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General Maintenance
The drum brakes on all modern cars are equipped with automatic brake adjusters that maintain proper pedal height as the brakes wear. On most cars, these adjusters are activated when you put on the brakes while the car is moving backwards. So, if you have to push your brake pedal down more than a couple of inches before the brakes begin to take hold, find a safe area away from traffic and apply the brakes firmly several times while moving in reverse. If this fails to bring the pedal up to an acceptable height, remove the brake drums and inspect the adjusters to see if they are jammed or rusted.
Disc brakes are designed so they do not require periodic adjustment. As the linings slowly wear out and the brake pedal is applied, the piston in the caliper slowly moves out toward the rotor to compensate for brake pad wear. The area displaced directly behind the piston is slowly occupied by the brake fluid. For this reason, disc brakes require a greater amount of brake fluid.
You should adjust the parking brake when you have to move the foot pedal or handle a greater distance than usual to apply the brake.
Linings
At least once a year, more often if you do a lot of driving, or drive constantly in heavy stop-and-go city traffic, remove, or have your mechanic remove, the brake drums and inspect the linings. If they are permitted to wear excessively, the metal rivets securing the lining to the shoe, or the steel locking of the brake shoe itself, may grind grooves in the drum's braking surface. In such cases, the drum will have to be resurfaced or, if beyond specified tolerances, replaced.
Remove one of the front wheels and inspect the brake disc, caliper, and linings. See the detailed procedures provided later in this chapter, presented by make and model.
Do not get any oil or grease on the linings. If the pads are worn to within .030-inch of the surface of the steel shoe, replace both the front and/or rear sets of shoe and lining pad assemblies.
If the caliper is cracked or fluid leakage through the casting is evident, it must be replaced as a unit. While you have the wheel off to inspect the linings and pads, inspect all hydraulic brake lines. Look for leaks, cracks, lines that have become thin by rubbing against a suspension part, and any other signs of wear or deterioration. Caution: Do not attempt to disconnect any hydraulic lines yourself. Take your car to a professional mechanic for this job. He is qualified to do it safely and correctly.
As the linings eventually wear out and have to be replaced, remember that the rest of the brake system components have been in service just as long as the linings. At this time, it is very important to check the master cylinder, the wheel cylinders, the drums, and the shoe retaining and retracting springs. If these parts are not checked at this time, more than likely they will not be checked until the next overhaul, or until the brakes finally fail;when it will be too late.
Replacing the master cylinder, the wheel cylinders, and the internal components of drum brakes is best left to a professional mechanic. Repair and replacement procedures you can tackle are described on the following pages.
At the same time the brakes are relined, clean, inspect, and repack the wheel bearings with the proper lubricant. Adjust the wheel bearings to the manufacturer's specifications to prevent wheel wobble and unbalanced braking action. To be on the safe side, install new seals to prevent the wheel bearing grease from contaminating the new brake shoes.
Fluid level
Every time you change your engine oil, check the level of the brake fluid in the master cylinder. Checking the level is easy. Locate the master cylinder under the hood, then simply unlatch the cylinder cover, remove the top, and look at the fluid level. If it is low (more than 1/4-inch below the top edge of the reservoir), add only the approved type heavy-duty brake fluid. Also, check for leaks around the hoses, lines, and at the wheels. If brake fluid has contaminated the linings, they must be replaced.
General hints
Before you begin work, jack up the car and support it on safety stands. Use fender covers to protect your car's body paint from damage caused by brake fluid. Be sure to wipe up any spilled fluid.
To prevent excess spillage, begin by removing at least two-thirds of the brake fluid from the larger compartment of the master cylinder. Use an ordinary kitchen baster with a tube and suction bulb. Discard the fluid. Do not reuse it.
To complete the job, after both front wheels have been serviced:
1. Fill the master cylinder and re-place its cover. Caution: Never pump the brake pedal with the cover of the master cylinder off. Fluid may squirt out of the cylinder and damage parts in the engine compartment or the body finish.
2. If you have power brakes, start the engine.
3. Pump the brakes. They should feel hard and high. If not, recheck your work.
4. Turn off the engine.
5. Check for leaks.
6. Be sure the master cylinder fluid level is correct.
7. Lower the car.
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