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ENGINE —
—
B R
D I A G N O S I S A N D T E S T I N G (Continued)
S E R V I C E
DIAGNOSIS—DIESEL—PERFORMANCE—CONT.
CONDITION
POSSIBLE CAUSES
CORRECTION
COOLANT TEMPERATURE
ABOVE NORMAL CONT.
10. Inoperative water pump.
11. Incorrect injection pump timing.
12. Overfueied injection pump.
13. Plugged cooling passages in
radiator, head, head gasket or
block.
14. Engine overloaded.
10. Check and replace the water pump.
11. Check/time the injector pump (refer to
Group 14, Fuel System).
,
12. Repair or replace the injection pump.
13. Flush the system and fill with clean
coolant.
14. Verify that the engine load rating is nci
being exceeded.
COOLANT TEMPERATURE
BELOW NORMAL
1. Too much air flow across the
radiator.
2. Incorrect thermostat or
contamination in thermostat.
3. Temperature sensor or gauge
inoperative.
4. Coolant not flowing by
temperature sensor.
1. Check/repair viscous fan drive as
required.
2. Check and replace thermostat.
3. Verify that the gauge and sensor are
accurate. If not, replace gauge/sensor.
4. Check and clean coolant passages.
J9509-151