Honda GX690 Workshop Manual page 41

Insert a thickness gauge between the valve rocker arm
(1) and valve stem (2) to measure the valve clearance.
VALVE CLEARANCE:
IN: 0.08 ± 0.02 mm
EX: 0.10 ± 0.02 mm
Set the piston of the No.2 cylinder at the top dead
center of the cylinder compression stroke (both valves
fully closed) by rotating the flywheel (1) 270 degrees
clockwise slowly. When the No.2 piston is at the top
dead center of the compression stroke, the "T" mark (2)
on the cooling fan will align with the left side alignment
mark (3) on the fan cover.
Insert a thickness gauge between the valve rocker arm
and valve stem to measure the valve clearance.
VALVE CLEARANCE:
IN: 0.08 ± 0.02 mm
EX: 0.10 ± 0.02 mm
If adjustment is necessary, proceed as follows.
Hold the tappet adjusting screw (1) and loosen the
tappet adjusting nut (2).
TOOL:
Tappet adjusting wrench 3 mm (3) 07708-0030400
Turn the tappet adjusting screw to obtain the specified
clearance.
VALVE CLEARANCE:
IN: 0.08 ± 0.02 mm
EX: 0.10 ± 0.02 mm
Hold the tappet adjusting screw and retighten the
tappet adjusting nut to the specified torque.
TORQUE: 7.5 N·m (0.75 kgf·m, 5.5 lbf·ft)
Recheck the valve clearance, and if necessary, readjust
the clearance.
Check the valve cover packing for damage or
deterioration and install it on the valve cover.
Attach the cylinder valve cover to the cylinder and
tighten the flange bolts securely.
(1)
(3)
(2)
(3)
(1)
To decrease valve clearance: screw in.
To increase valve clearance: screw out.
(2)
MAINTENANCE
(2)
(1)
270°
(1)
(2)
3-9