I just bought an '87 190D and am trying to fix a problem with the brakes. The rear brakes (drivers side in particular) are staying engaged at all times. I thought that this was likely a problem with the emergency brake because of the fact that it was only the rear but after getting underneath and looking at it, I'm not so sure. The line for the emergency brake goes into the hub opposite the calipers and the hydraulic brake line which leads me to believe that it is not connected to the main brakes. Can somebody tell me if the emergency brakes operate through the same calipers as the hydraulic brakes? This is my first shot at working on them (obviously) so any insight would be greatly appreciated!

The parking brake is a seperate system that operates on drums inside of the rear disks. Sound like you possibly have a sticking caliper.

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Ali Al-Chalabi

2001 CLK55
1999 Dodge Ram 2500 Cummins Diesel
2002 Harley-Davidson Fatboy
Merlin Extralight w/ Campy Record

'original brake (rubber hoses at the wheels) lines???
It is possible for a collapsing hose to hang up the caliper

Your Parking/Emergency brakes have an adjustment to the cable(s) underneath the body.

Yes.. the brakes appear to be original. Now that I know the emergency brake operates separately, it must be a problem with the hydraulic brakes. Both sides are rubbing, however, one is much worse and has been worn all the way down and grooved the rotor. Has anyone had a similar problem or have any suggestions on what the cause might be??

1.Brake fluid is hydroscopic(it sucks moisture out of the air).The brake system
must vent to the outside air as designed,to allow the fluid to move the pads
towards the rotors.
2.Old brake fluid (black or dark brown in color)is acidic(not good).M.B. requires
fluid replacement every two years(Cheap way to assure you stop when the
pedal is depressed)
3.Old brake hoses tend to collapse and not allow the pads to fully retract from
the rotors.
4.Brake dust loves to glom onto everything it comes into contact with...say the
interface between the pads and the caliper(and caliper bolts)...possibly further
compounding the sticking problem.
5.#3and #4 can cause sticking calipre(s).
6.Very worn pads can allow the piston(s) in the caliper to overextend and
stick.

At the very least you need to see if the rotors have enough meat left to
have them "Turned"(Shaved down to a flat surface)otherwise the damage
to the rotors will kill a new set of pads.You'll get to replace the shoes inside
the parking brake drums(you should turn the inside of the drums if any
damage shows)Press the pistons back into the calipers per the manual...
if they are damaged or the seals or bores are damaged rebuild or replace.
Replace the brake fluid...I'd replace the brake hoses too , they are inexpensive.