The use of many clips and springs makes overhaul
of the brake drum assembly very time-consuming.
Because of the enclosed drum. asbestos dust is
collected in the brake cavity and certain parts of the
to become airborne. Always wear personal
protection equipment. Dispose of waste
material and cleaning rags as hazardous waste.
For more information. see OPNAVINST
4110.2, Hazardous Material Control and
assembly can cause small particles of asbestos
Asbestos can cause cancer. Grinding
brake lining and cleaning of the brake
With the demands for increased safety in the
operation of automotive vehicles, many are now
equipped with disc brakes. The major advantage of the
disc brake is a great reduction in brake fade and the
Figure 7-15.Brake drum configurations.
consequent marked reduction in the distance required
to stop the vehicle.
Braking with disc brakes is accomplished by
forcing friction pads against both sides of a rotating
metal disc, or rotor. The rotor turns with the wheel of
the vehicle and is straddled by the caliper assembly.
When the brake pedal is depressed, hydraulic fluid
forcesthe pistonsand friction linings (pads) against the
machined surfaces of the rotor. The pinching action of
the pads quickly creates friction and heat to slow down
or stop the vehicle.
Disc brakes do not have servo or self-energizing
action. Therefore, the applying force on the brake
pedal must be very great in order to obtain a brake force
comparable to that obtained with the conventional
drum brake. Consequently, disc brakes are provided
with a power or booster unit and a conventional master
In many installations, disc brakes are used only on
the front wheels and drum brakes are continued on the
rear. However, you may on occasion find disc brakes
used on all four wheels.