Zontes ZT310M 2022, Руководство по обслуживанию

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• The cylinder head gasket is damaged.
4. The engine is electrically started, and the crankshaft rotates without cylinder pressure or
the cylinder pressure is very small.
• The valve spring is broken.
• Broken valve.
• Blow-by of cylinder block and cylinder head gasket.
• The spark plug is loose and leaking.
• Excessive carbon deposits on the valve.Causes valves to close poorly.
Four, Cylinder compression test
1. Warm up the engine to normal operating temperature, stop the machine and pull out the spark plug cap and remove
the spark plug
(Refer to ZT310T-M maintenance manual-2.Maintenance-Spark plug for disassembly and
assembly).
2. Install the cylinder pressure gauge connector into the spark plug hole.
3. Fully open the throttle opening, press the start switch, and use the starter motor to drive the crankshaft and piston
to run until the cylinder pressure gauge stops rising (S
tarter motor running time ≤ 15s).
Engine speed: 480-525r/min
Compression pressure: 750-1050 KPa (7.65- 10.71 Kgf/cm2, 108.8-152.3 psi)
①
If the measured cylinder pressure is higher than the normal value, it indicates that there is carbon deposit on the
top of the piston or on the cylinder wall.
②
If the measured cylinder pressure is lower than the normal value, pour a small amount of clean oil from the spark
plug, rotate the crankshaft a few times, make the piston ring and cylinder wall evenly covered with oil film, and retest
the cylinder pressure. If the cylinder pressure measured after the oil is poured is greater than the last cylinder
pressure value, please disassemble the machine and check the piston and piston ring.
Failure analysis:
a. The piston ring is worn.
b. Cylinder wear.
③
If the cylinder pressure measured by pouring oil is the same as the last time (The cylinder pressure is too small),
First measure the valve clearance of the intake and exhaust valves for any abnormalities, then dismantle the machine
to check the intake and exhaust valves for leaks and the cylinder head gasket coating for damage to the blowby gas.
Five, Cylinder head cover
Cylinder head cover removal
1. As shown in the figure, use scissors to cut off the separator fixing tie, use clamp pliers to remove the separator tube
clamp, and remove the separator.