Valve Clearance: Adjusting

Adjust valve clearance while engine is cold. 

1. Turn crankshaft. Position cam lobe upward on camshaft for valve that must be adjusted.
2. Place Tool (1) around camshaft as shown in Fig 1.

   Before placing Tool (1), rotate notch toward center of cylinder head. (See  Fig 1 .) This will simplify shim removal later. 

   CAUTION: Be careful not to damage cam surface with Tool (1).
   Fig 1: Placing Tool Around Camshaft

   Courtesy of NISSAN MOTOR CO., U.S.A.
3. Rotate Tool (1) so that valve lifter is pushed down.
   Fig 2: Rotating Camshaft

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CAUTION:
• Tool (2) must be placed as close to camshaft bracket as possible.
  Fig 3: Retaining Valve Lifter Position

  Courtesy of NISSAN MOTOR CO., U.S.A.
• Be careful not to damage cam surface with Tool (2).
4. Place Tool (2) between camshaft and valve lifter to retain valve lifter.
5. Remove Tool (1).
6. Remove adjusting shim using a small screwdriver and a magnetic finger.
   Fig 4: Removing Adjusting Shim

   Courtesy of NISSAN MOTOR CO., U.S.A.
   Fig 5: Measuring Shim Thickness

   Courtesy of NISSAN MOTOR CO., U.S.A.
7. Determine replacement adjusting shim size using the following formula.
   Fig 6: Calculating Thickness Of Replacement Shim

   Courtesy of NISSAN MOTOR CO., U.S.A.
   • Use a micrometer to determine thickness of removed shim.
   • Calculate thickness of new adjusting shim so valve clearance comes within specified values.

     R = Thickness of removed shim

     N = Thickness of new shim

     M = Measured valve clearance

     Intake: N = R + [M - 0.37 mm (0.0146 in)] 

     Exhaust: N = R + [M - 0.40 mm (0.0157 in)] 

     Shims are available in 50 sizes from 2.00 mm (0.0787 in) to 2.98 mm (0.1173 in), in steps of 0.02 mm (0.0008 in). 

   • Select the closest size shim to the calculated thickness. Refer to AVAILABLE SHIMS .
8. Install new shim using a suitable tool.
   • Install with the surface on which the thickness is stamped facing down. 
     Fig 7: Installing Shim

     Courtesy of NISSAN MOTOR CO., U.S.A.
9. Place Tool (1) as explained in steps  2 and  3.
10. Remove Tool (2).
11. Remove Tool (1).
12. Recheck the valve clearance.
    Fig 8: Valve Clearance Table

    Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 9: Identifying Placement Of Tools

    Courtesy of NISSAN MOTOR CO., U.S.A.

    Whenever valve clearances are adjusted to cold specifications, check that the clearances satisfy hot specifications and adjust again if necessary.