LEMON Manuals: Even more car manuals for everyone
Home >> BMW >> 2012 >> 640i 2D Convertible >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Assembly And Cylinder Head - Repair - F12 >> Cylinder Head >> 11 12 729 Checking cylinder head for watertightness (N63)

11 12 729 Checking cylinder head for watertightness (N63)

Special tools required: 

Necessary preliminary work: 

NOTE: Set of special tools 11 8 080 can be used for cylinder bank 1 to 4 and cylinder bank 5 to 8.

Position special tool 11 8 081 on cylinder head.

Fig 1: Positioning Special Tool 11 8 081 On Cylinder Head
G10041626Courtesy of BMW OF NORTH AMERICA, INC.

Insert special tool 11 8 083 and tighten in sequence (1 to 10) in several steps.

Tightening torque: 25 Nm 

Fig 2: Cylinder Head Bolts Tightening/Loosening Sequence
G10041627Courtesy of BMW OF NORTH AMERICA, INC.

Remove vent screw (1).

Tightening torque: 11 12 8 AZ .

Installation note: 

Replace sealing ring.

Fig 3: Identifying Vent Screw
G10041628Courtesy of BMW OF NORTH AMERICA, INC.
IMPORTANT: Max: 0.8 Nm.

Screw in special tool 11 8 082 with suitable tool and special tool 00 9 250, see 00 9 460 to 0.8 Nm.

Connect compressed air hose with pressure gauge.

Immerse cylinder head in a water bath. Inspection pressure 4.0 bar.

Check cylinder head for escaping air (cracks).

Fig 4: Identifying Special Tool (11 8 082)
G10041629Courtesy of BMW OF NORTH AMERICA, INC.
NOTE: If necessary, add cleaning agent to water bath.
Assemble engine.