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Cylinder Block: Installation: Notes

WARNING: This page is about a different variant/trim than selected.
  1. Install the cylinder block LH to the engine stand.
  2. Apply engine oil to the crankshaft bearing, and install the crankshaft bearing to the cylinder block.
    CAUTION: When performing the operation of the cylinder block RH, be careful of the following.
    1. Place a wood board wrapped with a waste cloth to prevent the knock pin damage and to stabilize the cylinder block before work.
    2. Be careful not to scratch the mating surface of cylinder block during work.
    G09480561Courtesy of SUBARU OF AMERICA, INC.
  3. Install O-rings to the cylinder block LH.
    NOTE: Use new O-rings.
    G09480559Courtesy of SUBARU OF AMERICA, INC.
  4. Apply engine oil to the crankshaft journal, and set the crankshaft to cylinder block LH.
    G09480563Courtesy of SUBARU OF AMERICA, INC.
  5. Apply liquid gasket to the mating surface of cylinder block RH as shown in the figure.
    CAUTION:
    • Place a wood board wrapped with a waste cloth to prevent the knock pin damage and to stabilize the cylinder block before work.
    • Be careful not to scratch the mating surface of cylinder block during work.
    • Do not let the liquid gasket overflow to the oil passage and crankshaft bearing portions, because the engine seizure may result.
    NOTE:
    • Before applying liquid gasket, degrease the old liquid gasket seal surface of the cylinder block RH and cylinder block LH.
    • Install within 5 min. after applying liquid gasket.

    Liquid gasket: 

    THREE BOND 1217G (Part No. K0877Y0100), THREE BOND 1217H or equivalent

    Liquid gasket applying diameter: 

    Mating surfaces other than ranges A, B and C 

    1±0.5 mm (0.0394±0.0197 in)

    Mating surfaces of ranges A and C 

    4±0.5 mm (0.1575±0.0197 in)

    Mating surfaces of range B 

    3.2±0.5 mm (0.1260±0.0197 in)

    G13259297Courtesy of SUBARU OF AMERICA, INC.
  6. Install the cylinder block RH to the cylinder block LH.
  7. Join the cylinder blocks.
    1. Apply a coat of engine oil to the washers and cylinder block mounting bolt threads.
      NOTE: To prevent mixture of engine oil into the water jacket, do not apply a large amount.
    2. Tighten all mounting bolts with a torque of 35 N.m (3.6 kgf-m, 25.8 ft-lb) in numerical order as shown in the figure.
      CAUTION: When tightening the mounting bolts with specified torque, hold the cylinder block LH while not holding the cylinder block RH to ensure the joint accuracy of the cylinder block.
      Fig 1: Cylinder Block Mounting Bolts With (Tightening Sequence)
      G09480565Courtesy of SUBARU OF AMERICA, INC.
    3. Loosen all mounting bolts by 180° in numerical order as shown in the figure.
      CAUTION: When loosening the mounting bolts, hold the cylinder block LH while not holding the cylinder block RH to ensure the joint accuracy of the cylinder block.
      Fig 2: Cylinder Block Mounting Bolts With (Loosening Sequence)
      G09480558Courtesy of SUBARU OF AMERICA, INC.
    4. Tighten all mounting bolts with a torque of 35 N.m (3.6 kgf-m, 25.8 ft-lb) in numerical order as shown in the figure.
      CAUTION: When tightening the mounting bolts with specified torque, hold the cylinder block LH while not holding the cylinder block RH to ensure the joint accuracy of the cylinder block.
      Fig 3: Cylinder Block Mounting Bolts With (Tightening Sequence)
      G09480565Courtesy of SUBARU OF AMERICA, INC.
    5. Loosen the mounting bolts (4 places) by 180° in numerical order as shown in the figure.
      CAUTION: When loosening the mounting bolts, hold the cylinder block LH while not holding the cylinder block RH to ensure the joint accuracy of the cylinder block.
      Fig 4: Cylinder Block Mounting Bolts With (Loosening Sequence) (4 Place)
      G09480568Courtesy of SUBARU OF AMERICA, INC.
    6. Tighten the mounting bolts (4 places) with a torque of 17 N.m (1.7 kgf-m, 12.5 ft-lb) in numerical order as shown in the figure.
      CAUTION: When tightening the mounting bolts with specified torque, hold the cylinder block LH while not holding the cylinder block RH to ensure the joint accuracy of the cylinder block.
      Fig 5: Cylinder Block Mounting Bolts With (Tightening Sequence) (4 Place)
      G09480569Courtesy of SUBARU OF AMERICA, INC.
    7. Using angle gauge, tighten the mounting bolts (4 places) with specified angle in numerical order as shown in the figure.
      CAUTION: When tightening the mounting bolts with specified angle, hold the cylinder block LH while not holding the cylinder block RH to ensure the joint accuracy of the cylinder block.

