Operation and maintenance manual

QSB4.5 and QSB6.7 Troubleshooting Symptoms Charts
Section TS - Troubleshooting Symptoms Page TS-53
Lubricating Oil Consumption Excessive
Cause Correction
STEP 1
Crankcase ventilation system is plugged
.............
Check and clean the crankcase breather and vent
tube. Refer to Section 3.
OK
Go To Next Step
STEP 2
Lubricating oil does not meet specifications for
operating conditions
.............
Change the oil and filters. Refer to Section 5. Use
the oil recommended in Section V.
OK
Go To Next Step
STEP 3
Lubricating oil drain interval is excessive
.............
Verify the correct lubricating oil drain interval.
Refer to Section 2.
OK
Go To Next Step
STEP 4
Lubricating oil leak (external)
.............
Inspect the engine for external oil leaks. Tighten
the capscrews, pipe plugs, and fittings. Replace
gaskets, if necessary. Refer to Section V for
specifications.
OK
Go To Next Step
STEP 5
Verify the oil consumption rate
.............
Check the amount of oil added versus the hours of
operation.
OK
Go To Next Step
STEP 6
Air compressor is pumping lubricating oil into the
air system
.............
Check the air lines for carbon buildup and
lubricating oil. Refer to a Cummins Authorized
Repair Facility.
OK
Go To Next Step
STEP 7
Contact a Cummins® Authorized Repair Facility