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Spark plug
System components
Remove the spark plug
1. Use the special spark plug socket -16# or the extended socket head -16# to remove the spark plug counterclockwise.
Check spark plugs
1. Check the thread of the spark plug and the center electrode. If there is any damage or deformation, replace the spark plug.
2. Use a feeler gauge to measure the gap a of the spark plug, if it exceeds the range, replace the spark plug.
Note: the standard value of spark plug gap is 0.7-0.9mm.
Install spark plugs
1. Screw the spark plug into the cylinder head, put on the spark plug special sleeve -16# or the extended sleeve head -16#, and
pre-tighten it with a torque wrench to fix the torque, the torque is 14±1 N.m.
Cylinder compression test
1. Start the engine, warm up the engine to normal operating temperature, and then turn off the engine.
2. Remove the dust near the spark plug and remove the spark plug.
3. Install the cylinder pressure gauge.
4. Fully open the throttle, press the start switch, and use the starter motor to drive the crankshaft and piston to run until the
cylinder pressure gauge reading stops rising (starter motor running time ≤ 15s).
Engine speed: 420-510r/min
Compression pressure:
440-550kpa (4.49-5.61 kgf/cm
2
, 63.8-79.8 psi)
① if the measured cylinder pressure is larger than the
normal value, it means that there is carbon deposit on the top of the
piston or the wall of the cylinder.
spark plug
a
