11 12 729 Checking cylinder head for water leaks (N14)

Special tools required:

IMPORTANT: Pressure-test cylinder head to max. 3 bar.
Heat cylinder head to 60 °.
Check for bubble formation in a water bath.

Necessary preliminary tasks:

Remove CYLINDER HEAD .
Disassemble cylinder head. See REMOVING/INSTALLING/REPLACING INTAKE CAMSHAFT (N14) , REMOVING/INSTALLING/REPLACING EXHAUST CAMSHAFT (N14) , and REMOVING/INSTALLING/REPLACING ALL CAM FOLLOWERS (N14) .

Mount special tool 11 9 521 with bolts 11 9 523 .

Installation:

Install special tool 11 9 521 so that all water ducts are sealed.

Fig 1: Sealing Water Ducts Using Special Tool (11 9 521)

Courtesy of BMW OF NORTH AMERICA, INC.

Secure bolts 11 9 523 to 25 Nm .

Fig 2: Securing Bolts (11 9 523)

Courtesy of BMW OF NORTH AMERICA, INC.

Screw special tool 11 9 522 into place with existing screws (1 and 3) of coolant thermostat.

NOTE: Sealing flange 11 9 522 must rest flat.
Compressed air at valve (2) must not exceed 3 bar .
Heat cylinder head to 60 °.
Check for bubble formation in a water bath.

Fig 3: Screws, Valve And Special Tool (11 9 522)

Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.