Operation and maintenance manual

Troubleshooting Symptoms Charts QSB4.5 and QSB6.7
Page TS-50 Section TS - Troubleshooting Symptoms
Intake Manifold Air Temperature Above Specification
Cause Correction
STEP 1
Charge air cooler fins, radiator fins, or air
conditioner condenser fins are damaged or
obstructed with debris
.............
Inspect the charge air cooler, air conditioner
condenser, and radiator fins. Clean, if necessary.
Refer to Section 4 and the OEM service manual.
OK
Go To Next Step
STEP 2
Cold weather radiator cover or winterfront is closed
.............
Open the cold weather radiator cover or the
winterfront. Maintain a minimum of 387 cm
2
[60
in
2
] of opening at all times. Refer to Section 1.
OK
Go To Next Step
STEP 3
Fan drive belt or water pump belt is broken
.............
Check the fan drive belt and water pump belt.
Replace the belts if necessary. Refer to Section A.
OK
Go To Next Step
STEP 4
Fan shroud is damaged or missing or the air
recirculation baffles are damaged or missing
.............
Inspect the shroud and the recirculation baffles.
Repair, replace, or install, if necessary. Refer to
the OEM service manual.
OK
Go To Next Step
STEP 5
Radiator shutters are not opening completely or
the shutterstat setting is wrong
.............
Inspect the radiator shutters. Repair or replace if
necessary. Refer to the manufacturer's
instructions. Check the shutterstat setting. Refer to
the OEM service manual.
OK
Go To Next Step
STEP 6
Vehicle speed is too low for adequate cooling with
high engine load
.............
Reduce the engine load. Increase the engine (fan)
rpm by downshifting.
OK
Go To Next Step
STEP 7
Vehicle cooling system is not adequate
.............
Verify that the engine and vehicle cooling systems
are using the correct components. Refer to the
OEM vehicle specifications.
OK
Go To Next Step
STEP 8
Intake manifold temperature gauge is
malfunctioning, if equipped
.............
Test the temperature gauge. Refer to the OEM
service manual.
OK
Go To Next Step
STEP 9
Fan is not an adequate size for the application
.............
Verify that the fan is the correct size. Refer to the
engine and OEM vehicle specifications.
OK
Go To Next Step