Engine Oil Leaks

Engine

Engine Oil Leaks

NOTICE: If a test drive is done, the fan air or road air blast may cause erroneous readings.

NOTE: When diagnosing engine oil leaks, the source and location of the leak must be positively identified prior to repair.

Prior to carrying out this procedure, clean the cylinder block, cylinder heads, valve covers and oil pan with a suitable solvent to remove all traces of oil.

Engine Oil Leaks - Fluorescent Oil Additive Method

Use the 12 Volt Master UV Diagnostic Inspection Kit to carry out the following procedure for oil leak diagnosis.

1. Add 29.6 ml (1 oz) of diesel engine oil dye to a minimum of 0.47L (1/2 qt) and a maximum of 0.95L (1 qt) engine oil and fill through the engine oil fill. If the oil is not premixed, the diesel engine oil dye will not have enough time to reach the crankcase, oil galleries and seal surfaces during this particular 15 minute test. The diesel engine oil dye must be mixed with oil and added through the oil fill. Check the level on the oil level indicator to determine what amount of oil to premix. If it is in the middle of the crosshatch area or below the full mark, use 0.95L (1 qt). If it is at the full mark, use 0.47L (1/2 qt).

2. Run the engine for 15 minutes. Stop the engine and inspect all seal and gasket areas for leaks using the UV Diagnostic Inspection Kit. A clear bright yellow or orange area will identify the leak. For extremely small leaks, several hours may be required for the leak to appear.

3. At the end of test, make sure the oil level is within the upper and lower oil indicator marks. Remove oil as necessary if it registers above the full mark.

Leakage Points - Underhood

NOTE: Check for oil in the valley of the engine that may have accumulated on the engine front cover or ran through the valley drain hole on the right front of the engine.

Examine the following areas for oil leakage:

- Valve cover gaskets
- Cylinder head gaskets
- Engine front cover
- Oil level indicator tube
- Crankcase vent oil separator
- Turbocharger pedestal

Leakage Points - Under Engine, With Vehicle on Hoist

NOTE: Verify that the oil leak is not from the upper engine area.

Examine the following areas for oil leakage:

- Oil pan gaskets
- Oil pan sealer
- Engine front cover gasket
- Crankshaft front seal
- Crankshaft rear seal
- Oil filter adapter
- Oil cooler
- Engine Oil Pressure (EOP) sensor
- Engine Oil Temperature (EOT) sensor

Leakage Points - With Transmission and Flywheel Removed

Examine the following areas for oil leakage:

- Crankshaft rear seal
- Flexplate mounting bolt holes (with flexplate installed)
- Pipe plugs at the end of oil passages
- Core plugs

Oil leaks at crimped seams in sheet metal parts and cracks in cast or stamped parts can be detected when using the Diesel Engine Oil Dye method.