NOTE: If it is difficult to distinguish the location
of a supposed bearing noise, obtain a stetho-
scope and place it on the component being
checked, not the pulley, to isolate the area from
outside interference.
8.
Inspect all pulleys for foreign objects, oil, or
grease in the grooves.
Belt Tension Inspection
Spring-Tension Type
On belts equipped with a spring tensioner, the belt
tension is automatically adjusted. Check that the ten-
sioner is holding tension on the belt by inserting the
end of a breaker bar in the 1/2-inch square hole on
the forward face of the tensioner, and rotating the
tensioner down, away from the belt. When the
breaker bar is slowly released, the tensioner should
return to its original position.
01–03 Pacbrake Inspecting and
Maintenance
With frequent use, the Pacbrake Exhaust Brake will
operate free of maintenance. However, if the vehicle
is used inconsistently, seasonally, or is exposed to
excess moisture, it will be necessary to perform pre-
ventative maintenance using the following steps:
1.
With the engine turned off, use Pacbrake Syn-
thetic Lube or Synco Super Lube and spray or
coat a sufficient amount on the restricter air cylin-
der valve shaft and the attaching locations at
each end of the actuation cylinder. See
for
the exhaust brake lubrication points.
2.
Using your hands or a pair of pliers, slide the
valve several times to distribute the lubricant
down the shaft and the attaching locations.
f150010a
A
B
C
D
E
F
11/21/94
A. Glazing
B. Separating Layers
C. Streaked Sidewalls
D. Tensile Break
E. Uneven Ribs
F.
Cracks
Fig. 2, Drive Belt Replacement Conditions
Engine
01
School Bus Chassis Maintenance Manual, June 2003
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