Cooling System: Testing and Inspection

Cooling System Pressure Test

The content of this article reflects the changes identified in TSB - LTB00109

NOTE: This following procedure will enable the cooling system to be pressure tested for condition and leaks. Stage 1 will check the expansion tank cap register seal and the cap for leaks. Stage 2 will check the the entire cooling system.

NOTE: It will be necessary to use the cooling system test kit, Part Number LR-218, which is available under the equipment program.

1. Examine the coolant hoses for signs of cracking, distortion and security of the hose connections.

WARNING: Since injury such as scalding could be caused by escaping steam or coolant, allow the vehicle cooling system to cool prior to carrying out this procedure.

2. Disconnect the coolant expansion tank bleed hose.
^ Release the clip.
3. Install the 'T' piece adapter (part of the cooling system test kit) between the coolant expansion tank and the coolant bleed hose.
^ Secure with the 2 clips.
4. Install the coolant pressure pump assembly.
^ Connect to the 'T' piece.





5. Pressurize the cooling system.
^ Slowly pressurize the cooling system to 1.0 bar (100 kPa) (14.5 psi).
^ Check the pressure remains above 0.9 bar (90 kPa) (13 psi) after waiting for 30 seconds.
^ During the pressure drop check, listen for a hissing noise from the expansion tank cap.

NOTE: If the coolant expansion tank cap is found to be leaking, replace the cap.

6. Depressurize the cooling system.
^ Disconnect the 'T' piece.
^ Connect the coolant expansion tank bleed hose.
^ Secure the clip.

WARNING: Since injury such as scalding could be caused by escaping steam or coolant, allow the vehicle cooling system to cool prior to carrying out this procedure.

7. Remove the coolant expansion tank cap.

NOTE: This adapter is part of the cooling system test kit.

8. Install adapter K83 to the coolant expansion tank.
^ Clean the component mating faces.
^ Lubricate the seal.
9. Install the coolant pressure pump assembly.
^ Slowly pressurize the cooling system to 1.5 bar (150kPa) (22 psi), check the pressure over a 5 minute period. A small pressure decay of approximately 0.15 bar (15 kPa) (1 psi) over the first minute is normal, as the air in the expansion tank cools.
^ If the pressure continues to drop after the initial tolerance, there is a coolant leak.





10. Depressurize and remove the pressure pump and gauge.
^ Install the coolant expansion tank cap.