Page 1 of 3 123 LastLast
Results 1 to 10 of 22

Thread: Warning - Smart 450 Brake Shoe Set

  1. #1
    Join Date
    Nov 2007
    Location
    BANCHORY
    Posts
    3,092

    Warning - Smart 450 Brake Shoe Set

    What is wrong with these?

    ATE:


    Bolk:


    Bosch:


    Febi:


    Hella:


    TRW:


    Drives a Smart Cdi - 65 to 85 MPG

  2. #2
    Join Date
    Apr 2009
    Location
    Ecosse
    Posts
    3,461
    Wrong distribution of lining (shouldn't be so close to shoe end at end of shoe that mate with cylinder)?

  3. #3
    Join Date
    Nov 2007
    Location
    BANCHORY
    Posts
    3,092
    Wrong.
    One of above shoe sets are assembled correctly. So is also mine pictured below.

    Drives a Smart Cdi - 65 to 85 MPG

  4. #4
    Join Date
    Nov 2007
    Location
    BANCHORY
    Posts
    3,092
    The problem is that unlike us, the manufacturers are not sufficiently smart thereby bewildering some owners and most unskilled mechanics.
    Drives a Smart Cdi - 65 to 85 MPG

  5. #5
    Join Date
    Nov 2007
    Location
    BANCHORY
    Posts
    3,092
    I have seen at least half a dozen Smarts with this problem. Long brake pedal travel caused by wrongly fitted brake shoes.
    The adjuster mechanisms are marked left and right (G, D, L, R depending on where made). Left and right here refers to whether mechanism has left or right hand threads, not which side they are to be fitted on the vehicle.
    Adjuster with right hand threads fits on left side shoes.
    Adjuster with left hand threads fits on right side shoes.

    Why is this important? You try figure it out.
    Drives a Smart Cdi - 65 to 85 MPG

  6. #6
    Join Date
    Apr 2009
    Location
    Ecosse
    Posts
    3,461
    Because the rotational direction imparted varies side to side as it is mounted differently in plan view - ie symmetrically viewed in plan and would be asymmetric in the same view if similar threads were to be used on both sides. Do I get the coconut?

  7. #7
    Join Date
    Nov 2007
    Location
    BANCHORY
    Posts
    3,092
    Linings are correctly positioned on trailing and leading shoes if that is what you are wondering about. Of course it is possible to fit hand brake lever arm on wrong shoe but that is not the case here.

    The problem is the manufacturers fit the adjusters incorrectly. Leaf spring on each adjuster then jams against corner of wheel bearing mounting flange causing adjuster mechanism malfunction.
    Quite a serious issue in my humble opinion.
    Drives a Smart Cdi - 65 to 85 MPG

  8. #8
    Join Date
    Apr 2009
    Location
    Ecosse
    Posts
    3,461
    Linings are different compared to the pic on Evilution though. Which I assume is a pic from the early days of smarts.

    Not sure I have my handbrake sticking sorted. Shifted from one side to the other and was a proper PITA at MOT. Haven't been probing as to ascertain if it has released requires stopping again - and I won't get much miles done like that. The prospect of overheating a brake and risking a fire has little appeal either.
    Given it originated when the connection at the subframe was disturbed, I'm more inclined to think the fault is there. But loath to drop the subframe for such a trifling problem. Perhaps from above after lifting the carpet. Any ideas?

  9. #9
    Join Date
    Nov 2007
    Location
    BANCHORY
    Posts
    3,092
    Only the Bolk brake shoes are different. All others are copies of the original.

    Yours are overheating? Likely to be stiff hand brake cables assuming that you are sufficiently smart to have fitted your brakes correctly and that you have not manually over adjusted the adjusters.


    Above is a view nearly vertically up of inboard end of hand brake cable. Forward engene mount can be seen on left side of photo. Note that inboard end of hand brake cable is held on with a metal spring clip. Access to it is normally impossible unless subframe is lowered.

    Releasing inboard end of hand brake cables are tricky unless one has special skills and a special tool.

    Suggested releasing procedure for inboard end of hand brake cable:

    1) Release cable inners from hand brake equalizer plate.
    2) Fit special release tool over hand brake inner, pull down whilst wiggling to release/ compress steel catches.
    3) Pull down on hand brake cable perhaps wiggling it if seized due to rust.




    Pipe bore 10.5 mm. Pipe length 13 mm. Pipe wall thickness 1.5 mm. Tool overall length 265 mm. Round bar diameter 6 mm. Square handle size from centre line to centre line of round bar 52 x 57 mm. Dimension of L shaped part of round bar from square handle to outer circumference of pipe 200 x 18 mm. Painted in Lidl's best release tool enamel.

    Adding below line diagrams for completeness:


    Right hand side Bosch Bendix drum brake assembly as fitted on a Smart 450.


    Right hand side Bosch Bendix automatic brake adjuster. Note that the threads on the adjuster screw (16) are drawn incorrectly in the line drawing. Right hand side automatic brake adjuster has left handed threads whilst left hand side automatic brake adjuster has right handed threads.
    Drives a Smart Cdi - 65 to 85 MPG

  10. #10
    Join Date
    Apr 2009
    Location
    Ecosse
    Posts
    3,461
    Not overheating - but if they fail to release and I drive they could.
    Cables are free enough and the brake assemblies haven't been disturbed from when they worked fine. It feels like it always did throughout its life - from nearly new.

    On raising subframe, after a struggle to get the rod to enter its slot - it kept raising the handbrake lever - first one brake was sticking but I could get it to release just by juggling the throttle. It appeared to have adjusted itself up and I had to manually back off the adjuster to remove the drum - which has never been a problem before and the drums aren't grooved. Then the other side started sticking but the drum removed easily enough. Both sides cleaned and during MOT handbrake was obviously given a really good tug and then the NS (the first to be troublesome earlier) would not release - even after blows with a hammer to the drum. Six miles later it had freed.

    While attempting to get the rod into the slot during raising the subframe I pulled on the long thin (guide?) rod that is central in the mechanism. Could that be the cause? Since MOT I've avoided using the handbrake for the previously mentioned reasons. It's going to need fixing at some point though.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •