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Piston And Connecting Rod

WARNING: This page is about a different variant/trim than selected.
G13642023Courtesy 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 cut-out portion of circlip groove (b) do not match.
    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.
    G13642025Courtesy 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 cut-out portion of circlip groove (b) do not match.
    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.
    G13642029Courtesy of SUBARU OF AMERICA, INC.
    1. Set the ring gap of the expander to the position (A).
      G09480613Courtesy of SUBARU OF AMERICA, INC.
    2. Set the lower rail spin stopper (D) to the oil groove (C) located above the cut-out portion (B) of the piston skirt coating, and hook the lower rail spin stopper (F) to the expander (E).
      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).
    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.
      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.
    G09480617Courtesy of SUBARU OF AMERICA, INC.
  8. Check that the piston ring is installed correctly.
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