Operation and maintenance manual

QSB4.5 and QSB6.7 Troubleshooting Symptoms Charts

Section TS - Troubleshooting Symptoms Page TS-11

Coolant Contamination

Cause Correction

STEP 1

Coolant is rusty and has debris

.............

Drain and flush the cooling system. Fill with correct

mixture of antifreeze and water. Refer to Section 7.

Go To Next Step

STEP 2

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.

Go To Next Step

STEP 3

Lubricating oil cooler is leaking

.............

Check the lubricating oil cooler for coolant leaks

and cracks. Refer to a Cummins Authorized Repair

Facility.

Go To Next Step

STEP 4

Cylinder head gasket is leaking

.............

Check the cylinder head gasket. Refer to a

Cummins Authorized Repair Facility.

Go To Next Step

STEP 5

Contact a Cummins® Authorized Repair Facility