Cylinder head disassembled

Check evenness of cylinder head lower face with a standard straightedge (1).

NOTE: Maximum deviation from flatness: longitudinal 0.10 mm.

Fig 1: Checking Evenness Of Cylinder Head Lower Face With Standard Straightedge - Longitudinal

Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: Maximum deviation from flatness: transversal 0.05 mm.

Machining limit: See CYLINDER HEAD WITH VALVE SEAT COVER or CYLINDER HEAD WITH COVER

Fig 2: Checking Evenness Of Cylinder Head Lower Face With Standard Straightedge - Transversal
Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: A cylinder head gasket (+REP) 0.3 mm thicker than usual can be obtained for machined (resurfaced) cylinder heads.

Fig 3: Identifying Cylinder Head Gasket (+REP)

Courtesy of BMW OF NORTH AMERICA, INC.