Oil Cooler: Testing and Inspection

Oil Cooler, Checking for Leaks

Special tools, testers and auxiliary items required

• Refractometer (T10007)

• Hose Clamps Up to 25 mm Dia. (3094)

• Cooling System Tester (V.A.G 1274)

• Adapter (V.A.G 1274/8)

• Hose Clip Pliers (VAS 6362)

• Drip Tray for VAS 6100 (VAS 6208)

• Torque Wrench (5-50 Nm) (V.A.G 1331)

• Expansion Tank (1K0 121 407 A bzw. 6Q0 121 407 A bzw. 1J0 121 407 B)

• Sealing Plugs (191 211 343)

• Sealing Cap (1J0 121 324)

• Coolant Hose (251 265 056)

Test Conditions

• Engine must be cold.

Test Sequence

- Remove the noise insulation.

- Clamp off the coolant hoses from the oil cooler using the hose clamps up to 25 mm dia. (3094).






- Loosen the hose clamps - arrows - using hose clip pliers (VAS 6362).

• Collect any leaking fluid using the drip tray for VAS 6100 (VAS 6208).

- Disconnect the coolant hoses from the oil cooler.

- Install the cap - 5 - on the rear fitting of the oil cooler - 4 -.






- Secure the sealing cap - 2 - on the expansion tank - 1 - fitting.

- Install the coolant hose - 3 - to the oil cooler and the coolant reservoir.

- Slowly fill the coolant up to the upper mark in the hatched area on the expansion tank.






- Install the cooling system tester (V.A.G 1274) with adapter (V.A.G 1274/8) to the expansion tank.

- Generate a pressure of approximately 1.6 bar using the cooling system tester (V.A.G 1274).

- Watch the pressure decrease on the pressure gauge.

• The pressure must not fall within 10 minutes.

If the pressure drops:

- Replace the oil cooler => [ Oil Filter Bracket and Oil Cooler Overview ] Oil Filter Bracket and Oil Cooler Overview.

Install in reverse order of removal. When doing this note the following:

- Check the coolant level; fill if necessary. Refer to => [ Draining and Filling ] Draining and Filling.