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Engine Oil Leak Inspection

ENGINE OIL LEAKS
Begin with a through visual inspection of the engine, particularly at the area of the suspected leak. If an oil leak source is not readily identifiable, the following steps should be followed:
1. Do not clean or degrease the engine at this time because some solvents may cause rubber to swell, temporarily stopping the leak.
2. Add an oil-soluble dye (use as recommended by manufacturer). Start the engine and let idle for approximately 15 minutes. Check the oil dipstick to be sure the dye is thoroughly mixed as indicated with a bright yellow color under a black light source.
3. Using a black light, inspect the entire engine for fluorescent dye, particularly at the suspected area of oil leak. If the oil leak is found and identified, repair.
4. If dye is not observed, drive the vehicle at various speeds for approximately 24 km (15 miles), and repeat previous step.
5. If the oil leak source is not positively identified at this time, proceed with the air leak detection test method as follows:
6. Disconnect the breather cap to air cleaner hose at the breather cap end. Cap or plug breather cap nipple.
7. Remove the PCV valve from the cylinder head cover. Cap or plug the PCV valve grommet.
8. Attach an air hose with pressure gauge and regulator to the dipstick tube.

CAUTION: Do not subject the engine assembly to more than 20.6 kPa (3 PSI) of test pressure.

9. Gradually apply air pressure from 1 psi to 2.5 psi maximum while applying soapy water at the suspected source. Adjust the regulator to the suitable test pressure that provide the best bubbles which will pinpoint the leak source. If the oil leak is detected and identified, repair.
10. If the leakage occurs at the rear oil seal area, refer to the Inspection for Rear Seal Area Leak.
11. If no leaks are detected, turn off the air supply and remove the air hose and all plugs and caps. Install the PCV valve and breather cap hose. Proceed to next step.
12. Clean the oil off the suspect oil leak area using a suitable solvent. Drive the vehicle at various speeds approximately 24 km (15 miles). Inspect the engine for signs of an oil leak by using a black light.