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21
Adjustment of the valve clearance
Technique demand (cold state)
Intake valve clearance: 0.4±0.05mm;
Exhaust valve clearance: 0.45±0.05mm
To determine the compression TDC of the first cylinder: Rotate the crankshaft to
make the TDC indicator, which is mounted on the gear house cover, point to the “0”
position on the belt pulley damper. Then go on rotating in a small range of angles
(10°~20°) clockwise and counterclockwise. When the intake and exhaust rockers of the
first cylinder do not swing but those of the forth cylinder swing, rotate the crankshaft
back to make the indicator point to the “o” position. At this time, the piston of the first
cylinder is on the compression TDC. If counter, that indicates the forth piston is on the
compression TDC. The first piston can reach the compression TDC by rotating the
crankshaft 360°
Figure 10 Fuel injection pressure
adjustments
To adjust valve clearance: Rotate the
crankshaft to the position that the first piston
is on the compression TDC, when the No.1,2,3
and 6 valves can be adjusted; and then rotate
the crankshaft 360°, when the No. 4, 5, 7 and 8
valves can be adjusted. First, loose the
tightening nut of the adjustment bolt and
screw the adjustment bolt out to the suitable
position. Then put the feeler gauge into the
gap between rocker and the end of valve stem.
Next screw in the adjustment bolt till rocker can fasten the feeler gauge. Finally, tighten