Remove the radiator cap.
Clean the seating surface of the radiator cap and upper radiator hose.
Pic. 2.212. Compressometer connection
To check the tightness of the radiator cap, connect a compression tester to the filler neck of the expansion tank (pic. 2.212).
Note. When connecting the radiator cap to the compression gauge, apply water or engine coolant to the cap seal.
Pressurize the radiator to the specified pressure.
Pressure: 127 kPa.
Make sure the pressure doesn't drop. Otherwise, check the system for coolant leakage.
– If the coolant leak is at the top of the hose fitting, replace the top hose and clamp.
– If the coolant leak is in the main part of the radiator, replace the radiator.