Valve Clearance: Adjustments

Valve Clearance

1. Start the engine and allow it to warm up until the engine coolant temperature reaches 80 to 95°C (176 to 203°F).
2. Remove all spark plugs from the cylinder head for easy inspection.
3. Remove the rocker cover.

Timing Indicator:

4. Turn the crankshaft clockwise until the notch on the pulley is lined up with the "T" mark on the timing indicator.

Determining TDC:

5. Move the rocker arms on the No.1 and No.4 cylinders up and down by hand to determine which cylinder has its piston at the top dead center on the compression stroke.

Note: If both intake and exhaust valve rocker arms have a valve lash, the piston in the cylinder corresponding to these rocker arms is at the top dead center on the compression stroke.

Valve Clearance:

6. Valve clearance inspection and adjustment can be performed on rocker arms indicated by white arrows (as shown on image for No.1 & No.3) when the No.1 cylinder piston is at the top dead center on the compression stroke, and on rocker arms indicated by solid arrows (as shown on image for No.2 & No.4) when the No. 4 cylinder piston is at the top dead center on the compression stroke.
7. Measure the valve clearance.
If the valve clearance is not as specified, loosen the rocker arm lock nut and adjust the clearance using a feeler gauge while turning the adjusting screw.
Standard value (hot engine):
Intake valve 0.20 mm (0.008 in.)
Exhaust valve 0.30 mm (0.012 in.)

Lock Nut:

8. While holding the adjusting screw with a screwdriver to prevent it from turning, tighten the lock nut to the specified torque.
Tightening torque: 9 Nm (7 ft.lbs.)
9. Turn the crankshaft through 36O° to line up the notch on the crankshaft pulley with the "T" mark on the timing indicator.
1O Repeat steps (7) and (8) on other valves for clearance adjustment.
11. Install the rocker cover.
12. Install the spark plugs and tighten to the specified torque.
Tightening torque: 25 Nm (18 ft.lbs.).