BMW Coupes and Sedans 1970-1988 Repair Guide

Clutch and Brake Master Cylinder



Use only high quality, name brand DOT 4 brake fluid. Use tightly sealed small containers to refill the reservoir. Large containers offer a false economy. A large container that has been opened will absorb moisture and ruin the fluid. Only use large containers when performing major work on the brake or clutch hydraulic systems and the entire contents will be used at once.

Tightly cap any container to prevent moisture from being absorbed into the brake fluid.


See Figures 1, 2, 3 and 4

On all but the 1600 models, the fluid reservoir services both he brake and clutch master cylinder. On the 1600, no fluid is involved in clutch operation. The fluid level should be checked at every oil change.

Wipe the reservoir cap and surrounding area clean. Make sure the level is up to the full marker located on the side of the reservoir. If necessary, add DOT 4 specification fluid that is brand new. Never attempt to reuse brake fluid). Be careful not to drop any dirt into the fluid, and avoid spilling fluid on the paint work, or wipe it up immediately if it spills. Make sure the vent hole used in earlier type reservoirs is clean. If it is not clean, blow air through the hole.

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Fig. Fig. 1: The 2002 brake fluid reservoir

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Fig. Fig. 2: Brake fluid reservoir. Notice the MAX and MIN marks

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Fig. Fig. 3: Clean around the fill cap with a rag, then unscrew it

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Fig. Fig. 4: Add DOT 3 or DOT 4 brake fluid to just below the MAX line