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I had brake failure on my worn out `99 Ford Ranger. Two days ago was driving and the pedal felt spongy. It would slowly go down and if I let off pressure slightly seemed to go farther down each time. My initial diagnosis was the master cylinder was bypassing or leaking out the back. Didnt bother to check anything tho.
Yesterday I was headed out and noticed the ABS and brake lights were both on now. But one big difference from the day before. Pedal was gone and went right to the floor. I finished my local run and headed back to shop. It is a stick shift, so without brakes isnt too hard to drive. Of all the years driving old worn out forklifts, brakes were an unexpected luxury. So reliving my earlier years of living on the edge.
Today, I decided to check the brakes out. First thing obvious is master cylinder is empty. But nothing leaking down the brake booster. So there had to be a leak somewhere. I looked under the bed at both wheels. Left side was soaked with brake fluid.
Pulled the wheel and drum. Wheel cylinder is dripping and everything is soaked with fluid. Odd the wheel cylinder just decides to take a dump. Even tho the truck has 170,000+ miles and now over 20 years old. It also has never had the rear brakes replaced, no reason for the wheel cylinder to suddenly die like this.
After removing the wheel cylinder I tore it apart and found one of the cups to be deformed and severely worn. Not anything I am accustomed to or expecting to see. Normally on higher mileage vehicles, the cups will be leaking, but not too bad. This went from working fine then emptied master cylinder and nothing.
Left one is normally what I would expect to see. Working fine if bore of cylinder is not rusted, have buildup, or pitted.
The base diameter of cup is rounded over and worn down considerably. There was not any real buildup in cylinder bore. I wold normally dig thru my stockpile and replace just the cups, if honing cleans bore well enough.
Instead I gave in and bought a new wheel cylinder locally. Washed the shoes and cleaned the hardware in MEK. Put everything went back together and just cracked the bleed screw. Then lightly pumped the pedal until it quit spitting out air. Now the pedal is back up solid and good as new again.
I am still trying to figure out why the cup was worn this way. I have seen a lot of odd things from worn brakes. Even tho this isnt any real travesty, I still would like to understand why the one cup died.
Yesterday I was headed out and noticed the ABS and brake lights were both on now. But one big difference from the day before. Pedal was gone and went right to the floor. I finished my local run and headed back to shop. It is a stick shift, so without brakes isnt too hard to drive. Of all the years driving old worn out forklifts, brakes were an unexpected luxury. So reliving my earlier years of living on the edge.
Today, I decided to check the brakes out. First thing obvious is master cylinder is empty. But nothing leaking down the brake booster. So there had to be a leak somewhere. I looked under the bed at both wheels. Left side was soaked with brake fluid.
Pulled the wheel and drum. Wheel cylinder is dripping and everything is soaked with fluid. Odd the wheel cylinder just decides to take a dump. Even tho the truck has 170,000+ miles and now over 20 years old. It also has never had the rear brakes replaced, no reason for the wheel cylinder to suddenly die like this.
After removing the wheel cylinder I tore it apart and found one of the cups to be deformed and severely worn. Not anything I am accustomed to or expecting to see. Normally on higher mileage vehicles, the cups will be leaking, but not too bad. This went from working fine then emptied master cylinder and nothing.
Left one is normally what I would expect to see. Working fine if bore of cylinder is not rusted, have buildup, or pitted.
The base diameter of cup is rounded over and worn down considerably. There was not any real buildup in cylinder bore. I wold normally dig thru my stockpile and replace just the cups, if honing cleans bore well enough.
Instead I gave in and bought a new wheel cylinder locally. Washed the shoes and cleaned the hardware in MEK. Put everything went back together and just cracked the bleed screw. Then lightly pumped the pedal until it quit spitting out air. Now the pedal is back up solid and good as new again.
I am still trying to figure out why the cup was worn this way. I have seen a lot of odd things from worn brakes. Even tho this isnt any real travesty, I still would like to understand why the one cup died.
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