      Tightening angle: 

      60°±2°

      Fig 6: Cylinder Block Mounting Bolts With (Tightening Sequence) (4 places)
      G09480570Courtesy of SUBARU OF AMERICA, INC.
    8. Loosen the mounting bolts (6 places) by 180° in numerical order as shown in the figure.
      CAUTION: When loosening the mounting bolts, hold the cylinder block LH while not holding the cylinder block RH to ensure the joint accuracy of the cylinder block.
      Fig 7: Cylinder Block Mounting Bolts With (Loosening Sequence) (6 Places)
      G09480571Courtesy of SUBARU OF AMERICA, INC.
    9. Tighten the mounting bolts (6 places) with a torque of 17 N.m (1.7 kgf-m, 12.5 ft-lb) in numerical order as shown in the figure.
      CAUTION: When tightening the mounting bolts with specified torque, hold the cylinder block LH while not holding the cylinder block RH to ensure the joint accuracy of the cylinder block.
      Fig 8: Cylinder Block Mounting Bolts With (Tightening Sequence) (6 Places)
      G09480572Courtesy of SUBARU OF AMERICA, INC.
    10. Using angle gauge, tighten the mounting bolts (6 places) with specified angle in numerical order as shown in the figure.
      CAUTION: When tightening the mounting bolts with specified angle, hold the cylinder block LH while not holding the cylinder block RH to ensure the joint accuracy of the cylinder block.

      Tightening angle: 

      60°±2°

      Fig 9: Cylinder Block Mounting Bolts With (Tightening Sequence) (6 Places)
      G09480573Courtesy of SUBARU OF AMERICA, INC.
    11. Install the bolt shown in the figure.
      NOTE: After tightening, if the liquid gasket is squeezed out in the seal surface area of the chain cover and oil pan upper, completely remove any liquid gasket that is squeezed out. Any liquid gasket on the chamfer area, however, should not be removed.

      Tightening torque: 

      25 N.m (2.5 kgf-m, 18.4 ft-lb)

    G09480557Courtesy of SUBARU OF AMERICA, INC.
  8. Set the part so that the installation surface of the oil pan upper is on the upper side.
  9. Check that the piston ring gap for each piston is positioned correctly. Refer to MECHANICAL (EXCEPT FOR STI)>CYLINDER BLOCK>ASSEMBLY>PISTON AND CONNECTING ROD .
  10. Install the piston and connecting rod to the cylinder block.
    1. Apply engine oil to the outer circumference of each piston, crankshaft pin, and in the cylinder block.
    2. Turn the crankshaft so that the #1 pin (A) of crankshaft is positioned at TDC using ST.

