1. Inspect for cracks in the master cylinder body.
2. Inspect for brake fluid around the master cylinder.

•	A leak exists if there is at least one drop of fluid.

•	A damp condition is not abnormal.

3. Inspect for binding brake pedal linkage.
4. If the pedal linkage is correct, remove the master cylinder reservoir cap. Inspect for the following conditions:

•	A distorted or swollen master cylinder reservoir diaphragm

•	Swollen primary or secondary piston seal(s)

5. If a swollen diaphragm or secondary piston seal(s) are found, substandard or contaminated brake fluid is the probable cause. If the fluid is contaminated, use the following procedure:

5.1.	Disassemble and clean the serviceable components.

5.2.	Replace all of the non-serviceable rubber components.

5.3.	Flush all of the brake pipes and the hoses.

In order to diagnose malfunctions in the master cylinder, refer to Brake System Diagnosis .