2.4
When proper adjustment is obtained,
tighten the adjusting screw locknut, and
install the top cover. The pressure range
between cut-in and cut-out is not adjust-
able.
Cut-In Position
Apply soap solution around the cover and to the ex-
haust port. Slight bubble leakage is permitted. Exces-
sive leakage indicates a faulty inlet valve or faulty
lower piston O-ring.
Cut-Out Position
Apply soap solution around the cover and to the ex-
haust port. Slight bubble leakage is permitted. Exces-
sive leakage indicates a faulty exhaust valve seat,
exhaust stem O-ring, or O-ring at the top of the
piston.
If the governor does not function as described, or if
leakage is excessive, it is recommended that it be
replaced with a new or remanufactured unit, or re-
paired with genuine Bendix parts.
42–04 Bosch Hydraulic Brake
System Inspection
Before checking lining wear with the wheel removed,
review the following brake lining exposure warnings.
WARNING
Breathing brake lining dust (asbestos or non-
asbestos) could cause lung cancer or lung dis-
ease. Unless exposure can be reduced below legal
limits, wear an air purifying respirator approved
by MSHA or NIOSH at all times when servicing the
brakes, starting with removal of the wheels and
continuing through assembly.
To minimize the possibility of creating airborne brake
lining dust, clean the dust from the brake rotor, brake
caliper, and brake assembly, using an industrial-type
vacuum cleaner equipped with a high-efficiency filter
system. Then, using a rag soaked in water and
wrung until nearly dry, remove any remaining dust.
Do not use compressed air or dry brushing to clean
the brake assembly.
1.
Check lining wear, as follows.
1.1
Apply the parking brakes. Chock the tires
to prevent vehicle movement.
1.2
Remove one or more of the lining inspec-
tion plugs, and measure brake lining
thickness.
1.3
On front and rear axles, replace linings
worn to less than 1/16 inch (1.6 mm).
1.4
Make sure that the brake rotor and linings
are free of oil and grease.
1.5
Install the inspection plug(s).
2.
If the wheel and hub assembly is removed from
the axle, check lining wear. Replace the linings
on all brake assemblies if worn to less than 1/16
inch (1.6 mm) at the thinnest point. Check the
brake pads for wear and replace, as necessary.
42–05 Dana Spicer, Haldex,
and Gunite Slack
Adjuster Lubrication
IMPORTANT: Perform a brake inspection before
lubricating the camshaft bracket.
Automatic slack adjusters that have a grease fitting
must be lubricated periodically to ensure proper
brake operation.
WARNING
Failure to lubricate slack adjusters could lead to
dragging brakes or a brake failure, resulting in
property damage, personal injury, or death.
Dana Spicer and Haldex
WARNING
Do not use moly-disulfide-loaded grease or oil.
Both the life and reliability of the slack adjuster
will be reduced if this type of grease is used,
which could lead to brake failure, resulting in
property damage, personal injury, or death.
Lubricate the automatic slack adjuster at the grease
fitting. See
for a Dana Spicer slack adjuster.
Dana Spicer Low Lube slack adjusters should be lu-
bricated with SHC 460 synthetic lubricant. See
Brakes
42
Business Class M2 Maintenance Manual, November 2015
42/5
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