Cooling System, Checking For Leaks

Cooling System, Checking for Leaks

=> [ Pressure Relief Valve in Cap, Checking ]

Special tools, testers and auxiliary items required

• Cooling system tester (VAG 1274)

• Adapter (VAG 1274/8)

• Adapter (VAG 1274/9)

Test Conditions

• Engine at operating temperature.

Test Sequence

CAUTION!
Hot steam may escape when opening the expansion tank cap. Wear protective goggles and protective clothing to prevent damage to your eyes and from scalding. Cover the cap with a cloth and open very carefully.

- Open the cap of the coolant expansion tank.

- Install the (VAG 1274) with the (VAG 1274/8 ) to the expansion tank.





- Generate a positive pressure of approximately 1.0 bar using the (VAG 1274).

If the pressure drops:

- Search for leaking areas and repair the malfunction.

Pressure Relief Valve in Cap, Checking





- Install the (VAG 1274) with the (VAG 1274/9 ) on the cap.

- Generate a positive pressure of maximum 1.4 bar using the ( VAG 1274).

Pressure relief valve must not open yet.

If pressure relief valve opens prematurely:

- Replace the cap.

- Increase the pressure to above 1.6 bar.

Pressure relief valve must open.

If the pressure relief valve does not open:

- Replace the cap.