Valve Clearance: Adjustments

Fig. 21 Valve Shim Thickness Chart.:

The valves are adjusted by use of an adjusting shim.
1. With No. 1 piston at TDC on compression stroke, and measure and record clearance between valve lifter and camshaft:
No. 1 Intake & Exhaust
No. 2 Intake
No. 3 Exhaust
2. Turn crankshaft in normal direction of rotation one full revolution (360°) and measure and record clearance between valve lifter and camshaft:
No. 2 Exhaust
No. 3 Intake
No. 4 Intake and Exhaust
3. Turn crankshaft to position camshaft cam lobe on adjusting valve upward.
4. Position valve lifter notch, then using suitable small screwdriver, remove adjusting shim.
5. Using suitable micrometer, measure thickness of removed shim.
6. New shim thickness equals measured valve clearance less .006-.010 inch on intake valves or .012-.016 inch on exhaust valves, plus thickness of used shim.
7. Select new shim with thickness as close as possible to values calculated in step 6, Fig. 21.
8. Install new shim, then recheck valve clearance.