QUANCHAI N485D, Руководство по обслуживанию

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ANHUI QUANCHAI ENGINE CO., LTD
4.10 detection for valve guide clearance
Check whether the valve guide is worn:
The maximum clearance between the intake
valve stem and the guide hole is 0.13 mm, while
that between the exhaust valve stem and the
guide hole is 0.15 mm. If the clearance exceeds
the limit after a new valve is installed, a new
valve guide must be installed.
It is recommended to check the valve guide
clearance as follows:
1) Put a new valve into the new valve guide.
2) Place the dial gauge with the magnetic base on
the surface of the cylinder head.
3) Lift the valve for 15 mm, make the gauge
contact the edge of the valve head, and put the
valve radially away from the gauge. When the
valve is held at this position, zero the dial gauge.
4) Put the valve radially across the cylinder head
axis and toward the gauge. Record the gauge
reading. If the measured data is equal to or
greater than the following data, a new valve
guide must be installed.
The maximum allowable clearance is as follows
when the valve is lifted for 15 mm:
Intake valve guide: 0.24 mm
Exhaust valve guide: 0.32 mm
A - Dial gauge
B - Gauge
C - Valve head
D - Valve guide
E - Maximum clearance between the valve stem
and the guide hole
A
B
C
D
E