      ST 18252AA000 CRANKSHAFT SOCKET 

      G09480575Courtesy of SUBARU OF AMERICA, INC.
    3. Compress the piston ring using piston ring compressor, and insert the #1 connecting rod with #1 piston into cylinder block.
      CAUTION:
      • Be careful not to damage the cylinder liner and #1 pin of crankshaft by the #1 connecting rod large end.
      • Be careful not to apply strong impact when inserting to prevent connecting rod bearing from falling off.
      NOTE:
      • Face the piston front mark (round mark) towards the front of the engine.
        G13259309Courtesy of SUBARU OF AMERICA, INC.
      • Insert while lightly tapping the crown of the piston with the handle of a plastic hammer.
      G09480577Courtesy of SUBARU OF AMERICA, INC.
    4. Turn the crankshaft counterclockwise so that the #1 pin of crankshaft and the large end (A) of #1 connecting rod are positioned as shown in the figure using ST, while pressing the #1 piston crown, and then set the #1 connecting rod cap and #1 connecting rod cap bolt.
      NOTE:
      • Each connecting rod has its own mating cap. Make sure that they are assembled correctly by checking their matching symbol.
      • Use a new connecting rod cap bolt.
      • Apply a coat of engine oil to the #1 connecting rod cap seat and the connecting rod cap bolt threads.

      ST 18252AA000 CRANKSHAFT SOCKET 

      G09480578Courtesy of SUBARU OF AMERICA, INC.
    5. Using ST, tighten the #1 connecting rod cap bolts to 10 N.m (1.0 kgf-m, 7.4 ft-lb) in numerical order as shown in the figure, then retighten the bolts to 25 N.m (2.5 kgf-m, 18.4 ft-lb) in numerical order as shown in the figure.

      ST 18270AA020 SOCKET 

      G09480579Courtesy of SUBARU OF AMERICA, INC.
    6. Turn the crankshaft clockwise so that the #2 pin (A) of crankshaft is positioned at TDC using ST.

      ST 18252AA000 CRANKSHAFT SOCKET 

      G09480580Courtesy of SUBARU OF AMERICA, INC.
    7. Compress the piston ring using piston ring compressor, and insert the #2 connecting rod with #2 piston into cylinder block.
      CAUTION:
      • Be careful not to damage the cylinder liner and #2 pin of crankshaft by the #2 connecting rod large end.
      • Be careful not to apply strong impact when inserting to prevent connecting rod bearing from falling off.
      NOTE:
      • Face the piston front mark (round mark) towards the front of the engine.
        G13259314Courtesy of SUBARU OF AMERICA, INC.
      • Insert while lightly tapping the crown of the piston with the handle of a plastic hammer.
      G09480582Courtesy of SUBARU OF AMERICA, INC.
    8. Turn the crankshaft clockwise so that the #2 pin of crankshaft and the large end (A) of #2 connecting rod are positioned as shown in the figure using ST, while pressing the #2 piston crown, and then set the #2 connecting rod cap and #2 connecting rod cap bolt.
      NOTE:
      • Each connecting rod has its own mating cap. Make sure that they are assembled correctly by checking their matching symbol.
      • Use a new connecting rod cap bolt.
      • Apply a coat of engine oil to the #2 connecting rod cap seat and the connecting rod cap bolt threads.

      ST 18252AA000 CRANKSHAFT SOCKET 

      G09480583Courtesy of SUBARU OF AMERICA, INC.
    9. Using ST, tighten the #2 connecting rod cap bolts to 10 N.m (1.0 kgf-m, 7.4 ft-lb) in numerical order as shown in the figure, then retighten the bolts to 25 N.m (2.5 kgf-m, 18.4 ft-lb) in numerical order as shown in the figure.

      ST 18270AA020 SOCKET 

      G09480584Courtesy of SUBARU OF AMERICA, INC.
    10. Install #3 and #4 pistons and connecting rod caps in the same installation procedure as #1 and #2 pistons and connecting rod caps.
    11. Using ST and angle gauge, tighten the #1 connecting rod cap bolts and #4 connecting rod cap bolts with specified angle in numerical order as shown in the figure.

