TPIM Cooling System Leak Testing

TESTING FOR LEAKS

ULTRAVIOLET LIGHT METHOD

A leak detection additive is available through the parts department that can be added to cooling system. The additive is highly visible under ultraviolet light (black light) (1). Pour one ounce of additive into the TPIM cooling system. Using the scan tool, cycle the coolant pump. Aim the commercially available black light tool at components to be checked. If leaks are present, black light will cause the additive to glow a bright green color.

PRESSURE TESTER METHOD

The TPIM cooling system at normal operating temperature. Recheck the system cold if the cause of coolant loss is not located during the warm examination.

Carefully remove the radiator pressure cap from the filler neck and check coolant level. Push down on cap to disengage it from the stop tabs. Wipe the inside of filler neck and examine the lower inside sealing seat for nicks, cracks, paint, and dirt. Inspect the coolant recover container hose for internal obstructions. Insert a wire through the hose to be sure it is not obstructed.

Inspect cams on the outside of filler neck. If the cams are damaged, seating of the pressure cap valve and tester seal will be affected.

Attach Pressure Tester 7700 and Adaptor on equivalent to radiator filler neck (1). Operate tester pump to apply 41 - 55 kPa (6 - 8 psi) pressure to the system. If hoses enlarge excessively or bulge while testing, replace as necessary. Observe the gauge pointer and determine the condition of the cooling system according to the following criteria:

Drops Quickly:Indicates that serious leakage is occurring. Examine system for external leakage. If leaks are not visible, inspect for internal leakage.

Holds Steady:If the pointer remains steady for two minutes, serious coolant leaks are not present in system. However, there could be an internal leak that does not appear with normal system test pressure. If it is certain that coolant is being lost and leaks cannot be detected, inspect for interior leakage or perform Internal Leakage Test. Refer to INTERNAL LEAKAGE INSPECTION.

Drops Slowly: Indicates a small leak or seepage is occurring. Examine all connections for seepage or slight leakage with a flashlight. Inspect radiator, hoses, gasket edges and heater. Seal small leak holes with a Sealer Lubricant (or equivalent). Repair leak holes and inspect system again with pressure applied