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Brake Information & Adjustment Procedure

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  • Brake Information & Adjustment Procedure

    Brake Adjustment Procedure:

    I've noticed posts about sticking brake pedals and poor brakes on other sites where I no longer post . If the brake rods are not set up correctly , the brakes will be poor even if all parts are new . Here is how I do mine . I first adjust the brake adjustment wedges at each wheel with the brake rods disconnected at the clevis end . I start by adjusting the wedges at the rear wheels . Because of the design of the rear wheel bearings and bearing races, wear will effect rear brake adjustment . In other words if the rear brakes are adjusted with the rear axle on stands the brakes will often be WAY TOO tight with the wheels on the road . I first adjust the rear wheel brakes with the wheels on the shop floor where the wheels support the weight of the car with all brake rods disconnected . It is important that the tires are fully inflated so that they can roll easily with less resistance . The average guy should have the strength to slightly roll the car by the back bumper , back and forth to feel the drag when the rear adjustment wedges are tightened . When the desired drag is obtained ,iback off the adjustment as needed . I then proceed to the front brake adjustment with the front axle on stands . If all is good the front brake levers should lean foward about fifteen degrees. Sometimes brake pills-shims may be needed at the front lower brake wedges to obtain the foward lean on the front brake levers . I then proceed to the service brake cross shaft and pedal set up .It has often been said that the levers on the cross shaft should point straight up and down . To acheive this adjustment the plunger end of the pedal rod , where it meets the brake light switch should be within 1/16 inch from the inner rear of the center crossmember on 30-31 models where the brake light switch attaches . The brake light switch mounts in a different place on 28-29 models but the plunger on the pedal shaft should have the same1/16 inch clearance between the plunger and the inner rear side of the center crossmember . I now proceed to adjust the clevis on the pedal rod so that the pedal will be at the top of its travel , now prop the pedal up in place . I then adjust the clevis at the end of the service brake rods so that the clevis pins will just penetrate through the brake rod clevices and the brake levers . The levers need to be pulled backwards on the front levers and foward on the rear levers to remove ALL slack when the clevice pins are installed . When the brake rods , brake pedal and service brake cross shaft is set up in this manner with all slack adjusted out , the brake lining will be ready to meet the drum with the slightest depression of the brake pedal for best brakes. The early 28s before separate emergency brakes were added were different . The early brake rods were not adjustable and were made to a specific length that doesn't apply to the later model A brakes .


    By Jim Mason:

    Good article in tech section. I'd like to add one correction, the brake rods on the VE and early vehicles were adjustable. the non adjustable rods were used May to Nov
    2 1930 Tudors

    Henry Ford said
    "It's all nuts and bolts"


    Mitch's Auto Service ctr

  • #2
    Resurfacing Brake Drums Info!


    I have an ammco 4000 brake lathe,
    resurfacing / truing the front drums is no problem as the 1" arbor and standard race adapters work beautiful. The issue is the rear drums as the 1" arbor will not slide through the end of the hub because it has a 3/4" opening. After doing a little research i found that ammco sells an 11/16th" arbor which comes with all needed accy's. This setup will adapt to any ammco Models 2002, 3000, 4000, 4100, 7000, 7700 brake lathes. So for anyone looking to be able to do the rear drums a brake doktor is not needed. these ammco machines are easily available used and for good prices. Just thought i would post this info as i hope it can help.
    The part # for the kit is 9708 and i found the cheapest place to buy it from with free shipping, and dropped shipped from ammco, so it only took a few days to get


    IMG_6201.JPGIMG_6202.JPGIMG_6203.JPG
    Attached Files
    2 1930 Tudors

    Henry Ford said
    "It's all nuts and bolts"


    Mitch's Auto Service ctr

    Comment


    • BILL WILLIAMSON
      BILL WILLIAMSON commented
      Editing a comment
      WAAAH, I only had a piddly AMCO 2000, but it had the adaptor you show. I made lots of $$$$$s with it, doing drop off DRUMS/ROTORS.
      Dad Poor

    • Mike
      Mike commented
      Editing a comment
      Mitch good to know you have the machine that can cut rear drums. Some of the new cast iron drums need to have 1 more finish cut.
      mike

    • Tom Wesenberg
      Tom Wesenberg commented
      Editing a comment
      When I did the brakes on my 62 Chevy I was able to turn the drums on my 12" Atlas lathe. I remember using an Ammco at the GM dealership I worked at in the 70's, and it was a nice machine. A few times I'd hit hard spots in the drums. I'm not sure what caused them, but they sure needed a sharp new carbide to clean them up.

    • tbirdtbird
      tbirdtbird commented
      Editing a comment
      I've noticed hard spots in just about any metal I have ever worked with. I just had to machine a billet (2x2x12) of 1045 Tool steel to make a brake arm for my '47 Stude M5 project and was a little surprised that it too had hard spots. I guess no alloy is totally uniform

    • Mitch
      Mitch commented
      Editing a comment
      Hard spots or glazed spots in the drum. These are caused by excessive heat that brings about metallurgical changes in the metal. Hard spots can be identified by raised or discolored patches on the drum friction surface. Hard spots can cause chatter, pedal pulsation and grabbing when the brakes are applied.

