pshnfry
Member
- Joined
- Jan 5, 2011
- Location
- South Australia
89 build 745 GLE B234F Auto.
Problem with the brakes driving the wagon yesterday, lots of heavy stop start traffic. Looking for suggestions on where to start looking - see the story below.
======================================================
Part way through the trip the brake pedal travel went long - probably twice the travel to get braking effect and seemed to be more sensitive to pressure when the brakes did bite. Definitely still getting good brakes, just really long travel.
This progressed towards the end of the trip to becoming more of a "dead" pedal with minimal stopping power .
Pumping the pedal did not correct the long travel.
Noted the pedal when released came back up 80%, paused for a second or two and then went up fully to the expected height.
Left the car parked for 3 hours, started it up and found normal brake travel and feel, drove it back home in light traffic with no issues.
This is the second time in 6 months it has done this to me. Same circumstances and outcome both times.
Last time it happened I pulled the pads in all four wheels and cleaned up the pad locating pins with a drill and emery paper. Pads still had plenty of life and wearing evenly. The front discs had passed minimum thickness and were replaced with careful pad bedding (no replacement of pads).
Master cylinder is at the correct level. Fluid is getting towards needing a flush. Car is original and has low mileage.
Brake booster has made light "groaning" noise on initial pedal travel for several years, but retains assistance for two pedal pumps after the motor stops so I'm not expecting to be looking at that.
Master cylinder may be the original 32 year old part, but the intermittent and infrequent nature of the problem doesn't gel with this failing.
=====================================================
Any thoughts or ideas on where to look first this weekend?
Problem with the brakes driving the wagon yesterday, lots of heavy stop start traffic. Looking for suggestions on where to start looking - see the story below.
======================================================
Part way through the trip the brake pedal travel went long - probably twice the travel to get braking effect and seemed to be more sensitive to pressure when the brakes did bite. Definitely still getting good brakes, just really long travel.
This progressed towards the end of the trip to becoming more of a "dead" pedal with minimal stopping power .
Pumping the pedal did not correct the long travel.
Noted the pedal when released came back up 80%, paused for a second or two and then went up fully to the expected height.
Left the car parked for 3 hours, started it up and found normal brake travel and feel, drove it back home in light traffic with no issues.
This is the second time in 6 months it has done this to me. Same circumstances and outcome both times.
Last time it happened I pulled the pads in all four wheels and cleaned up the pad locating pins with a drill and emery paper. Pads still had plenty of life and wearing evenly. The front discs had passed minimum thickness and were replaced with careful pad bedding (no replacement of pads).
Master cylinder is at the correct level. Fluid is getting towards needing a flush. Car is original and has low mileage.
Brake booster has made light "groaning" noise on initial pedal travel for several years, but retains assistance for two pedal pumps after the motor stops so I'm not expecting to be looking at that.
Master cylinder may be the original 32 year old part, but the intermittent and infrequent nature of the problem doesn't gel with this failing.
=====================================================
Any thoughts or ideas on where to look first this weekend?