Engine Oil Leaks

NOTE: When diagnosing engine oil leaks, the source of the leak must be positively identified prior to repair. If the vehicle is driven extensively between adding the fluorescent additive and performing the leak test, fan air or wind can spread the leaking oil and make identifying the location of the leak difficult.

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

Engine Oil Leaks -- Fluorescent Oil Additive Method

NOTE: If the factory fill engine oil with dye is present, change the engine oil and the oil filter prior to using the Dye-Lite® Oil-Based Fluid Dye (164-TP33200601).

Use the UV Long-Wave W/12-foot Cord and Alligator Clips (164-R3748) or Leak Tracker UV-LED Leak Detection Flashlight (164-TP8695) to carry out the following procedure for oil leak diagnosis.

Add 29.6 ml (1 oz) of Dye-Lite® Oil-Based Fluid Dye (164-TP33200601) to a minimum of 0.47L (1/2 qt) and a maximum of 0.95L (1 qt) engine oil. Thoroughly premix the oil based fluid dye or it will not have enough time to reach the crankcase, oil galleries and seal surfaces during this particular 15 minute test. The additive must be 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).
NOTE: For best results allow the customer to drive the vehicle for a day.

Run the engine for 15 minutes. Stop the engine and inspect all seal and gasket areas for leaks using the UV Leak Detector Kit. A fluoresces white area will identify the leak. For extremely small leaks, several hours may be required for the leak to appear.
At the end of the 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

Examine the following areas for oil leakage:

Valve cover gaskets
Cylinder head gaskets
Oil cooler, if equipped
Oil filter adapter
Engine front cover
Oil filter adapter and filter body
Oil level indicator tube connection
Engine Oil Pressure(EOP) switch

Leakage Points -- Under Engine, With Vehicle on Hoist

Examine the following areas for oil leakage:

Oil pan gaskets
Oil pan sealer
Engine front cover gasket
Crankshaft front seal
Crankshaft rear oil seal
Oil filter adapter and filter body
Oil cooler, if equipped

Leakage Points -- With Transmission and Flywheel Removed

Examine the following areas for oil leakage:

Crankshaft rear oil seal
Rear main bearing cap parting line
Flexplate mounting bolt holes (with flexplate installed)
Pipe plugs at the end of oil passages

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