ENGINE MAINTENANCE PREVENTIVE MAINTENANCE
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Regional Haul (R05/10)
1. Rotate the new belt around the pulleys, and then
rotate the automatic tensioner so that the idler pulley
swings toward the belt routing. The graphic below-
shows an example of the rotation direction to release
the tensioner.
2. Slip the belt around the idler pulley attached to the
automatic tensioner.
3. Release the automatic tensioner.
4. Check the belt alignment on each pulley. The belt
must fall between the flanges of each pulley.
Engine Fan
Thermatic (Clutch) — Type Fan
WARNING! Do not work on the fan with the
engine running. The engine fan can engage at
any time without warning. Anyone near the
fan when it turns on could be killed or seri-
ously injured. Before turning on the ignition,
be sure that no one is near the fan.
To Check the Fan:
• Check the fan assembly mounting bolts for tightness.
Inspect the blades for damage.
• Check the clutch operation by starting the engine
when it is cold. Then idle it at about 800 RPM. Listen
for air leaks.
• Check that the fan is not working while the engine is
warming. When the clutch engages, note the reading
on the vehicle's panel—mounted coolant temperature
gauge. If the fan clutch engages at low engine tem-
perature or cycles on and off more frequently than it
should (receives “false signals”), have the problem
corrected at an Authorized Service Center.
