11 12 729 Check cylinder head for watertightness (M57T2)

Necessary preliminary tasks:

Seal coolant openings with special tool kit 11 6 400 consisting of special tools 11 6 401/11 6 402/11 6 403/11 6 404/11 6 406/11 6 407/11 6 408.

NOTE: Special tool 11 6 407 is one set.

Use the old cylinder head bolts to secure the special tools 11 6 401/11 6 402 to the cylinder head.

Fig 1: Sealing Coolant Openings Using Special Tools (11 6 401/406/407/408)

Courtesy of BMW OF NORTH AMERICA, INC.

Immerse cylinder head in a water bath.

Test pressure: 4.5 bar.

Check cylinder head for escaping air (cracks).

NOTE: If necessary, relieve water bath with cleaning agent.

Fig 2: Checking Cylinder Head Escaping Air (Cracks)

Courtesy of BMW OF NORTH AMERICA, INC.