Remove the radiator cap, and install a cooling system pressure tester [A] on the filler neck.
Note. Wet the cap sealing surfaces with water or coolant to prevent pressure leaks.
Build up pressure in the system carefully until the pressure reaches 123 kPa (1.25 kg/cm2, 18 psi).
Caution! During pressure testing, do not exceed the pressure for which the system is designed. The maximum pressure is 123 kPa (1.25 kg/cm2, 18 psi).
Watch the gauge for at least 6 seconds.
★ If the pressure holds steady, the system is all right
★ If the pressure drops and no external source is found, check for Internal leaks. Droplets in the engine oil indicate internal leakage. Check the cylinder head gasket and the water pump.
Remove the pressure tester, replenish the coolant, and install the radiator cap.