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Note: Replace the foam element (d) if it is deformed or broken
6.2.3- Spark Plug
Recommended spark plug: F7TC or equivalent
To ensure proper engine operation, the spark plug must be properly gapped and free of deposits.
1. Remove the spark plug.
WARNING! The muffler becomes very hot during operation and remains hot for a while after
stopping the engine. Be careful not to touch the muffler while it is hot.
ATTENTION: never touch the spark plug immediately after the engine is stopped to avoid getting
burnt by the high temperature.
Remark: Too much suction of the fuel or using wasted or regenerated oil can pollute the spark plug
electrode and make it hard to start the engine.
2. Visually inspect the spark plug. Discard it if the insulator is cracked or
chipped.
Clean the spark plug with a wire brush if it is to be reused or fit a new one.
3. Measure the plug gap with a feeler gauge.
Correct as necessary by bending the side electrode.
The gap should be: 0.70-0.80mm (0.028-0.031 in)
4. Check that the spark plug washer is in good condition, and thread the spark
plug in by hand to prevent cross-threading.
Fig.23
5. After the spark plug is seated, tighten with a spark plug wrench to compress the washer.
- If installing a new spark plug, tighten 1/2 turn after spark plug seats to compress the washer.
- If reinstalling a used spark plug, tighten 1/8-1/2 turn after the spark plug seats to compress the
washer.
NOTICE:
● The spark plug must be securely tightened. An improperly tightened spark plug can become very
hot and may cause engine damage.
● Use only the recommended spark plug or equivalent. A spark plug which has an improper heat
range may cause engine damage.
6.2.4- Fuel system cleaning
a) Sediment cup cleaning
Move the fuel valve to the OFF position and then remove
the fuel sediment cup and O-ring.
Wash the sediment cup and O-ring in nonflammable
solvent and dry them thoroughly.
Place the O-ring in the sediment cup and then install and
tighten the sediment cup securely.
Move the fuel valve to the ON position, and check for
leaks. Replace the O-ring if there is any leakage.
Fig.24
b) Fuel tank cap & filter
Remove the fuel tank cap and filter.
Wash the filter in nonflammable solvent and dry it thoroughly.
Replace filter and cap
