Cooling System: Testing and Inspection

Cooling System, Checking for Leaks

Special tools, testers and auxiliary items required

• Cooling system tester (VAG 1274B)

• Adapter (VAG 1274/8)

• Adapter (VAG 1274/9)

--> [ Pressure Relief Valve in Cap, Checking ].

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 eyes and scalding. Cover the cap with a cloth and open very carefully.

- Open the coolant expansion tank cap.

- Install the (VAG 1274/8) onto the coolant expansion tank.

- Clamp the (VAG 1274B/1) in the (VAG 1274/8).

- Connect the (VAG 1274B/1) to the (VAG 1274B) using the connecting hose.





- Generate a positive pressure of approximately 1.0 bar using hand pump of (VAG 1274B).

DANGER!
Risk of scalding! Reduce the pressure before disconnecting the (VAG 1274B) from the connecting hose or the (VAG 1274B/1). To do this, press the pressure release valve on the (VAG 1274B) until the manometer displays 0.

If the pressure drops:

- Search for leaking areas and repair the malfunction.

Pressure Relief Valve in Cap, Checking

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

- Open the coolant expansion tank cap.

- Install the cap to the (VAG 1274/9).

- Clamp the (VAG 1274B/1) in the (VAG 1274/9).

- Connect the (VAG 1274B/1) to the (VAG 1274B) using the connecting hose.





- Operate the (VAG 1274B):

• The pressure release valve must open at 1.4 to 1.6 bar.