Symptom Tree t021
Cause | Correction |
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Excessive internal or external engine coolant loss |
Before troubleshooting, it is important to determine the exact complaint by interviewing the driver, looking at the service history, and looking at the ECM information. Refer to the Coolant Loss Pre-Troubleshooting Guide at the end of Section TS. |
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Radiator cap is not correct, is malfunctioning, or has low-pressure rating |
Check the radiator pressure cap. Refer to Procedure 008-047 in Section 8. |
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Pressure test the cooling system |
After verifying the above step, to pressure test the cooling system, refer to Procedure 008-018 in Section 8. If this step was completed for the same complaint within the last 30 days (as per history), skip to the next step. |
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Air compressor cylinder head is cracked or porous, or has a leaking gasket |
Inspect the air compressor air inlet and outlet tubes for signs of coolant. Refer to Procedure 012-007 in Section 12. |
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Air compressor cylinder head is cracked or porous, or has a leaking gasket |
Inspect the air compressor cylinder head and gasket. Refer to the Master Repair Manual, Holset® Air Compressors, Bulletin 3666121 and the Cummins® Single Cylinder Air Compressor Service and Maintenance Procedures, Bulletin 3666476. |
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Turbocharger leaking coolant |
Refer to |
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Aftertreatment fuel injector is leaking coolant |
Check the aftertreatment fuel injector for coolant leaks. Refer to |
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Lubricating oil cooler is leaking |
Check the lubricating oil cooler for coolant leaks. Refer to Procedure 007-003 in Section 7. |
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Air or combustion gases are entering the cooling system |
Check for air or combustion gases in the cooling system. Refer to Procedure 008-019 in Section 8. |
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EGR cooler leaking coolant |
Check the EGR cooler for leaks. Refer to Procedure 011-019 in Section 11. |
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Cylinder head gasket is leaking |
Check the cylinder head gasket. Refer to Procedure 002-004 n Section 2. |
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Cylinder head is cracked or porous, or an injector sleeve is leaking |
Pressure test the cylinder head and inspect the injector sleeves. Refer to Procedure 002-004 in Section 2. |
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Fuel heater is malfunctioning (if equipped) |
Check the fuel heater and replace, if necessary. Refer to the OEM service manual. |
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Transmission oil cooler or torque converter cooler is leaking |
Check the transmission oil cooler and torque converter cooler for coolant leaks. Refer to the OEM service manual. |
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Cylinder liner is corroded or cracked, or the cylinder block is cracked or porous |
Remove the oil pan. Pressure test the cooling system to check for leaks. Refer to Procedure 001-027 in Section 1. |