Valve Clearance Adjustment
Measure valve clearance as described in the following procedure.
Check and adjust the valve clearance with the timing chain installed.
CAUTION:
Always rotate the crankshaft clockwise.
- 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.)
- Valve clearance can be measured at the illustrated location in this condition.
- Use a thickness 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 ± 0.001 inch)
Exhaust side: 0.30 ± 0.03 mm (0.012 ± 0.001 inch)
- If measured values are out of the standard value, record measured values.
- 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.
- Valve clearance can be measured at the illustrated location in this condition.
- If measured values are out of the standard value, record measured values.
- 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 (0.1181 inch) and 3.690 mm (0.1453 inch).
- Use the following procedure select a valve tappet.
- Measure thickness of a removed valve tappet.
- 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 [0.008 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.