    • BILL WILLIAMSON
      BILL WILLIAMSON commented
      Editing a comment
      SOME lathes have a GRINDING attachment, that does well on HARD spots.
      OH, spade the GRINDINGS/CUTTINGS around your ROSES & you can SHOW your blossoms (REALLY!)
      Dad Hortiguru

    • Terry, NJ
      Terry, NJ commented
      Editing a comment
      As a machinist apprentice, I was taught that in steelmaking a lot of scrap is used and there's no attempt to sort it by type. In other word when a car, refrigerator, washing machine, what have you, it all goes in the crucible and gets melted together. Consider what's swimming in the mix! HRS, CRS, forgings bearings and yeah, this does cause hard spots that glaze tools. No amount of annealing or "Normalizing" will eliminate this because the steels are of a different composition. They are in their softest state. Another reason why welders and machinists say the old stuff is better to work with. It hasn't been through the foundry yet.
      Terry

  • #3
    Check the Articles Forum for the Evolution of the Model A Brake Shoe

    https://www.vintagefordforum.com/art...teve-c-plucker
    2 1930 Tudors

    Henry Ford said
    "It's all nuts and bolts"


    Mitch's Auto Service ctr

    Comment


    • #4
      Brake Operating Wedge Cross Section

      Provided By Brent Terry


      brake.jpg
      2 1930 Tudors

      Henry Ford said
      "It's all nuts and bolts"


      Mitch's Auto Service ctr

      Comment


      • #5
        Brake Floater Discussions:

        https://www.vintagefordforum.com/for...hurts-the-most

        https://www.vintagefordforum.com/forum/model-a/27497-flathead-ted-s-brake-floaters
        2 1930 Tudors

        Henry Ford said
        "It's all nuts and bolts"


        Mitch's Auto Service ctr

        Comment


        • #6
          Rear Brake Assembly



          F98470E4-ECB7-478B-B240-D0F61FC78463.jpeg18CFCF29-2535-4586-8EC9-89E0AF0103B9.jpeg0EE2CD70-302B-40A5-9D54-7E2EEE99B77F.jpeg
          2 1930 Tudors

          Henry Ford said
          "It's all nuts and bolts"


          Mitch's Auto Service ctr

          Comment


          • Beauford
            Beauford commented
            Editing a comment
            Looks too clean...I don't trust it. LOL

        • #7
          Front Brake Assembly


          AE329164-D8C2-439B-A962-86927321C9EA.jpeg542A0050-282F-458D-9196-CFDC978AB6A9.jpegA5B9DE6B-D96D-4165-9E2C-E2528206105C.jpeg
          2 1930 Tudors

          Henry Ford said
          "It's all nuts and bolts"


          Mitch's Auto Service ctr

          Comment


          • #8
            Front operating pin felt positioning


            7BEB5660-5E37-40A1-9FDB-E7E2E024E51C.jpeg

            2 1930 Tudors

            Henry Ford said
            "It's all nuts and bolts"


            Mitch's Auto Service ctr

            Comment


            • #9
              With the goal of have fully functioning, safe brakes, how we achieve that is subject to different approaches. I'd like to add mine.

              With the brake rods disconnected , car off the ground, set the brake pedal & rod to cross shaft so the shaft is vertical.

              At this point screw the brake adjusting wedges in to a point where all four wheels are locked. Now adjust and install the brake rods. (I prefer to use hitch pins at this point)
              Now I adjust the brake/ wheel drag. (After 80 years of brake service there may be any issue with adjusting the rear brakes off the ground, but at 70 I'm not sure I need to be pushing a car.)

              Lower the car and road test to make any minor adjustments. Finished, install correct cotter pins.

              Sometimes a car will pull slightly. Using hitch pins, remove the pins from the front bakes and CAREFULLY road test. Now reverse, install the front hitch pins and remove the rears and again CAREFULLY road test. This method will quickly determine which brake is the problem ( Thanks to Don Turley for sharing this last suggestion.)

              Hope some find this helpful, JB





              Comment


              • Mitch
                Mitch commented
                Editing a comment
                So when you mention car off the ground, you mean supported under the axles not the frame correct?

            • #10
              With all the paint fumes in my garage, everything levitates........

              Comment


              • Mitch
                Mitch commented
                Editing a comment
                I also use the hair pins clips for temporary use when setting up the adjustments

            • #11
              Referring to my picture, 'What are hair pins ??'

              Comment


              • #12
                Originally posted by JB-OB View Post
                Referring to my picture, 'What are hair pins ??'
                2 1930 Tudors

                Henry Ford said
                "It's all nuts and bolts"


                Mitch's Auto Service ctr

                Comment


                • #13
                  Grinding a 15 degree chamfer about 1/4" in on the front brake shoe diameters allow easier assembly of the drums before adjustments.

                  Larry Jenkins

                  Comment

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