Operation and maintenance manual

QSB4.5 and QSB6.7 Troubleshooting Symptoms Charts
Section TS - Troubleshooting Symptoms Page TS-13
Coolant Temperature Above Normal - Gradual Overheat
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
Coolant level is below specification
.............
Inspect the engine and cooling system for external
coolant leaks. Repair if necessary. Add coolant.
Refer to Section 7.
OK
Go To Next Step
STEP 4
Electronic fault codes are active
.............
For instructions on how to read active fault codes,
refer to Section 1. If fault codes are active, contact
a Cummins Authorized Repair Facility.
OK
Go To Next Step
STEP 5
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 6
Lubricating oil is contaminated with coolant or fuel
.............
Refer to the Lubricating Oil Contaminated
symptom tree.
OK
Go To Next Step
STEP 7
Cooling system hose is collapsed, restricted, or
leaking
............. Inspect the hoses. Refer to Section 4.
OK
Go To Next Step
STEP 8
Coolant mixture of antifreeze and water is not
correct
.............
Verify the concentration of antifreeze in the
coolant. Add antifreeze or water to correct the
concentration. Refer to Section 5 and Section V.
OK
Go To Next Step
STEP 9
Lubricating oil level is above or below specification
.............
Check the oil level. Add or drain oil, if necessary.
Refer to Section 3. Use the oil recommended in
Section V.
OK
Go To Next Step