Mack CHM 2010, Руководство оператора

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118 OPERATION
Automatic Slack Adjusters
Automatic slack adjusters are designed to automatically maintain proper brake chamber
pushrod travel and compensate for brake lining wear during normal use. Manual adjustment
of an automatic slack adjuster should never be performed except when performing brake
or wheel service (such as backing off the brake shoes for wheel removal, brake shoe
relining/replacement, brake drum reconditioning, etc.).
When pushrod travel exceeds specifications (as given in the "BRAKE ADJUSTMENT"
section of the
Maintenance and Lubrication Manual, ) on a vehicle equipped with automatic
slack adjusters, a mechanical problem with the slack adjuster, brake components or improper
installation of the slack adjuster is indicated. If brakes are found to be out of adjustment, the
vehicle must be taken to the nearest repair facility as soon as possible to have the problem
investigated and corrected.
DANGER
Automatic slack adjusters should not be
manually adjusted in an effort to correct
excessive pushrod stroke, because this
condition indicates that a problem exists
with the automatic adjuster, with the
installation of the adjuster, or with related
foundation brake components, which
manual adjustment will not fix. Manual
adjustment of automatic slack adjusters
is a dangerous practice that could have
serious consequences, because it gives the
operator a false sense of security about
the effectiveness of the brakes, which are
likely to go out of adjustment again soon.
Parking Brake System
Spring-type parking brakes are standard on all single and tandem rear axles.
The spring brake system consists of an air cylinder with heavy springs, which is integrated
with the spring brake air chamber. When there is no pressure in the air chamber, the springs
expand (causing a brake application). When air pressure is applied to the air chamber, the
springs are compressed (releasing the brakes).