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Problem with rear drum brakes, I'm out of ideas.

Discussion in 'Engine and Drivetrain/Mechanical' started by msell66, Jul 19, 2018.

  1. msell66

    msell66 Burning Fossil Fuels Donator

    So, I changed from the stock 10x1 3/4 drum brakes to 11x2 1/4 last year. New everything including the backing plate. Since installation, I've had this same problem.

    When I put the drum on the axle hub and then snug up the brake shoes so they just start to get drag, I can easily spin the axle with my hand. If I either tighten the drum down with lugnuts only of wheel and lugnuts, I can no longer turn the axle or tire by hand.

    Things I've checked:
    Axle flange runout checked out less than .003"
    Axle is square to the flange
    New axle bearings
    Drums have been turned
    Shoes sit fine depthwise into the drum. They are not touching the drum anywhere except the shoe face.
    The shoes are the correct radius and fit the drums perfect.
    I've used white chalk everywhere to see if there is rubbing. No witness marks other than the shoe face.

    If I adjust the shoes in at the bottom so that when tightened down it does not affect turning by hand, the brakes don't do squat when the brake pedal is pressed. If I do adjust the shoes so they have the correct drag and then tighten them, I get major brake fade pretty quickly on track and the drums get super hot.

    I have yet to check if the backing plate is square with the axle flange. That is the last thing I can think of to test. I've discussed this with John at ORP and he said no one else has had this problem with this larger brake kit.
    I realize that due to the drugs I've had over the last 3 years, I'm limited in my ability to diagnose problems. So now, it's up to yoose guys!

    [​IMG]
     
  2. tarafied1

    tarafied1 Well-Known Member

    It is the same on both sides? The problem I mean.


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  3. B67FSTB

    B67FSTB The NorCal dude from Belgium

    Maybe your drums are oval ? Put them on a lathe and see if they are round .
     
  4. msell66

    msell66 Burning Fossil Fuels Donator

    Yes


    Mark
     
  5. msell66

    msell66 Burning Fossil Fuels Donator

    Drums have been turned/trued.


    Mark
     
  6. B67FSTB

    B67FSTB The NorCal dude from Belgium

    Drums are turned I see.
    Are all 4 brakeshoes the same ?
    Sometimes the front faced brakeshoes ( the rightone on the right side and the left one on the left side ) are the one with the lesser friction plate.
    comprende ?
     
  7. msell66

    msell66 Burning Fossil Fuels Donator

    Porterfield R4 shoes. All the same. No front or back.


    Mark
     
  8. B67FSTB

    B67FSTB The NorCal dude from Belgium

    Axles itselfs ?
     
  9. Midlife

    Midlife Well-Known Member Staff Member Moderator

    Brakes on the wrong side?
     
  10. steveh326

    steveh326 Member

    only thing I could think to try is maybe some blue tape on all potential sources of the interference, reinstall the wheel then remove and see if there are any indication on the tape of where it is happening?
     
    msell66 likes this.
  11. tarafied1

    tarafied1 Well-Known Member

    Is it only when lugs are torqued? If they are just finger tight dies it do the same?


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  12. David67

    David67 Active Member

    Buy a new drum and put it on to see if it still drags. Maybe it's the design of the drum?

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  13. msell66

    msell66 Burning Fossil Fuels Donator

    Checked by local performance shop. Ok


    Mark
     
  14. msell66

    msell66 Burning Fossil Fuels Donator

    Even tightened by hand with three nuts locks it down.


    Mark
     
  15. msell66

    msell66 Burning Fossil Fuels Donator

    Tried that. Same result.


    Mark
     
  16. msell66

    msell66 Burning Fossil Fuels Donator

    No


    Mark
     
  17. tarafied1

    tarafied1 Well-Known Member

    do you have pics of the inside and outside of the drum(s)?
     
  18. kb3

    kb3 Well-Known Member

    Without re-reading everything, are the drums dragging on the backing plate?
     
  19. tarafied1

    tarafied1 Well-Known Member

    couple more questions:
    Do you have a parking brake?
    If so can you cause the wheel to lock up with parking brake set, when shoes/adjuster is set to spin freely while lugs are tight?
    Do you have an adjustable proportioning valve?
    can you set the shoes/adjuster to spin freely and adjust the proportioning valve to give more rear pressure? And by doing so, then cause wheel to lock up when brakes are applied but still spin free when not applied?
     
  20. msell66

    msell66 Burning Fossil Fuels Donator

    No


    Mark
     

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