of the old bushing into the hose. Perfect fit.


    KIMG1618[1].JPG

    Slammed the Z bar back in the car and the pedal is back! Im half thinking to just leave it the way it is it worked so well! And it literally cost nothing. Winning!!:D:p


    KIMG1617[1].JPG
     
    BYoung and Brett Slater like this.
  2. Taulbee2277

    Taulbee2277 Silver Level contributor

    Nicely done! And now you have multiple feet of bushing stock just in case.
     
    Brett Slater likes this.
  3. STAGE III

    STAGE III Lost Experimental 455-4 Bolt Main Block.

    Cheap yet satisfying!:D:)Thanks for the tip !
     
  4. Briz

    Briz Founders Club Member

    WTG dude! I love doing stuff like that.
     
  5. yachtsmanbill

    yachtsmanbill Well-Known Member

    Glue the bushing in and grease the pedal shaft... dang beaters! Is that a regular cotter pin or a manual shifter linkage clip? The clip will hold it flat against the arm. :eek: ws
     
  6. agetnt9

    agetnt9 Agetnt9 (Dan)

    Necessity,,, The mother of all invention HA !!
     
  7. CJay

    CJay Supercar owner Staff Member

    That's the correct hair pin clip Bill. Im going to pop in a new bushing this weekend. Although it worked so well, it was just supposed to be a temporary fix. Got me out of a jam though. If you drove this car, you'd swear you were driving a new car. All the oblong, worn holes in the clutch linkage and pedal were tig'ed closed and re-drilled. There is zero slop. Same for the shifter and rods. I rebuilt the Hurst shifter with a master rebuild kit and new handle isolators/ clips.

    There's a place by me called LI Corvette Supply that has the GM ones in stock for $7 each. Im going to swing by on my way home from work today and pick up a few, There's also one of these bushings in the fork end of the adjuster rod. I wonder if that one is AFU too? Just for the record, the factory number is 3872955. I wonder if they make these things in polyurethane? That rubber really takes a beating
     
  8. steve covington

    steve covington Well-Known Member

    You could always get some UHMW or HDPE and have a shop make some from stock. Available from Grainger, Mcmaster-Carr, and other industrial suppliers
    Example:

    [​IMG]

    • Color: White
    • Temperature Range: -40° to 180° F
    • Tensile Strength: 2,400 psi (Poor)
    • Impact Strength: 16.8 ft.-lbs./in. (Excellent)
    • For Use Outdoors: No
    • Specifications Met: UL 94HB


    Often used as bushings and bearings, these rods have a slippery surface and excellent abrasion, wear, and impact resistance.

    Dia. Tolerance
    Rating Lengths, ft. Per Ft.
    1/4" Oversized 8701K37 $1.06
    3/8" Oversized 8701K39 1.12
    1/2" Oversized 8701K41 1.18
    5/8" Oversized 8701K42 1.71
    3/4" Oversized 8701K43 1.83
    7/8" Oversized 8701K851 2.05
    1" Oversized 8701K45 2.14
    1 1/8" Oversized 8701K861 3.66
    1 1/4" Oversized 8701K46 3.57
    1 3/8" Oversized 8701K73 4.42
    1 1/2" Oversized 8701K47 4.77
    1 3/4" Oversized 8701K48 6.27
    2" Oversized 8701K49 8.03
    2 1/4" Oversized 8701K51 10.23
    2 1/2" Oversized 8701K53 13.88
    2 3/4" Oversized 8701K54 16.03
    3" Oversized 8701K55 19.08
    3 1/4" Oversized 8701K56 23.75
    3 1/2" Oversized 8701K57 24.64
    3 3/4" Oversized 8701K58 30.00
    4" Oversized 8701K59 33.34
    4 1/2" Oversized 8701K61 43.69
    5" Oversized 8701K63 48.63
    5 1/2" Oversized 8701K65 64.43
    6" Oversized 8701K67 68.03
    6 1/2" Oversized 8701K93 106.07
    7" Oversized 8701K94 170.41
    8" Oversized 8701K95 218.10
    9" Oversized 8701K96 301.91
    10" Oversized 8701K97 355.70
     
  9. yachtsmanbill

    yachtsmanbill Well-Known Member

    The reason I asked was because of the slop on the arm side of the z arm to pedal rod. A thick flat washer may fix that or is the old OEM bushing fatter? I always like making my own stuff too.I have a 9" lathe and could spin you some urethane jobs if you get the material to me. Just sayin'... ws
     
  10. BadBrad

    BadBrad Got 4-speed?

