Cooling System, Checking For Leaks: Procedure
- Engine at operating temperature.
The Cooling System Is under Pressure When the Engine Is Warm. Risk of Scalding Due to Hot Steam and Hot Coolant.
Scalding the Skin and Other Parts of the Body Is Possible.
- Wear safety gloves.
- Wear protective eyewear.
- Reduce the pressure by covering the coolant expansion tank cap with a cloth and carefully opening it.
-- Open the coolant expansion tank cap.
-- Position the :VAG1274B with the :VAG1274/8 on the coolant expansion tank.
-- Generate approximately 1.0 bar (14.5 psi) pressure using the cooling system tester hand pump.
-- If the pressure falls, search for leaks and correct the malfunction.
Risk of Scalding Due to Hot Steam and Hot Coolant.
Scalding the Skin and Other Parts of the Body Is Possible.
- Reducing the pressure: press the pressure release valve on the cooling system tester until the pressure gauge displays a value of 0.
Pressure Relief Valve in Cap, Checking
Cap, Version 1:
-- Position the :VAG1274B with the :VAG1274B/15 on the cap.
-- Generate approximately 2.0 bar (29 psi) pressure using the cooling system tester hand pump.
Blue Cap
- The pressure must lower to 1.6 to 1.4 bar (23.20 to 20.30 psi) and stay there.
-- If the pressure relief valve does not react as specified, replace the cap.
Black Cap
- The pressure must lower to 1.8 to 1.6 bar (26.1 to 23.20 psi) and stay there.
-- If the pressure relief valve does not react as specified, replace the cap.
Cap, Version 2:
-- Position the :VAG1274B with the :VAG1274/9 on the cap.
-- Generate pressure with the cooling system tester hand pump.
Blue Cap
- The pressure release valve must open at 1.4 to 1.6 bar (20.30 to 23.20 psi).
-- If pressure relief valve does not open as specified, replace the cap.
Black Cap
- The pressure release valve must open at 1.6 to 1.8 bar (23.2 to 26.1 psi).
-- If pressure relief valve does not open as specified, replace the cap.