      ST 18270AA020 SOCKET 

      Tightening angle: 

      90°+5°-0°

      G09480585Courtesy of SUBARU OF AMERICA, INC.
    12. Turn the crankshaft so that the #2 connecting rod cap (A) and #3 connecting rod cap (B) is located at the position shown in the figure using ST.

      ST 18252AA000 CRANKSHAFT SOCKET 

      G09480586Courtesy of SUBARU OF AMERICA, INC.
    13. Using ST and angle gauge, tighten the #2 connecting rod cap bolts and #3 connecting rod cap bolts with specified angle in numerical order as shown in the figure.

      ST 18270AA020 SOCKET 

      Tightening angle: 

      90°+5°-0°

    G09480587Courtesy of SUBARU OF AMERICA, INC.
  11. Install the oil pan upper. Refer to LUBRICATION (EXCEPT FOR STI)>OIL PAN>INSTALLATION>OIL PAN UPPER .
  12. Set the part so that the installation surface of the intake manifold is on the upper side.
  13. Install the crankshaft position sensor with crankshaft position sensor holder to the cylinder block LH.

    Tightening torque: 

    6.4 N.m (0.7 kgf-m, 4.7 ft-lb)

    G09480544Courtesy of SUBARU OF AMERICA, INC.
  14. Install the PCV valve onto the cylinder block RH.
    NOTE: Apply liquid gasket to the bolt threads of PCV valve.

    Liquid gasket: 

    THREE BOND 1324 (Part No. 004403042) or equivalent

    Tightening torque: 

    23 N.m (2.3 kgf-m, 17.0 ft-lb)

    G09480543Courtesy of SUBARU OF AMERICA, INC.
  15. Install the knock sensor to the cylinder block LH.
    NOTE: Knock sensor must be positioned toward engine front so that the connector center position is within the range of shaded area shown in the figure.

    Tightening torque: 

    24 N.m (2.4 kgf-m, 17.7 ft-lb)

    G13259323Courtesy of SUBARU OF AMERICA, INC.
  16. Install the O-ring to the cylinder block and PCV connector.
    NOTE: Use new O-rings.
    G11267062Courtesy of SUBARU OF AMERICA, INC.
  17. Install the water pipe assembly and PCV connector to the cylinder block.

    Tightening torque: 

    6.4 N.m (0.7 kgf-m, 4.7 ft-lb)

    G11267061Courtesy of SUBARU OF AMERICA, INC.
  18. Install the engine rear hanger to the cylinder block RH.

    Tightening torque: 

    21 N.m (2.1 kgf-m, 15.5 ft-lb)

    G09480539Courtesy of SUBARU OF AMERICA, INC.
  19. Install the crank sprocket. Refer to MECHANICAL (EXCEPT FOR STI)>CRANK SPROCKET>INSTALLATION .
  20. Install the cylinder head. Refer to MECHANICAL (EXCEPT FOR STI)>CYLINDER HEAD>INSTALLATION .
  21. Apply a coat of engine oil to the oil seal inner periphery and outer periphery, and install the rear oil seal using ST1 and ST2.
    NOTE: Use a new rear oil seal.

    ST1 18671AA020 OIL SEAL GUIDE 

    ST2 18657AA030 OIL SEAL INSTALLER 

    G13259327Courtesy of SUBARU OF AMERICA, INC.
  22. Install the crankshaft position sensor plate with drive plate. (CVT model) Refer to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>DRIVE PLATE>INSTALLATION .
  23. Install the crankshaft position sensor plate with flywheel. (MT model) Refer to CLUTCH SYSTEM>FLYWHEEL>INSTALLATION .
  24. Install the clutch disc and cover. (MT model) Refer to CLUTCH SYSTEM>CLUTCH DISC AND COVER>INSTALLATION .
  25. Install the engine to the vehicle. Refer to MECHANICAL (EXCEPT FOR STI)>ENGINE ASSEMBLY>INSTALLATION .
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