11 12 729 Checking cylinder head for water leaks (N55)

2011 BMW 135i 2D Convertible, Automatic DCTSECTION 11 12 729 Checking cylinder head for water leaks (N55)

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: 

Fit special tool 11 7 190 .

Installation note: 

Secure special tool to 15 Newton meters.

Fig 1: Identifying Special Tool (11 7 191)
G09844271Courtesy of BMW OF NORTH AMERICA, INC.

Fit special tool 11 4 342 with screws (1). Screw in knurled screw in direction of arrow.

Sealing flange must rest flat.

Fig 2: Identifying Special Tool (11 4 342)
G04751057Courtesy of BMW OF NORTH AMERICA, INC.

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

NOTE: Compressed air at valve max. 3 bar.
Heat cylinder head to 60 °.
Check for bubble formation in a water bath.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.