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Valve Clearance: Adjustment

WARNING: This page is about a different variant/trim than selected.
  1. Remove the engine from the vehicle. Refer to MECHANICAL(STI)>ENGINE ASSEMBLY>REMOVAL .
  2. Measure all the valve clearances.
    1. Remove the timing belt cover RH. Refer to MECHANICAL(STI)>TIMING BELT COVER>REMOVAL .
    2. Disconnect the connector (A) from the exhaust camshaft position sensor and the connector (B) from the exhaust oil flow control solenoid valve LH.
    3. Remove the clip (C) holding the engine harness.
      G12437712Courtesy of SUBARU OF AMERICA, INC.
    4. Remove the clip (A) which hold the engine harness to the rocker cover RH.
      G08539331Courtesy of SUBARU OF AMERICA, INC.
    5. Remove the air duct B (B) from the rocker cover LH and the air duct A (A).
      G08539168Courtesy of SUBARU OF AMERICA, INC.
    6. Remove the ignition coil. Refer to IGNITION(STI)>IGNITION COIL>REMOVAL .
    7. Unlock the leak diagnosis connector, and disconnect the vacuum hose (A).
    8. Remove the leak diagnosis connector (C) from the PCV hose (B).
      G12437715Courtesy of SUBARU OF AMERICA, INC.
    9. Unlock the leak diagnosis connector, and disconnect the vacuum hose.
      G12437716Courtesy of SUBARU OF AMERICA, INC.
    10. Remove the rocker cover.
    11. Turn the crank pulley clockwise until the round mark on the camshaft sprocket is set to position shown in the figure.
      NOTE: Turn the crank pulley using a socket wrench.
      • Measurement of clearance of #1 cylinder intake valve and #3 cylinder exhaust valve
        G06345045Courtesy of SUBARU OF AMERICA, INC.
      • Measurement of clearance of #2 cylinder exhaust valve and #3 cylinder intake valve
        G06345046Courtesy of SUBARU OF AMERICA, INC.
      • Measurement of clearance of #2 cylinder intake valve and #4 cylinder exhaust valve
        G06345047Courtesy of SUBARU OF AMERICA, INC.
      • Measurement of clearance of #1 cylinder exhaust valve and #4 cylinder intake valve
      G06345048Courtesy of SUBARU OF AMERICA, INC.
    12. Measure the clearance of intake valve and exhaust valve using thickness gauge (A).
      NOTE:
      • Insert a thickness gauge in a direction as horizontal as possible with respect to the valve lifter.
      • Record the measured value of each valve clearance.
      G08539175Courtesy of SUBARU OF AMERICA, INC.
  3. Remove the camshaft. Refer to MECHANICAL(STI)>CAMSHAFT>REMOVAL .
  4. Remove the valve lifter.
  5. Measure the thickness of valve lifter using micrometer.
    G04998619Courtesy of SUBARU OF AMERICA, INC.
  6. Select a valve lifter of suitable thickness using the measured valve clearance and valve lifter thickness, and install it.
    NOTE: Use a new valve lifter.
    Unit: mm (in) 
    Intake valve: S = (V + T) - 0.19 (0.0075)
    Exhaust valve: S = (V + T) - 0.35 (0.0138)
    S: Valve lifter thickness required
    V: Measured valve clearance
    T: Current valve lifter thickness
  7. Install the camshaft. Refer to MECHANICAL(STI)>CAMSHAFT>INSTALLATION .
  8. Install the cam sprocket. Refer to MECHANICAL(STI)>CAM SPROCKET>INSTALLATION .
  9. Install the timing belt. Refer to MECHANICAL(STI)>TIMING BELT>INSTALLATION>TIMING BELT .
  10. Measure all valves for valve clearance again at this time. If the valve clearance is not within the adjustment value, repeat the procedure over again from step  3.

    Valve clearance (adjustment value): 

    Intake 

    0.20+0.01-0.03 mm (0.0079+0.0004-0.0012 in)

    Exhaust 

    0.35±0.02 mm (0.0138±0.0008 in)

  11. After adjustment, install the related parts in the reverse order of removal.
    NOTE: Refer to "Camshaft" when installing the related parts. Refer to MECHANICAL(STI)>CAMSHAFT>INSTALLATION .
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