Make sure the coolant level reaches the radiator filler neck.
Fig. 2.4. Connecting the tester to check the radiator cap valve
Connect the radiator cap valve tester to the radiator filler neck and apply a pressure of 150 kPa. Maintaining this pressure for 2 minutes, check for coolant leaks from the radiator, hose connections or the cooling system hoses themselves (Fig. 2.4).
Note: Coolant may be extremely hot. Do not remove the radiator cap as this will cause steam to escape and hot or boiling fluid to splash out, possibly causing injury to service personnel. Allow the engine to cool before working on the cooling system.
Thoroughly remove moisture from the surface of all parts being checked for leaks.
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When removing the radiator cap valve tester from the radiator neck, be careful not to splash any coolant.
When connecting and disconnecting the tester, as well as during testing, be careful not to deform the radiator filler neck.
If leaks are present, repair or replace the appropriate part.