    GM part number 387-2955 -Two per package. Nice work Jason. I always appreciate DIY fabrication stuff. I similarly rebuilt my z-bar and fork with welding, drilling etc., which was very necessary on a 300K+ mile chassis. That upper bushing can be pressed in using the old bolt and socket method with very little trouble.
     
  11. CJay

    CJay Supercar owner Staff Member

    I took the lower adjuster rod out yesterday and as I suspected, that bushing is AFU as well. Im going to tackle replacing both today. And while Im there, Im going to install a different clutch return spring. Since Ive had the car, its had a short spring. It hooks into the hole in the clutch fork clevis pin and goes to the side of the frame. So when you look at it, its off at an angle from the fork. I got a much longer one. Basically the spring portion is the same length, but one side has a super long rod . Im going to try and use the engine crossmember as the new anchor point. That way the spring is in parallel to the adjuster rod.

    I finally got this car pretty much dialed in at this point. I think its a new record too. It only took me 15 years
     
    Brett Slater likes this.
  12. CJay

    CJay Supercar owner Staff Member

    Ok, install complete!

    One thing about these bushings is that they are a little too thick. Here's a picture of the size difference against my spare fork . I used my trusty die grinder and a 3M sanding disc to grind it down until it fit snugly inside the fork. I took a little off each side-

    KIMG1638.JPG


    Another issue is that theyseem to be just a hair too large in diameter. So they press in very tight. I realty don't think its necessary that they be that tight of a fit. They aren't control arm bushings right? So I mounted them on my drill using a long bolt and a nut and turned them down just a little using a file.

    KIMG1629[1].JPG

    They pressed in and out using the old 2 sockets and a vice method (yes, the vice isn't bolted down to the workbench at the moment )

    KIMG1628[1].JPG

    I had to fit the Z bar bushing as well with the die grinder. I kept grinding each side little by little until I was able to get a washer and clip installed.

    KIMG1631[1].JPG

    I installed my new clutch return spring. Its a Dorman assortment that has 4 springs in it. Three of them are heavy duty "linkage benders". But the one is a pretty light duty spring that's perfect. So I put it in and ran it to the cradle. What a difference! Pedal is smooth and clutch grabs right where it should on the pedal again!

    KIMG1632[1].JPG

    I put the old return spring in the glove box next to the Hurst pit pack just in case the new spring doesn't work out unexpectedly

    KIMG1641[1].JPG
     
    Brett Slater likes this.
  13. yachtsmanbill

    yachtsmanbill Well-Known Member

    DANG!!! A STEPHAN vise!! I thought I was the only one with one of them! Did that clutch fork originally have a heim joint or was that a JC special? ws (STEPHAN!)
     
  14. hugger

    hugger Well-Known Member

    Just Another Zbar bushing option, and what I done on my pops car years ago, pressed some bar stock in the holes drilled them out for a GM Oversized bronze door bushing. Easily serviceable if need be and provides a really good feel on the foot. More of a performance oriented option I guess ha.
     
  15. CJay

    CJay Supercar owner Staff Member

    Damn Bill, your good! That is in fact a Stephan vice. Ive never seen another quite like it with the thumb wheel and the handle. My neighbor that lived next door to me growing up gave it to me. I must of been 17 or 18 at the time. It was old 35 years ago!

    KIMG1645[1].JPG

    KIMG1644[1].JPG
     
  16. yachtsmanbill

    yachtsmanbill Well-Known Member

  17. CJay

    CJay Supercar owner Staff Member

    The linkage is all factory/ Big blocks used a fork with a clevis pin on the end similar to a Corvette. The adjuster rod has a big loop in it for one of these rubber bushings. You can see the adjuster rod sans bushing in this mess-

    KIMG0307.JPG
     
  18. CJay

    CJay Supercar owner Staff Member

    I had to thoroughly test drive it today to make sure everything was 100% What a chore:rolleyes::D:D Took most of the day :D

    I took some time in between test drives and machine polished the hood and trunk. The paint looked like it got a bit hazy. Came out pretty good/ Once I was satisfied everything was ok, with the linkage, she got put away. All in all, it was a great weekend!

    KIMG1646[1].JPG

    KIMG1647[1].JPG

    And the Hurst ivory T handle I put on a few months ago when I rebuilt the shifter. Looks so cool!!

    KIMG1648[1].JPG
     
    Brett Slater likes this.
  19. BadBrad

    BadBrad Got 4-speed?

    We've talked about a spherical rod end in place of this thing. upload_2018-8-26_20-23-46.png


    Napa part 732-1129; plus an appropriate exhaust manifold stud.
     
  20. CJay

    CJay Supercar owner Staff Member

    That spherical rod end trick is awesome. But I'm a slave to originality! If anyone has a spare one of those big block adjuster rods, I'd be interested.
     

Share This Page