Valve Clearance Adjustment
VALVE CLEARANCE ADJUSTMENTMeasure valve clearance in the following procedure.
CAUTION:
Always rotate the crankshaft clockwise.
1. Rotate the crankshaft clockwise to align the timing mark of the V.V.T. sprocket with the top surface of the cylinder head as illustrated. (Set the Number 1 piston at top dead center on the compression stroke.)
2. Valve clearance can be measured at the illustrated location in this condition.
3. Use a free gauge to measure clearance between the camshaft and valve tappet.
Standard value (when engine is cold):
Intake side: 0.20 ± 0.03 mm (0.008 ± 0.001inch)
Exhaust side: 0.30 ± 0.03 mm (0.012 ± 0.001 inch)
4. If measured values are out of the standard value, record measured values.
5. Rotate the crankshaft by one turn clockwise to set the Number 4 piston at top dead center on the compression stroke.
NOTE: The timing mark of the V.V.T. exhaust sprocket must be at the illustrated position.
6. Valve clearance can be measured at the illustrated location in this condition.
7. If measured values are out of the standard value, record measured values.
8. If the measured value is out of the standard value, replace the valve tappet.
NOTE: There are 47 kinds of valve tappets at intervals of 0.015 mm (0.0006 inch) in the range between 3.000 mm (0.1181 inch) and 3.690 mm (0.145 inch).
9. Select a valve tappet in the following procedure.
1) Measure thickness of a removed valve tappet.
2) Calculate thickness of a valve tappet so that valve clearance meets the standard value.
A: Thickness of valve tappet to be selected
B: Thickness of removed valve tappet
C: Measured valve clearance
Formula
Intake side: A = B + (C - 0.20 mm [0.08 inch])
Exhaust side: A = B + (C - 0.30 mm [0.012 inch])
Refer to "Removal and installation of camshaft" for removal, installation and inspection procedure of valve tappets.