IC Bus CE Series 2020, Operation And Maintenance Manual

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Operation
Above normal coolant temperature could be temporarily
decreased by down shifting into the next lower gear.
This
increases engine rpm, which increases coolant flow and air flow
through the radiator.
NOTE: If above normal operating temperatures persist, have
vehicle serviced at first available opportunity.
Turning OFF the Engine
Allow the engine to idle for 3-5 minutes before shutting it down.
This allows the lubricating oil and coolant to carry heat away
from the large iron components and the turbocharger, preventing
engine damage from rising heat.
Brakes
Downhill Operation
Always descend hills with extreme care. Heed warning signs
posted for any grade. Stop and check brakes for condition and
adjustment at available pull off areas before starting a descent.
Observe the following precautions:
• Never coast downhill. Service brakes alone should not
be used to control speed on major downgrades. Brakes
fade from overuse.
• The downhill speed is controlled by removing your foot
from the accelerator pedal and putting the transmission
in a reduced gear. If the gear selection does not hold the
desired speed without overuse of the brakes, an improper
gear selection was made.
• Make a full stop. Let the brakes cool, then continue down
the grade in a lower gear range.
• The common rule to follow in using the engine and
transmission to control vehicle speed is to select the
same gear going down the hill that would be required to
ascend the hill.
• The service brakes should be used to supplement
available vehicle retardation.
When descending long
grades requiring use of the brakes, short applications
(five to ten seconds duration) should be made rather than
long, lighter, continuous applications.
This minimizes
temperature brake fade.
Warning Indicators
Instrument Panel Gauge Cluster indicators identify brake
system fault conditions. Certain faults may also result in cluster
alarms. The following lists some of the common faults (See
fault indicators in Instrumentation section):
NOTE: Whenever a brake system warning indicator is lit, do
not operate the vehicle until the faulty condition has been
corrected.
• Brake Pressure. ON STEADY when either front or rear
brake system brake pressure failure is detected. ON
STEADY when the system is in backup mode where
primary boost is lost (no power steering flow when the
engine is OFF).
• Brake Fluid. ON steady when low fluid level is detected
in master cylinder reservoir.
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