Fluid Leak Diagnosis

Fluid Leak Diagnosis

Special Tools

* J 28431-6 - Fluorescent Oil Dye - 6 1 oz

* J 42220 - Universal 12V Leak Detection Lamp

Dye and Black Light Method

Use the J 42220 - leak detection lamp and the J 28431-6 - oil dye to isolate the leak point. Fluid dye and black light kits are also available from various tool manufacturers. All transmissions that are diagnosed, that require replacement due to leakage, must be diagnosed with the leak dye and black light method.

1. Follow the manufacturer's instructions in order to determine the amount of dye to use.

2. Detect the leak with the black light.

3. Make the necessary repairs.

General Method

1. Verify that the leak is transmission fluid.

Caution:
Do not clean using brake cleaner or other reactive solvents as these solvents can damage rubber gaskets, seals and bushings.

2. Thoroughly clean the suspected leak area using a rag.

Note:
Do not idle vehicle, this will not actuate transmission systems, and do not drive the vehicle on the freeway as this will splatter oil inhibiting leak diagnosis.

3. Operate the vehicle for 15-20 minutes under city driving conditions until normal operating temperatures are reached.

4. Park the vehicle over clean paper or cardboard.

5. Shut OFF the engine.

6. Look for fluid spots on the paper.

7. Make the necessary repairs.

Powder Method

Caution:
Do not clean using brake cleaner or other reactive solvents as these solvents can damage rubber gaskets, seals and bushings.

1. Thoroughly clean the suspected leak area using a rag.

2. Apply an aerosol type leak tracing powder to the suspected leak area.

Note:
Do not idle vehicle, this will not actuate transmission systems, and do not drive the vehicle on the freeway as this will splatter oil inhibiting leak diagnosis.

3. Operate the vehicle for 15-20 minutes under city driving conditions until normal operating temperatures are reached.

4. Shut OFF the engine.

5. Inspect the suspected leak area.

6. Trace the leak path through the powder in order to find the source of the leak.

7. Make the necessary repairs.

Find the Cause of the Leak

Pinpoint the leak and trace the leak back to the source. You must determine the cause of the leak in order to repair the leak properly. For example, if you replace a gasket, but the sealing flange is bent, the new gasket will not repair the leak. You must also repair the bent flange. Before you attempt to repair a leak, check for the following conditions, and make repairs as necessary:

Gaskets

* Fluid level/pressure is too high

* Plugged vent or drain-back holes

* Improperly tightened fasteners

* Dirty or damaged 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, where applicable

* Incorrect gasket

Seals

* Fluid level/pressure is too high

* Plugged vent or drain-back holes

* Damaged seal bore

* Damaged or worn seal

* Improper installation

* Cracks in component

* Manual or output shaft surface is scratched, nicked, or damaged

* Loose or worn bearing causing excess seal wear