ISC, ISCe, QSC8.3, ISL, ISLe3, ISLe4 and QSL9 Engines – Lubricating Oil Pressure Low

Electronic fault codes active or high counts of inactive fault codes

Read the fault codes with an electronic service tool. Refer to Section TF in Troubleshooting and Repair Manual, ISB, QSB4.5, QSB5.9, QSB6.7, ISC, QSC8.3, ISL and QSL9 Engines, CM850 Electronic Control System, Bulletin 4021416, or Section TF in Troubleshooting and Repair Manual, Electronic Control System, ISC, QSC8.3 and ISL Engines, Bulletin 3666271.

Lubricating oil pressure switch, gauge, or sensor is malfunctioning or is not in the correct location

Check the oil pressure switch, gauge, or sensor for correct operation and location. Refer to the OEM service manual.

Lubricating oil level is above or below specification

Check the oil level. Add or drain oil, if necessary. Refer to
Procedure 007-009 in Section 7 and Procedure 007-037 in Section 7.

Lubricating oil leak (external)

Inspect the engine for external oil leaks. Tighten the capscrews, pipe plugs, and fittings. Replace gaskets, if necessary. Refer to
Procedure 007-001 in Section 7,
Procedure 007-003 in Section 7, Procedure 007-013 in Section 7,
Procedure 007-025 in Section 7, and Procedure 007-037 in Section 7.

Lubricating oil filter is plugged

Measure the differential pressure drop across the lubricating oil filter. Refer to Procedure 007-013 in Section 7.

Lubricating oil does not meet specifications for operating conditions

Change the oil and filters. Refer to
Procedure 007-013 in Section 7 and Procedure 007-037 in Section 7. Use the oil type recommended in Section V of the operation and maintenance manual.

Lubricating oil filter is not correct

Make sure the correct oil filter is being used. Refer to the Operation and Maintenance Manual, ISC and ISL Series Engines, Bulletin 4021428, or Operation and Maintenance Manual, QSC8.3 and QSL9 Engines, Bulletin 4021518.

Lubricating oil is contaminated with coolant or fuel

Refer to the Lubricating Oil Contaminated symptom tree.

Engine angularity during operation exceeds specification

Refer to the engine performance curves and data sheet.

Lubricating oil pressure sensor or circuit is malfunctioning (electronic controlled fuel system)

Check the lubricating oil pressure sensor and circuit. Refer to
Procedure 019-066 in Section 19 in Troubleshooting and Repair Manual, ISB, QSB4.5, QSB5.9, QSB6.7, ISC, QSC8.3, ISL and QSL9 Engines, CM850 Electronic Control System, Bulletin 4021416, or Procedure 019-066 in Section 19 in Troubleshooting and Repair Manual, Electronic Control System, ISC, QSC8.3 and ISL Engines, Bulletin 3666271.

Lubricating oil filter plumbing not routed correctly

Verify the routing of the lubricating filter plumbing is correct. Refer to
Procedure 007-092 in Section 7.

Main oil pressure regulator is malfunctioning

Check the main oil pressure regulator assembly. Refer to
Procedure 007-029 in Section 7.

Lubricating oil suction or transfer tube is loose or broken, or the gasket or o-rings are leaking

Remove and inspect the oil pan or suction tube. Refer to
Procedure 007-025 in Section 7.

Lubricating oil pump is malfunctioning

Inspect the lubricating oil pump. Refer to
Procedure 007-031 in Section 7.

Lubricating oil cooler is plugged

Check the oil cooler. Refer to
Procedure 007-003 in Section 7.

Piston cooling nozzles are damaged or are not installed correctly

Check the piston cooling nozzles for damage and correct installation. Refer to
Procedure 001-046 in Section 1.

Internal engine damage or internal lubricating oil leak

Analyze the lubricating oil. Inspect the oil filter. Check the main bearings, rod bearings, camshaft bushings, and rocker lever bushings for excessive wear. Refer to
Procedure 001-005 in Section 1,
Procedure 001-006 in Section 1,
Procedure 001-010 in Section 1, and Procedure 007-083 in Section 7.

Instant loss of lubricating engine oil

Inspect the connecting rod bearings, main bearings, turbocharger, lubricating oil pump, and lubricating oil cooler. Refer to
Procedure 001-005 in Section 1,
Procedure 001-006 in Section 1,
Procedure 007-003 in Section 7,
Procedure 007-031 in Section 7,
Procedure 010-033 in Section 10,
Procedure 010-050 in Section 10, and Procedure 010-113 in Section 10.

Significant connecting rod and main bearing damage as a result of instant loss of lubricating engine oil

Inspect the air compressor bushings, camshaft bushings, connecting rods, crankshaft, pistons and cylinder liners. Refer to
Procedure 001-010 in Section 1,
Procedure 001-014 in Section 1,
Procedure 001-016 in Section 1,
Procedure 001-028 in Section 1,
Procedure 001-043 in Section 1, and Procedure 012-014 in Section 12.