GM Prizm/Nova 1985-1993 Repair Guide

Brake and Clutch Master Cylinders



Both the hydraulic brake system and the hydraulic clutch system use brake fluid in the lines. Select a quality fluid meeting DOT 3 or DOT 4 specifications. DO NOT use brake fluid from previously opened containers which have been sitting around for any length of time - it will have absorbed enough moisture from the air to make it useless.


See Figures 1 and 2

The brake and clutch master cylinders are located under the hood in the left rear section of the engine compartment. They are made of translucent plastic so that the levels may be checked without removing the tops. The fluid level in both reservoirs should be checked at least every 5,000 miles. The fluid level should be maintained at the uppermost mark on the side of the reservoir. Any sudden decrease in the level indicates a possible leak in the system and should be checked out immediately.

Normal brake wear will cause the fluid level to drop over a period of time. The fluid isn't leaking - it's simply relocated within the system.

When making additions of brake or clutch fluid, use only fresh, uncontaminated brake fluid meeting or exceeding DOT 3 or 4 standards. Be careful not to spill any brake fluid on painted surfaces, as it eats paint.

Click image to see an enlarged view

Fig. Fig. 1: Always fill the master cylinder slowly so as not to create air bubbles in the system

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Fig. Fig. 2: Master cylinder reservoir location - 1992 VIN code 6 engine shown

Before removing the caps to either reservoir, wipe off the cap area with a rag. This helps prevent dirt from entering the system. Do not allow the master cylinder reservoir to remain open any longer than necessary; brake fluid absorbs moisture from the air, reducing its effectiveness and causing corrosion in the lines.