Ford Tempo/Topaz 1984-1994 Repair Guide

Brake Master Cylinder


The braking system of most vehicles is a closed system utilizing fluid pressure to drive pistons in the calipers, cylinders or both, which in turn engages the pads or shoes to slow the vehicle down. In the event there is air or a leak in the brake system, the braking pressure is reduced therefore decreasing the possible brake braking efficiency. If there is water or condensation in the brake lines or reservoir, the bake system is also adversely effected. Therefore, it is important to check and maintain your brake system.


The brake fluid to be used in these vehicles should be of a DOT 3 , or higher classification. The number associated with brake fluid corresponds to it's respective boiling point. In general, the higher the number, the higher the boiling point.


See Figure 1

The brake master cylinder is located under the hood, on the driver's side firewall. Before removing the master cylinder reservoir cap, make sure the vehicle is on a level surface. Wipe the cover and around the master cylinder clean, before removing the cap. Depending on the type of reservoir you may have to either pry the retaining clip off to the side, or turn a cap to remove the master cylinder cover.

Once the cap is removed, if the level of the brake fluid inside is within 1 / 4 in. (6mm) of the top, the fluid level is OK. If the level is less than half the volume of the reservoir, check the brake system for leaks. Leaks in the brake system most commonly occur at the wheel cylinders or at the front calipers, or a cracked rubber brake line leading to either a front or rear brake.

When checking the fluid level, make sure the rubber gasket inside the cap is in good working condition. The rubber should be soft, with no visible cracks. If there is any question, replace it. This cap not only prevents dirt from entering the reservoir, it also helps maintain system pressure when the fluid level goes down.

Never over fill a brake reservoir. The fluid will only leak out, and this can cause debris to enter the system, not to mention that brake fluid is a hazardous fluid, and can easily strip paint off a car.

On the later vehicles, check the brake fluid by visually inspecting the fluid level through the translucent master cylinder reservoir. It should be between the MIN and the MAX level marks embossed on the side of the reservoir. If the level is found to be low, remove the reservoir cap and fill to the MAX level with DOT 3 brake fluid.

The brake fluid level will decrease with accumulated mileage. This is a normal condition associated with the wear of the disc brake linings. If the fluid is excessively low, it would be advisable to have the brake system checked.

To avoid the possibility of brake failure that could result in property damage or personal injury, do not allow the master cylinder to run dry. Never reuse brake fluid that has been drained from the hydraulic system or fluid that has been allowed to stand in an open container for an extended period of time.

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Fig. Fig. 1: Brake master cylinder and reservoir