Cooling System: Testing and Inspection
Cooling System, Checking for Leaks
Special tools, testers and auxiliary items required
• Cooling System Tester (V.A.G 1274 A)
• Adapter (V.A.G 1274/8)
• Adapter (V.A.G 1274/9)
Procedure
• Engine at operating temperature.
Risk of scalding due to hot steam and hot coolant.
• When the engine is warm the cooling system is under pressure.
• Reduce pressure by covering coolant reservoir cap with a cloth and carefully opening.
- Open cap of coolant expansion tank.
- Position (V.A.G 1274 A) with (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 the pressure drops:
- Search for leaking areas and repair the malfunction.
Pressure relief valve in cap, checking
- Position (V.A.G 1274 A) with (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 1.4 to 1.6 bar.
If check-valve does not open as indicated:
- Replace cap.