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Piston And Connecting Rod

WARNING: This page is about a different variant/trim than selected.
Fig 1: Identifying Piston And Connecting Rod Components
G10292099Courtesy of SUBARU OF AMERICA, INC.
  1. Install the connecting rod bearing to the connecting rod and connecting rod cap.
  2. Install the circlip on one end of the piston using a flat tip screwdriver.
    NOTE:
    • Be careful not damage the piston, by wrapping the tip of flat tip screwdriver with tape.
    • Make sure the circlip is firmly inserted into the circlip groove.
    • After installing the circlip, rotate the circlip so that its end part (a) and the cutout portion of circlip groove (b) do not match.
    Fig 2: Identifying Circlip End Part And Groove
    G09480609Courtesy of SUBARU OF AMERICA, INC.
  3. Set the piston to the connecting rod.
    NOTE: Align the front mark of piston and the connecting rod direction correctly as shown in the figure.
    Fig 3: Aligning Piston And Connecting Rod Front Marks
    G10292101Courtesy of SUBARU OF AMERICA, INC.
  4. Apply engine oil to the piston pin, and attach the piston pin.
  5. Install the circlip on the piston using a flat tip screwdriver.
    NOTE:
    • Be careful not damage the piston and piston pin, by wrapping the tip of flat tip screwdriver with tape.
    • Make sure the circlip is firmly inserted into the circlip groove.
    • After installing the circlip, rotate the circlip so that its end part (a) and the cutout portion of circlip groove (b) do not match.
    Fig 4: Identifying Circlip End Part And Groove
    G09480611Courtesy of SUBARU OF AMERICA, INC.
  6. Install the oil rings to the piston in the order of expander, lower rail and upper rail by hand.
    NOTE: Oil ring consists of the upper rail, expander and lower rail.
    Fig 5: Identifying Oil Ring Upper Rail, Expander And Lower Rail
    G10292103Courtesy of SUBARU OF AMERICA, INC.
    1. Set the ring gap of the expander to the position (A).
      Fig 6: Identifying Expander Ring Gap Positions
      G09480613Courtesy of SUBARU OF AMERICA, INC.
    2. Set the lower rail spin stopper (D) to the oil groove (C) located above the cutout portion (B) of the piston skirt coating, and hook the lower rail spin stopper (F) to the expander (E).
      Fig 7: Identifying Expander Lower Rail Spin Stopper And Oil Groove
      G09480614Courtesy of SUBARU OF AMERICA, INC.
    3. Set the upper rail gap to the position (G), and hook the upper rail spin stopper (H) to the expander (E).
      Fig 8: Identifying Expander Upper Rail Spin Stopper And Gap Position
      G09480615Courtesy of SUBARU OF AMERICA, INC.
  7. Install the compression rings to the piston in the order of second ring and top ring, using piston ring expander.
    1. Set the ring gap of the second ring to the position (A) in the figure.
      NOTE: Install the second ring so that the ring mark (2N) faces the piston crown.
      Fig 9: Identifying Piston Crown Ring Marks
      G09480616Courtesy of SUBARU OF AMERICA, INC.
    2. Set the ring gap of top ring at (B) in the figure on the 180° opposite direction of (A).
      NOTE: Install the top ring so that the ring mark (TN) faces the piston crown.
      Fig 10: Identifying Piston Crown Ring Mark (TN)
      G09480617Courtesy of SUBARU OF AMERICA, INC.
  8. Check that the piston ring is installed correctly.