Removing the piston with connecting rod

Preliminary work 

• Refer to RELEASING THE OIL DRAIN PLUG
• Refer to REMOVING THE OIL FILTER ELEMENT
• Refer to REMOVING THE COMPLETE FRONT AXLE WITH THE ENGINE AND TRANSMISSION
• Refer to INSTALLING THE ENGINE ON THE ASSEMBLY JIG
• Refer to REMOVING FLYWHEEL
• Refer to REMOVING DRIVE BELT 
• Refer to REMOVING THE BELT TENSIONER 
• Refer to REMOVING THE AIR CONDITIONING COMPRESSOR (ENGINE REMOVED)
• Refer to REMOVING THE COOLANT PUMP
• Refer to RELEASING LEFT CHARGE AIR LINE PARTIALLY
• Refer to PARTIALLY RELEASING THE RIGHT CHARGE AIR LINE
• Refer to REMOVING THE COOLANT EXPANSION TANK FOR THE LOW-TEMPERATURE COOLANT CIRCUIT
• Refer to REMOVING BOTH CHARGE AIR COOLERS
• Refer to REMOVING RIGHT CLEAN AIR PIPE
• Refer to REMOVING LEFT CLEAN AIR PIPE
• Refer to REMOVING ALL IGNITION COILS
• Refer to REMOVING FUEL DELIVERY LINE
• Refer to REMOVING RIGHT HIGH-PRESSURE PUMP
• Refer to REMOVING LEFT HIGH PRESSURE PUMP
• Refer to PARTIALLY UNDOING WIRING HARNESS FROM RIGHT CYLINDER HEAD COVER
• Refer to RELEASING THE WIRING HARNESS SECTION FROM THE LEFT HAND CYLINDER HEAD COVER
• Refer to REMOVING RIGHT RAIL
• Refer to REMOVING THE HIGH-PRESSURE RAIL ON THE LEFT
• Refer to REMOVING THE INJECTORS FOR CYLINDERS 1 TO 4
• Refer to REMOVING THE INJECTORS FOR CYLINDERS 5 TO 8
• Refer to REMOVING VANOS SOLENOID ACTUATOR, EXHAUST OF CYLINDER BANK 1
• Refer to REMOVING THE VANOS SOLENOID ACTUATOR INTAKE OF CYLINDER BANK 1
• Refer to REMOVING VANOS SOLENOID ACTUATOR, EXHAUST OF CYLINDER BANK 2
• Refer to REMOVING VANOS SOLENOID ACTUATOR, INTAKE OF CYLINDER BANK 2
• Refer to REMOVING THE LEFT AND RIGHT EXHAUST TURBOCHARGER
• Refer to REMOVING FRONT HEAT SHIELD
• Refer to REMOVING THE OIL FEED LINE AT THE EXHAUST TURBOCHARGER FOR CYLINDERS 5 TO 8
• Refer to REMOVING RIGHT CYLINDER HEAD COVER
• Refer to REMOVING LEFT CYLINDER HEAD COVER
• Refer to REMOVING THE TIMING CASE COVER FROM THE CYLINDER HEAD OF CYLINDER BANK 2
• Refer to REMOVING THE SEALING CAP ON THE CYLINDER HEAD OF THE CYLINDER BANK 1
• Refer to MOVING THE CRANKSHAFT TO THE INSTALLATION POSITION TO ADJUST THE TIMINGS
• Refer to CHECKING THE VANOS ADJUSTER OF CYLINDER BANK 2
• Refer to RELAXING CHAIN TENSIONER ON BANK 2 FOR CHECKING OR SETTING TIMING
• Refer to REMOVING HYDRAULIC CHAIN TENSIONER OF CYLINDER BANK 2
• Refer to PRELOADING THE TIMING CHAIN OF CYLINDER BANK 2
• Refer to FIXING THE ENGINE IN THE INSTALLATION POSITION ON CYLINDER 1 (SET VALVE TIMINGS)
• Refer to REMOVING BOTH LEFT VANOS ADJUSTERS
• Refer to REMOVING SPECIAL TOOL FOR FIXING CAMSHAFTS IN POSITION ON BANK 2
• Refer to REMOVING SPECIAL TOOL TO PRETENSION TIMING CHAIN ON CYLINDER BANK 2
• Refer to REMOVING LEFT CYLINDER HEAD
• Refer to PARTIALLY RELEASING THE GUIDE TUBE FOR THE OIL DIPSTICK
• Refer to CHECKING THE VANOS ADJUSTER OF CYLINDER BANK 1
• Refer to RELIEVING THE CHAIN TENSIONER AT CYLINDER BANK 1 FOR CHECKING OR SETTING THE VALVE TIMINGS
• Refer to REMOVING HYDRAULIC CHAIN TENSIONER OF CYLINDER BANK 1
• Refer to PRELOADING THE TIMING CHAIN OF CYLINDER BANK 1
• Refer to FIXING THE ENGINE IN THE INSTALLATION POSITION ON CYLINDER 1 (SET VALVE TIMINGS)
• Refer to REMOVING BOTH RIGHT VANOS ADJUSTERS
• Refer to REMOVING SPECIAL TOOL FOR FIXING CAMSHAFTS ON BANK 1
• Refer to REMOVING THE SPECIAL TOOL TO PRETENSION THE TIMING CHAIN AT CYLINDER BANK 1
• Refer to REMOVING RIGHT CYLINDER HEAD
• Refer to REMOVING THE VIBRATION DAMPER
• Refer to REMOVING LOWER OIL PAN SECTION
• Refer to REMOVING OIL PUMP
• Refer to REMOVING FRONT AXLE DIFFERENTIAL
• Refer to REMOVING UPPER OIL SUMP SECTION, ENGINE REMOVED

• Twist the crankshaft (2)  into the position for disassembly.
• Unscrew both connecting rod bolts (1)  .
• Remove the connecting rod bearing cap (3)  with guide bearing shell.

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• Screw in the special tools 2 249 164  hand-tight into the threaded connection of the connecting rod bolts (1)  .
• Press out the piston with the connecting rod using special tool 2 249 164  .

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• Remove the piston and connecting rod in an upward direction.
• Lever the connecting rod bearing shell (1)  out of the connecting rod bearing cap (see arrows).

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• Lever out connecting rod bearing (1)  with Irox coating from the connecting rod (see arrows).

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• Measure the cylinder path.

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• Check the arrangement of the piston rings.

  Piston ring (1)  .

  Piston ring (2)  .

  Oil scraper ring (U-Flex design) (3)  .

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Check 

• Position micrometer in area (A)  and measure piston installation clearance transversely to piston pin.

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Result 

» Piston does not correspond to the specifications.

Measure

• Replace piston.
• Remove upper and middle piston ring (1)  with a piston ring pliers (2)  .

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• Remove oil scraper ring (2)  (U-Flex) by hand over the piston skirt (1)  .

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• Compare and evaluate the side clearance values with the setpoint values.
• Clean the ring zone on the piston.
• Insert the piston ring into the annular groove on the piston.

  Determine the side clearance values with feeler gauge (1)  .

Courtesy of BMW OF NORTH AMERICA, INC.

• Use the piston (1)  to push the upper and center piston ring in parallel to the last annular groove (see graphic).

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• Determine the end clearance, compare to the setpoint value and assess.

• Determine the gap on the piston ring (end clearance) with a suitable feeler gauge (1)  .

  If applicable, replace the piston rings.

Courtesy of BMW OF NORTH AMERICA, INC.