Yanmar 3JH4E Service Manual page 36

2. Inspection and Adjustment
c) Valve clearance measurement
Insert a thickness gage between the rocker arm
and valve cap, and record the measured valve
clearance.
(Use it as the data for estimating the wear state.)
d) Adjusting other cylinders
Turn the crankshaft 240
for the No.3 cylinder.
cylinder in this order.
The cylinder to be adjusted first does not have to
be the No.1 cylinder.
cylinder where the piston is the nearest to the top
dead center after turning, and make adjustment for other cylinders in the order of ignition by
turning the crankshaft 240
The adjustment method of reducing the flywheel turning numbers (for reference):
Set NO.1 cylinder to the compression T.D.C. and adjust the clearance of the
table. Next, turn the flywheel once (the suction/ exhaust valve of NO.1 cylinder is in the position of
the overlap T.D.C. at this time), and adjust the clearance of the
Ignition order of 3 cylinder engines: 1
Cylinder No.
Valve
No.1 compression
T.D.C
No.1 overlap T.D.C
2) Valve clearance inspection and adjustment
a) Loosen adjusting bolts
Loosen the lock nut and adjust the screw. And
check the valve for any inclination of valve cap,
entrance of dirt or wear.
b) Measure valve clearance
Insert a 0.2 mm thickness gage between the
rocker arm and valve cap, and adjust the valve
clearance. Tighten the adjusting bolt.
Standard valve clearance (mm)
0.15-0.25
c) Apply oil to the contact surface between
adjusting screw and push rod.
d) Adjusting other cylinders
Turn the crankshaft 240
adjustment for the No.3 cylinder. Then adjust the
No.2 cylinder in this order.
The cylinder to be adjusted first does not have to
be the No.1 cylinder.
cylinder where the piston is the nearest to the top dead center after turning, and make adjustment
for other cylinders in the order of ignition by turning the crankshaft 240
and make adjustment
°
Then adjust the No.2
Select and adjust the
ach time.
° e
→
1
Suction Exhaust Suction
° then and make
Select and adjust the
Valve
clearance
→
3 2
2
Exhaust Suction
(Normal)
(Valve clearance adjustment)
20
Rocker arm
Adjusting screw
(Valve clearance)
mark of the below
mark.
3
Exhaust
The first time
The second time
Valve cap
(Abnormal)
each time.
°
Lock nut