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1125530 Removing and installing/replacing all pistons (N51): Notes

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WARNING: Protective goggles must be worn when working on the piston pin circlip.
IMPORTANT: If pistons, conrods and bearing shells are reused, they must be reinstalled in the same places.
Individual conrod replacement is not permitted; they are classified according to weight categories.
Conrods and conrod bearing caps are denoted with the same pairing letters; mixing them up will result in engine damage.
Piston and piston pins are paired and must not be fitted individually.

Necessary preliminary tasks: 

NOTE: In event of heavy oil carbon residue:
Carefully remove oil carbon residue from cylinder wall.
NOTE: Illustrations show N46.
Fig 1: Locating Oil Carbon Residue
G04751123Courtesy of BMW OF NORTH AMERICA, INC.

Do not  release screw (1).

Oil spray nozzle (2) must not be maladjusted or bent (risk of damage). 

READJUST  if necessary.

Fig 2: Identifying Screw And Oil Spray Nozzle
G04751124Courtesy of BMW OF NORTH AMERICA, INC.

Release conrod bolts (1).

Tightening torque, 11 24 1AZ .

Remove conrod bearing cap (2) in direction of arrow.

IMPORTANT: Conrods and conrod bearing caps are denoted with the same pairing letters; mixing them up will result in engine damage.
Fig 3: Removing Connecting Rod Bearing Cap
G04751125Courtesy of BMW OF NORTH AMERICA, INC.

Attach special tool 11 8 330 ASSEMBLY TOOL in conrod big end.

Press out conrod and piston to cylinder head side.

IMPORTANT: Risk of damage  to oil spray nozzle.
Fig 4: Identifying Special Tool (11 8 330)
G04751126Courtesy of BMW OF NORTH AMERICA, INC.