failed rear brake cylinder...

[richberman]

Well last week I had a nasty scare....one of my rear brakes locked up after using the e-brake on a steep parking incline. I carefully drove it about a mile (to work), stopping about every block for a light or traffic. After 30 minutes or so, I tried to loosen the adjuster screw to back off the shoe but it was stuck. I jacked up the car and tapped on the drum with a hammer and heard the shoes release (great I said). Then I backed off the adjuster 4 flats so it wouldn't lock up again. Drove it another 2 blocks and lost hydraulics completely....brake pedal to the floor.
Luckily I was on level ground and managed to make it home safely by downshifting and e-braking (with just right side working).
Got the drum off last night to find that the ring holding the rubber diaphragm had come off the cylinder, allowing the hydraulic fluid out. Fluid (DOT 4) is now all over the drum and shoes. I have a new cylinder (hate those clips holding it in) and am wondering if I need to replace the shoes and clean the drum or if the shoes can also be cleaned safely. Why would it have locked up in the first place?

Anyone have this issue with failed cylinder? It was brand new from AHSpares (generic BRK198) 3/4" last year.
thanks,
rich

 

[British_Recovery]

The cover with the ring is not a hydraulic seal, but only a dust cover. The fluid probably leaked when the piston with the hydraulic seal went too far in the bore (allowed by slackening the shoes?). The cylinder is probably still o.k. Use a brake-clean product on the shoes and drum. It may have locked because it was over - adjusted causing some heat. Also it is easy to assemble the shoes incorrectly. The square hole for the handbrake should be opposite the solid end, so it's "head to tail". See the manual for orientation.
Good luck, Bob