A/T Fluid Cooler Cleaning

A/T FLUID COOLER

A/T Fluid Cooler Cleaning

Whenever an A/T is repaired, overhauled, or replaced, the A/T fluid cooler mounted in the radiator must be inspected and cleaned.
Metal debris and friction material, if present, can become trapped in the A/T fluid cooler. This debris can contaminate the newly serviced A/T or, in severe cases, can block or restrict the flow of A/T fluid. In either case, malfunction of the newly serviced A/T may result.
Debris, if present, may build up as A/T fluid enters the cooler inlet. It will be necessary to back flush the cooler through the cooler outlet in order to flush out any built up debris.

A/T FLUID COOLER CLEANING PROCEDURE
1. Position a drain pan under the A/T inlet and outlet fluid cooler tube to cooler hose connection.
2. Put a different color matching mark on each cooler tube to cooler hose connection to aid in assembly.

CAUTION:
Use paint to make the matching mark. Do not damage the tubes or hose.

3. Disconnect the fluid cooler inlet and outlet rubber hoses from the steel cooler tubes.

NOTE:
Replace the cooler hoses if rubber material from the hose remains on the tube fitting.
4. Drain any A/T fluid from the cooler hose.

5. Insert the extension adapter hose of a can of Transmission
Cooler Cleaner (Nissan P/N 999MP-AM006) into the cooler outlet hose.

CAUTION:
- Wear safety glasses and rubber gloves when spraying the
Transmission Cooler Cleaner.
- Spray cooler cleaner only with adequate ventilation.
- Avoid contact with eyes and skin.
- Do not breath vapors or spray mist.
6. Hold the hose and can as high as possible and spray Transmission Cooler Cleaner in a continuous stream into the cooler outlet hose until fluid flows out of the cooler inlet hose for 5 seconds.

7. Insert the tip of an air gun into the end of the cooler outlet hose.
8. Wrap a shop rag around the tip of the air gun and the cooler outlet hose.
9. Blow compressed air regulated to 5 - 9 kg/cm2 (70 - 130 psi) through the cooler outlet hose for 10 seconds to force out any remaining fluid.
10. Repeat steps 5 through 9 three additional times.
11. Position an oil pan under the banjo bolts that connect the fluid cooler tubes to the A/T.
12. Remove the banjo bolts.
13. Flush each steel line from the cooler side back toward the A/T by spraying Transmission Cooler Cleaner in a continuous stream for 5 seconds.
14. Blow compressed air regulated to 5 - 9 kg/cm2 (70 - 130 psi) through each steel line from the cooler side back toward the A/T for 10 seconds to force out any remaining fluid.
15. Ensure all debris is removed from the steel cooler lines.
16. Ensure all debris is removed from the banjo bolts and fittings.
17. Perform A/T fluid cooler diagnosis procedure.

A/T FLUID COOLER DIAGNOSIS PROCEDURE

NOTE:
Insufficient cleaning of the cooler inlet hose exterior may lead to inaccurate debris identification.
1. Position a drain pan under the A/T inlet and outlet fluid cooler tube to cooler hose connection.
2. Clean the exterior and tip of the cooler inlet hose.
3. Put a different color matching mark on each cooler tube to cooler hose connection to aid in assembly.

CAUTION:
Use paint to make the matching mark. Do not damage the tubes or hose.

4. Disconnect the fluid cooler inlet and outlet rubber hoses from the steel cooler tubes.

NOTE:
Replace the cooler hoses if rubber material from the hose remains on the tube fitting.

7. Tie a common white, basket-type coffee filter to the end of the cooler inlet hose.
8. Insert the tip of an air gun into the end of the cooler outlet hose.

9. Wrap a shop rag around the air gun tip and end of cooler outlet hose.
10. Blow compressed air regulated to 5 - 9 kg/cm2 (70 - 130 psi) through the cooler outlet hose to force any remaining A/T fluid into the coffee filter.
11. Remove the coffee filter from the end of the cooler inlet hose.
12. Perform A/T fluid cooler inspection. Refer to A/T Fluid Cooler Cleaning.

A/T FLUID COOLER INSPECTION PROCEDURE
1. Inspect the coffee filter for debris.

a. If small metal debris less than 1mm (0.040 in) in size or metal powder is found in the coffee filter, this is normal. If normal debris is found, the A/T fluid cooler/radiator can be re-used and the procedure is ended.
b. If one or more pieces of debris are found that are over 1mm

(0.040 in) in size and/or peeled clutch facing material is found in the coffee filter, the fluid cooler is not serviceable. The A/T fluid cooler/radiator must be replaced and the inspection procedure is ended. Refer to Removal and Installation.

A/T FLUID COOLER FINAL INSPECTION
After performing all procedures, ensure that all remaining oil is cleaned from all components.