Cooling System, Checking For Leaks: Notes

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Special Tools And Workshop Equipment Required

Cooling System Tester - Adapter:VAG1274/8
Cooling System Tester - Adapter:VAG1274/9
Cooling System Tester:VAG1274B

NOTE:

To perform the correct leak test, the check (self-test) of the :VAG1274B must be performed.

Check (Self-Test) of :VAG1274B

Fig 1: Special Tool VAG1274B

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-- Operate the :VAG1274B multiple times.

-- Create a pressure of 3.0 bar (43.51 psi) on the :VAG1274B .

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-- Observe the pressure on the pressure gauge of the :VAG1274B for 30 seconds.

If No Pressure Is Built or the Pressure Decreases:

The :VAG1274B is leaking and must not be used.

Cooling System, Checking for Leaks

Fig 2: Identifying Coolant Reservoir Cap

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Engine at operating temperature.

CAUTION:

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 reservoir cap -arrow-.

-- Position the :VAG1274B with the :VAG1274/8 on the coolant expansion tank.

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-- Generate approximately 1.5 bar (21.75 psi) pressure with cooling system tester hand pump.

The pressure must not drop more than 0.2 bar (2.9 psi) within 10 minutes.

-- If the pressure falls more than 0.2 bar (2.9 psi), search for leaks and correct the problem.

NOTE:

The pressure decrease of 0.2 bar (2.9 psi) within 10 minutes is a condition of the cooling of the coolant. The colder the engine the more the pressure decrease. If necessary repeat the test with the engine cold.