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Valve Clearance: Adjustment

WARNING: This page is about a different car, the 2012 Nissan Pathfinder. However, it is still accessible from the selected car via links, so may be relevant.
  1. Measure the valve clearance.
  2. Remove camshaft. Refer to "REMOVAL AND INSTALLATION ".
  3. Remove valve lifters at the locations that are out of the standard.
  4. Measure the center thickness of removed valve lifters with micrometer.
    Fig 1: Measuring Center Thickness Of Valve Lifters Using Micrometer
    G04878398Courtesy of NISSAN NORTH AMERICA, INC.
  5. Use the equation below to calculate valve lifter thickness for replacement.

    Valve lifter thickness calculation: t = t1+ (C1-C2) 

    t = Valve lifter thickness to be replaced 

    t1 = Removed valve lifter thickness 

    C1 = Measured valve clearance 

    C2 = Standard valve clearance: 

    Intake: 0.26 - 0.34 mm (0.010 - 0.013 in)* 

    Exhaust: 0.29 - 0.37 mm (0.011 - 0.015 in)* 

    *: Approximately 20°C (68°F) 

    • Thickness of new valve lifter can be identified by stamp marks on the reverse side (inside the cylinder).
      Fig 2: Identifying Stamp Marks And Thickness Of Valve Lifter
      G04878399Courtesy of NISSAN NORTH AMERICA, INC.
    INTAKE VALVE THICKNESS SPECIFICATIONS

    Stamp mark Thickness
    788U 7.88 mm (0.3102 in)
    790U 7.90 mm (0.3110 in)
    . .
    . .
    840U 8.40 mm (0.3307 in)

    Available thickness of valve lifter: 27 sizes with range 7.88 to 8.40 mm (0.3102 to 0.3307 in) in steps of 0.02 mm (0.0008 in) (when manufactured at factory). Refer to "STANDARD AND LIMIT ".

    EXHAUST VALVE THICKNESS SPECIFICATIONS

    Stamp mark Thickness
    N788 7.88 mm (0.3102 in)
    N790 7.90 mm (0.3110 in)
    . .
    . .
    N836 8.36 mm (0.3291 in)

    Available thickness of valve lifter: 25 sizes with range 7.88 to 8.36 mm (0.3102 to 0.3291 in) in steps of 0.02 mm (0.0008 in) (when manufactured at factory). Refer to "STANDARD AND LIMIT ".

    CAUTION: Install identification letter at the end and top, "U" and "N", at each of proper positions. (Be careful of mis-installation between intake and exhaust.)
  6. Install selected valve lifter.
  7. Install camshaft. Refer to "REMOVAL AND INSTALLATION ".
  8. Manually turn crankshaft pulley a few turns.
  9. Make sure that the valve clearances for cold engine are within the specifications by referring to the specified values.
  10. Installation of the remaining components is in the reverse order of removal.
  11. Start the engine, and check for unusual noise and vibration.