Rear brake caliper question

[micbrody]

I went to adjust emergency brake. I first bled both rear brakes (I had not done since getting car in November). I then followed emergency brake adjustment procedure: loosened nut on cable; stepped on brake petals a bunch of times; then adjusted nut to engage brake with 2-3 clicks. Right caliper clamps down on rotor; left seems to do nothing. (No brake compensator on this car). The left rear caliper works great with pedal; but mechanical linkage does nothing. I do see it move the arm on back of caliper. Upon closer screwing around, I could get mechanical mechanism to clamp on rotor, but only when manipulate arm to its most full range of motion, with extra pull when it reaches the end of range of motion.
I looked at the schematics of rear caliper; not sure what to do. Do I need to rebuild ?

[DieselSpider]

First check that the pads are not worn out and second from lack of use or lack of bleeding the brake system every two years the self adjuster may be so gummed up that it is not be spinning out inside the caliper.

Each brake piston on the rear wheels screws onto the parking brake actuator and there is a spring clutch inside the brake piston that automatically adjusts the free play inside the caliper however a little water and some brake fluid turned acidic is all it takes to rust and gum up the steel ball bearings in the self adjuster.

You may be able to get by with removing the caliper without disconnecting the brake lines and using a medium flat file screwing the brake piston in and then back out the same number of turns each way a few times to loosen things up however it may be time to replace or rebuild the caliper ensuring that you soak the pistons in rust remover and clean out the adjuster inside it. Note that the ball bearings behind the adjuster are in an open cage and will fall out if you remove the clip and take it apart so I use a small oven pan lined with a paper towel when I do this so they don't get away from me.

[blazingspider]

Make sure the cable for the e-brake is routed properly and moves freely within the sheath. Lots of times the cable sheath melts on the passenger side by the exhaust pipe, then the cable rusts to the wound metal underneath the sheath and you end up only operating the driver's side rear caliper when applying the e-brake.

[jdeight]

@micbrody: how did you resolve your issue? i'm having same problem. thanks.

[micbrody]

I had to rebuild caliper. When I disassembled, it turns out that previous rebuild had taken place incorrectly. The spring washers were installed INSIDE of piston; it made them useless.
I assembled with spring washers on outside of caliper , in between where lever and wedge / and body of caliper

[Frog2Spider]

I purchased 2 newly rebuilt rear calipers from one of our venders. While the hydrolics on both worked, the mechanical emergency only worked on one, The level moved, when the cable was pulled, but the internal mechanism of the caliper did not engage the cylinder to squeeze the pads.

Not very pleased with the venders solution, but it did get replaced with one that worked, only costing me an addition $100 + time and a lot of inconvenience. That vender has been moved from my 'go to' supplier to my 'use if necessary' supplier.

Dave.