Cooling System: Testing and Inspection
Cooling System, Checking for Leaks
Special tools, testers and auxiliary items required
• Cooling system tester (V.A.G 1274)
• Adapter (V.A.G 1274/8)
• Adapter (V.A.G 1274/9)
Procedure
• Engine at operating temperature.
CAUTION!
Cover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.
- Open cap of coolant expansion tank.
- Position cooling system tester (V.A.G 1274 ) with adapter (V.A.G 1274/8) on expansion tank.
- Generate a positive pressure of approximately 1.0 bar using hand pump of cooling system tester.
If pressure drops:
- Search for leaking areas and repair malfunction.
Pressure relief valve in cap, checking
- Position cooling system tester (V.A.G 1274 ) with adapter (V.A.G 1274/9) on cap.
- Generate a positive pressure using hand pump of cooling system tester.
• The pressure release valve must open at a positive pressure of 1.4 to 1.6 bar.
If check-valve does not open as indicated:
- Replace cap.