Paccar PX-9 Operator's Manual - page 47
OPERATING INSTRUCTIONS
Continuous operation with engine
coolant temperature above or below
the engine coolant temperature
specifications listed in “Cooling
System” on page 5-15 can damage
the engine.
Engine Shutdown
Before Stopping the Engine
NOTE
DO NOT shut off the engine im-
mediately. A hot engine stores a
great amount of heat and it does
not cool down immediately after it
is shut off. Always cool the engine
down before shutting it off. You will
greatly increase its service life.
Idle the engine at 1,000 RPM for four
minutes. Then low idle for 30 seconds
before shutdown. This will allow
circulating coolant and lubricating oil
to carry heat away from the cylinder
head, valves, pistons, cylinder liners,
turbocharger, and bearings. This way
you can prevent engine damage that
may result from uneven cooling.
NOTE
For engines equipped with an elec-
tronic control module (ECM) en-
sure the key switch is turned OFF
for a minimum of 70 seconds prior
to disconnecting the continuous
(unswitched) battery power supply.
If the unswitched battery power
supply is disconnected in less than
70 seconds after the key switch
is turned OFF, active fault codes
and incorrect ECM information can
occur.
Turn the ignition switch to the OFF
position. If the engine does not
shut down, refer to “Troubleshooting
Symptom” (Section TS) in the
appropriate maintenance manual.
(12/2014)
Y53-1185-1B1
4-11
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