Tappet clearance: this is the clearance available between the rocker arm tip and valve stem when the valves are closed position when engine at cooled condition, i.e. at the compression stroke
How to adjust tappet clearance?
- Prepare the following exclusive tools:
- Feeler gauge 0.4 mm thick for suction valve
- Feeler gauge 0.5 mm thick for exhaust valve.(depending on your engine,may be different for different engines)
FIG.: Valve Head Clearance Adjusting Procedure
- Turn the flywheel to bring the cylinder for which the clearance is to be adjusted to assume the T.D.C. of the compression stroke.
- Loosen the lock nuts 2 & 4 , and then loosen the rocker arm adjusting screw 1 and valve guard adjusting screw 3 .
- Press down the center of the valve guard from above (so that the clearance becomes zero under this condition). Gradually tighten the valve guard adjusting screw 3 so that the clearance becomes zero. After the adjustment, lock the adjusting screw 3 not to turn, and securely tighten the lock nut 4 .
- Put a feeler gauge into a clearance between the rocker arm adjusting screw1 and the valve guard, and gradually tighten the rocker arm adjusting screw 1 until the clearance becomes narrow enough to permit the feeler gauge to be smoothly drawn out. Then, lock the adjusting screw 1 , and tighten the lock nut 2 .
- After having securely tightened the lock nut 2 , check that the feeler gauge can be smoothly drawn out