Mercedes CLK 4.3 2001 - Brakes seizing

Honest John Back Room » Technical matters
What is life like with your car? Let us know and win £500 in John Lewis vouchers | No thanks
View Threaded
Fri 23 Aug 2013 11:32
Mercedes CLK 4.3 2001 - Brakes seizing - jarm

The brake pedal seemed to stick own without warning and although I tried to lift it up the brakes had locked on. (The handbrake was definitely off!) We stopped as quickly as possible on the narrow busy road but the discs were very hot and the front offside was beginning to smoke. We were recovered to the local garage who checked the car the following morning but could find no fault. The discs, pads, calipers, linkages, brake fluid and master cylinder all seemed perfect and the garage could not reproduce the fault. Before we bought the car last year, another garage had the same problem and replaced the discs, pads, calipers, sensor wires and brake fluid. The car has covered less than 1000 miles since these renewals were done.

Has anyone else had a similar problem? And can suggest a solution? There are two garages would love to know what the problem was as they are baffled. Thanks

Reply | Report as offensive | Link
Fri 23 Aug 2013 12:33
Mercedes CLK 4.3 2001 - Brakes seizing - Peter D
The symptoms you describe are those of a faulty brake servo. Seens lots of this on Audi's due to water build up in the plenum chamber, corrosion of the servo housing seal and water ingress into the Servo unit. Fault applies enough pressure, i.e. the pedal dropping down to overheat the pads/disc's particularly the fronts. Regards Peter
Reply | Report as offensive | Link
Fri 23 Aug 2013 16:20
Mercedes CLK 4.3 2001 - Brakes seizing - jarm

Peter D

Thank you for your answer. I will pass your comments on to the mechanic and suggest he checks this out to see if I have n identical problem to the Audis you have seen.

Very helpful - many thanks. I will let you know if he confirms your diagnosis as it may help others.

Reply | Report as offensive | Link
Fri 23 Aug 2013 18:52
Mercedes CLK 4.3 2001 - Brakes seizing - Collos25

Do not rule out flexi hoses it is not usual for these to break down inside and act as oneway valve causing the brakes to stay on then release themselves over time when not in use.

Reply | Report as offensive | Link
Fri 23 Aug 2013 18:56
Mercedes CLK 4.3 2001 - Brakes seizing - Peter D
Check on the Merc Forums. I am sure you will come across cases of this. Inspection around the seal can show corrosion. The last one I dealt with did it three times and the garage was stuck for ideas but the guy who owned the car ( A Passat ) insisted they changed the servo and the fault has not returned. Must be 12/14 months now. Regards Peter
Reply | Report as offensive | Link