Make sure the coolant level reaches the radiator filler neck.
Pic. 2.5. Connecting a tester to check the radiator cap valve
Connect a radiator cap valve tester to the radiator filler neck and apply a pressure of 140 kPa. Holding the specified pressure for 2 minutes, check for coolant leaks from the radiator, hose connections, or the cooling system hoses themselves (pic. 2.5).
Note. The coolant can be extremely hot. Do not remove the radiator cap as this will release steam and splatter hot or boiling liquid and may cause injury to service personnel. Start working on the cooling system only after the engine has cooled down.
Thoroughly remove moisture from the surface of all parts being checked for leaks.
When removing the radiator cap valve tester from the radiator neck, be careful not to splash coolant.
When connecting and disconnecting the tester, as well as during the test, be careful not to deform the radiator filler neck.
If there are leaks, repair or replace the related part.