11 12 729 Checking Cylinder Head For Leaks (N51)

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Special tools required:

For the following special tools, refer to ENGINE - SPECIAL TOOLS (N51) .

11 4 341
11 4 342
11 4 344
11 4 345

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 . See 11 12 100 REMOVING AND INSTALLING/SEALING CYLINDER HEAD (N51) .
Remove all engine valves . See 11 34 552 REMOVING AND INSTALLING OR REPLACING ALL VALVES (N51) .

NOTE: Observe mounting of special tool 11 4 341 on cylinder. See Fig 1. Secure special tool 11 4 341 with bolts 11 4 345 to 25 Nm.

Installation:

1 cyl is marked.

Fig 1: Identifying Special Tool (11 4 341)

Courtesy of BMW OF NORTH AMERICA, INC.

Fit special tool 11 4 342 with bolts (1), insert knurled screw in direction of arrow. See Fig 2.

Sealing flange must rest flat.

Fig 2: Inserting Knurled Screw

Courtesy of BMW OF NORTH AMERICA, INC.

Secure special tool 11 4 344 with bolts (1). See Fig 3.

NOTE: Compressed air at valve max. 3 bar.
Heat cylinder head to 60°.
Check for bubble formation in a water bath.

Fig 3: Identifying Special Tool With Bolts

Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.