Engine Oil Leak Diagnosis

OIL LEAK DIAGNOSIS

Most oil leaks are easily located and repaired by visually finding the leak and replacing or repairing the necessary parts. On some occasions, a fluid leak may be difficult to locate or repair. The following procedure may help in locating and repairing most leaks.

FINDING THE LEAK

1. Identify the fluid, determine whether it is engine oil, automatic transmission fluid, power steering fluid, etc.

2. At what point is the fluid leaking from? After running the vehicle at normal operating temperature, park the vehicle over a large sheet of paper. After a few minutes, you should be able to find the approximate location of the leak by the drippings on the paper.

3. Visually check around the suspected component. Check around all gasket mating surfaces for leaks. A mirror is useful for finding leaks in areas that are hard to reach.

4. If the leak still cannot be found, it may be necessary to clean the suspected area with a degreaser, steam or spray solvent. Clean the area, then dry the area. Operate the vehicle for several miles at normal operating temperature and varying speed. After operating the vehicle, visually check the suspected component. If you still cannot locate the leak, try using the powder or black light and dye method.

POWDER METHOD

1. Clean the suspected area.

2. Apply an aerosol-type powder (such as foot powder) to the suspected area.

3. Operate the vehicle under normal operating conditions.

4. Visually inspect the suspected component. You should be able to trace the leak path over the white powder surface to the source.

BLACK LIGHT AND DYE METHOD

1. Pour specified amount of dye into leaking component.

2. Operate the vehicle under normal operating conditions as directed in the kit.

3. Direct the light toward the suspected area. The dyed fluid will appear as a yellow path leading to the source.

REPAIRING THE LEAK

Once the leak has been pinpointed and traced back to its source, the cause of the leak must be determined in order for it to be repaired properly. If a gasket is replaced, but the sealing flange is bent, the new gasket will not repair the leak. The bent flange must be repaired also. Before attempting to repair a leak, check to be sure that the following conditions are correct as they may cause a leak.

GASKET LEAKS

Check for:

^ High fluid level or high oil pressure.

^ Plugged ventilation filter or valve.

^ Improperly tightened fasteners or dintyldamaged threads.

^ Warped flanges or sealing surface.

^ Scratches, burrs or other damage to the sealing surface.

^ Damaged or worn gasket.

^ Cracking or porosity of the component.

^ Improper sealant used, or no sealant where required.

SEAL LEAKS

Check for:

^ High fluid level or high oil pressure.

^ Plugged ventilation filters, or valve.

^ Damaged seal bore (scratched, burred or nicked).

^ Damaged or worn seal.

^ Improper installation.

^ Cracks in component.

^ Shaft surface scratched, nicked or damaged.

^ Loose or worn bearing causing excess seal wear.