Cylinder Head Assembly: Testing and Inspection

11 12 729 - Checking cylinder head for water leaks (N12)





Special tools required:
- 11 9 521 11 9 520 Pressure-Testing Fixture
- 11 9 522 11 9 520 Pressure-Testing Fixture
- 11 9 523 11 9 520 Pressure-Testing Fixture





Necessary preliminary tasks:
- Remove cylinder head.
- Disassemble cylinder head.





Install special tool 11 9 521 11 9 520 Pressure-Testing Fixture with special tool 11 9 523 11 9 520 Pressure-Testing Fixture.

Installation:
Install special tool 11 9 521 11 9 520 Pressure-Testing Fixture so that all water ducts are sealed.





Secure special tool 11 9 523 11 9 520 Pressure-Testing Fixture to 25 Nm.





Screw special tool 11 9 522 11 9 520 Pressure-Testing Fixture into place with existing screws (1 and 3) of coolant thermostat.
Sealing flange must rest flat.

Note:
Compressed air at valve (2) must not exceed 3 bar.
Heat cylinder head to 60°.
Visually check for bubble formation in a water bath.





Assemble engine.