Having a hella'va time with my brake shoes

[richarddacat]

K75c rear drum brake.
Went to change the tire and shoes popped off taking the wheel off.
The two shoes are not alike and they shouldn't be, one is smaller and it appears that it won't fit. I've tried several times, every which-a-way and it doesn't make sense to me and rubs the wheel when its installed. The worn spot on the cam shows the shoe had fit there before, but damn if it does now.


The lower cam doesn't touch the smaller shoe. It worked before, WTF am I doing wrong? My shop manual doesn't have a good picture of the assembled shoes before the wheel goes on. Does anyone have a picture of this or direct me to one??


I've looked at a parts fiche to make sure I have right shoes but it doesn't give each part number, they look the same as I got anyway. I'm almost positive that they have never been changed.


Get frustrated....needing to vent.  :nono

[Laitch]

This is from an online Haynes manual. Forward is toward the left. Notice the different shapes of the lower parts of the shoes.

[richarddacat]

Thanks, same as the one in my Haynes. Looks like I have a different shoe. Odd though. Besides locking up easily they worked.
This is what I got.
This is the part numbers -34 21-1235 693 & 694


Going to contact a dealer to see about part numbers.






This is what you get now 'n days, looks like my shoes.

[Laitch]

]Thanks, same as the one in my Haynes. Looks like I have a different shoe.

Nope. Jeezum Crow! Look at the picture and flop the two shoes so the right is on the left and the left is on the right. Try that then they'll look like the illustration and the halftones. You know what flop means?

[richarddacat]

Nope. Jeezum Crow! Look at the picture and flop the two shoes so the right is on the left and the left is on the right. Try that then they'll look like the illustration and the halftones.

Well, I've done that and the flats on the shoes don't match the flats on the cam.
Hang-on I'll try again.

[richarddacat]

[Laitch]

Now the shoes' positions look like their illustration. There should be two springs—one upper and one lower. What happens when the pedal—or rod, if it isn't connected to the pedal—is actuated?

[richarddacat]

Notice where the cam is. Pushing the brake arm on the drum back, activates the shoes to expand but it needs to expand pulling fwd.


Putting the bottom spring on rubs the shoe in the above pic.


I've now took the brake arm off moving the cam around but I'm still not getting it. Desperatelly like to see a picture of one working.


part numbers are correct.

[Laitch]

Pushing the brake arm on the drum back, activates the shoes to expand but it needs to expand pulling fwd.
Desperatelly like to see a picture of one working.

When shoes expand, they expand outward. What's pulling forward mean?
Don't get too desparate. :giggles  It's all trial-and-error, and patience.

I've now seen the shoes assembled in either position—left or right. So you can put them back to their previous position and try again with both springs installed. I haven't found shoes with that part number though. Are those numbers on the shoes? Did you get the set from MAX? When the shoes were in the previous position, did the lower spring fit? Do the cam lobes look worn?

I think you should clean up that backing plate; the shoes are starting to look old before their time. :giggles

[richarddacat]

Max BMW confirmed the part numbers, the numbers are on the shoes. You can only get the kit now as in the pic above, Max had one in stock and looked for me to confirm. Great folks there.  :clap:


Pulling fwd means when you step on the pedal it pulls the brake arm fwd, not back.


This is whats weird, the cam shows wear on the flat surfaces but I can only get one shoe, the long one to the fit on the flat part if the cam.


About ready start over tomorrow.

[Laitch]

You should push the lever arm in the direction that the pedal would make it move.

Put the shoes in the first position you had them.  The bottom spring should be able to be installed then. Try to set the cam's lobes at 10 o'clock and 4 o'clock so rear (upper) shoe will be contacted by the cam first then the front (lower) shoe will be contacted with a stronger rod pressure.

[richarddacat]

I'm done, fuc'ing brake shoe broke in half.  :musicboohoo:


I'll have time WAITING ON PARTS!!!! to clean the back plate now.

[Laitch]

Let's play a duet. I've run out of french fries.  :musicboohoo:

[caveman]

I just got strawberries

[richarddacat]

Well, all I needed was a new pair of shoes and a day off.
Went back together without a hitch.


All I can figure is the camshaft wasn't in the correct position at my first attempt. As mentioned above the part numbers are correct, old shoes and new shoes matched up. The shoe that broke was apparently from me fighting with it, I guess, who knows.
Time and patients ruled the day.

[johnny]

greetings...

tremendous... now go free willy...



j o

[richarddacat]

Well, I finally got a ride in and will have to say my rear brake is pretty awesome for a 1988 shoe and drum brake. Doesn't lock up like before, very smooth and well controlled.  :2thumbup: