At first, the plumber who owned this VW Transporter was under the impression that he had engine problems and was concerned with the power loss. He then realised that a strange odour was being emitted from the brakes. It slowly dawned on him, that the brakes were binding. Making what could be considered a silly mistake, he felt the temperature of one of the brake discs by placing his finger though the gap in the wheel.

One burnt finger later, he phoned me to ask if I could have a look at the problem for him. When he arrived, a quick attempt at driving the Transporter confirmed that the brakes were binding.

Releasing the brake pressure by loosening a bleed screw confirmed that the problem was not any individual caliper, it was a more general problem. The next test was to loosen the brake master cylinder and allow it to move away slightly from the brake servo. This allowed the brakes to free up, and confirmed the source of the problem was the brake servo unit. It was putting pressure on the master cylinder and applying the brakes just enough to give the symptoms of a binding brake.

Once the parts arrived, the job of replacing the servo was completed in under two hours.

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