Valve Clearance: Adjustments

Adjust valve clearance while engine is cold.
1. Turn the crankshaft to position cam lobe on camshaft of the valve that must be adjusted upward.
2. Place camshaft pliers, tool No. J38972-1 (A), around camshaft as shown in figure.
3. Rotate camshaft pliers so that lifter is pushed down.

NOTE: Before using camshaft pliers, rotate notch toward center of cylinder head (see figure). This will simplify shim removal later.

CAUTION: Be careful not to damage cam surface with tools.





4. Place lifter stopper, tool No. J38972-2 (B), between camshaft and valve lifter to retain valve lifter.

NOTE: Lifter stopper tool must be placed as close to camshaft bracket as possible. Be careful not to damage cam surface with tool.

5. Remove camshaft pliers.





6. Remove adjusting shim using a small screwdriver and a magnetic finger.
7. Determine replacement adjusting shim size as follows:
a. Using a micrometer, determine thickness of removed shim.





b. Calculate the thickness of new adjusting shim so the valve clearance comes within the specified values.
R = Thickness of removed shim
N = Thickness of new shim
M = Measured valve clearance
Intake and exhaust: N = R + [M - 0.37 mm (0.0146 inch)]





NOTE: Shims are available in thicknesses from 1.96 mm (0.0772 inch) to 2.68 mm (0.1055 inch), in increments of 0.02 mm (0.0008 inch).

c. Select new shim with thickness as close as possible to calculated value.
8. Install new shim using a suitable tool.





NOTE: Install with the surface on which the thickness is stamped facing down.





9. Place camshaft pliers as mentioned in steps 2 and 3.
10. Remove the tools.
11. Recheck valve clearance.