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Valve Clearance Adjustment

NOTE: Adjust the valves only when the cylinder head temperature is less than 100°F (38°C).
  1. Remove the intake manifold (see REMOVAL ).
  2. Remove the cylinder head covers (see CYLINDER HEAD COVER REMOVAL  ).
  3. Set the No. 1 piston at top dead center (TDC). Align the pointer (A) on the front upper cover with the No. 1 piston TDC mark (B) on the front camshaft pulley.
    Fig 1: Identifying Pointer On Front Upper Cover With No. 1 Piston TDC Mark
    G05484616Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. Select the correct thickness feeler gauge for the valves you're going to check.

    Valve Clearance 

    Intake: 0.20-0.24 mm (0.008-0.009 in.) 

    Exhaust: 0.28-0.32 mm (0.011-0.013 in.) 

    REAR: 

    Fig 2: Identifying Intake And Exhaust Valves - Rear
    G05484617Courtesy of AMERICAN HONDA MOTOR CO., INC.

    FRONT: 

    Fig 3: Identifying Intake And Exhaust Valves - Front
    G05484618Courtesy of AMERICAN HONDA MOTOR CO., INC.
  5. Insert the feeler gauge (A) between the adjusting screw and the end of the valve stem on No. 1 cylinder and slide it back and forth; you should feel a slight amount of drag.
    Fig 4: Inserting Feeler Gauge Between Adjusting Screw And End Of Valve Stem
    G05484619Courtesy of AMERICAN HONDA MOTOR CO., INC.
  6. If you feel too much or too little drag, loosen the locknut (A), and turn the adjusting screw (B) until the drag on the feeler gauge is correct.
    Fig 5: Locknut And Adjusting Screw With Torque Specification
    G05484620Courtesy of AMERICAN HONDA MOTOR CO., INC.
  7. Tighten the locknut and recheck the clearance. Repeat the adjustment, if necessary.
  8. Rotate the crankshaft clockwise. Align the pointer (A) on the front upper cover with the No. 4 piston TDC mark (B) on the front camshaft pulley.
    Fig 6: Aligning Front Upper Cover Pointer With No. 4 Piston TDC Mark
    G05484621Courtesy of AMERICAN HONDA MOTOR CO., INC.
  9. Check and, if necessary, adjust the valve clearance on No. 4 cylinder.
  10. Rotate the crankshaft clockwise. Align the pointer (A) on the front upper cover with the No. 2 piston TDC mark (B) on the front camshaft pulley.
    Fig 7: Aligning Front Upper Cover Pointer With No. 2 Piston TDC Mark
    G05484622Courtesy of AMERICAN HONDA MOTOR CO., INC.
  11. Check and, if necessary, adjust the valve clearance on No. 2 cylinder.
  12. Rotate the crankshaft clockwise. Align the pointer (A) on the front upper cover with the No. 5 piston TDC mark (B) on the front camshaft pulley.
    Fig 8: Aligning Front Upper Cover Pointer With No. 5 Piston TDC Mark
    G05484623Courtesy of AMERICAN HONDA MOTOR CO., INC.
  13. Check and, if necessary, adjust the valve clearance on No. 5 cylinder.
  14. Rotate the crankshaft clockwise. Align the pointer (A) on the front upper cover with the No. 3 piston TDC mark (B) on the front camshaft pulley.
    Fig 9: Aligning Front Upper Cover Pointer With No. 3 Piston TDC Mark
    G05484624Courtesy of AMERICAN HONDA MOTOR CO., INC.
  15. Check and, if necessary, adjust the valve clearance on No. 3 cylinder.
  16. Rotate the crankshaft clockwise. Align the pointer (A) on the front upper cover with the No. 6 piston TDC mark (B) on the front camshaft pulley.
    Fig 10: Aligning Front Upper Cover Pointer With No. 6 Piston TDC Mark
    G05484625Courtesy of AMERICAN HONDA MOTOR CO., INC.
  17. Check and, if necessary, adjust the valve clearance on No. 6 cylinder.
  18. Install the cylinder head covers (see CYLINDER HEAD COVER INSTALLATION  ).
  19. Install the intake manifold (see INSTALLATION ).
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