HONDA GX390 - Manual (Page 12)

ENGLISH
SEDIMENT CUP
Cleaning
SPARK PLUG
Recommended Spark Plugs:
SPARK PLUG WRENCH
SEALING
WASHER
SIDE ELECTRODE
O-RING
SEDIMENT CUP
FUEL VALVE LEVER
OFF
0.7 0.8 mm
(0.028 0.031 in)
12
BPR6ES (NGK)
W20EPR-U (DENSO)
The recommended spark plug has the correct heat range for
normal engine operating temperatures.
An incorrect spark plug can cause engine damage.
Gasoline is highly flammable and explosive, and you
can be burned or seriously injured when handling
fuel.
Attach the spark plug cap to the spark plug.
A loose spark plug can overheat and damage the engine.
Overtightening the spark plug can damage the threads in the
cylinder head.
When reinstalling the original spark plug, tighten 1/8 1/4 turn
after the spark plug seats to compress the washer.
When installing a new spark plug, tighten 1/2 turn after the spark
plug seats to compress the washer.
After the spark plug is seated, tighten with a 13/16-inch spark
plug wrench to compress the sealing washer.
Install the spark plug carefully,
by hand, to avoid cross-
threading.
The gap should be:
Measure the spark plug
electrode gap with a wire-
type feeler gauge. Correct the
gap, if necessary, by carefully
bending the side electrode.
Visually inspect the spark
plug. Replace it if damaged or
badly fouled, if the sealing
washer is in poor condition,
or if the electrode is worn.
Remove the spark plug with a
13/16-inch spark plug wrench.
Disconnect the spark plug cap,
and remove any dirt from
around the spark plug area.
For good performance, the spark plug must be properly gapped
and free of deposits.
If the engine has been running, let to cool before servicing the
spark plug.
0.7 0.8 mm (0.028 0.031 in)
Move the fuel valve to the ON position, and check for leaks.
Replace the O-ring if there is any leakage.
Place the O-ring in the fuel valve, and install the sediment cup.
Tighten the sediment cup securely.
Wash the sediment cup in non-flammable solvent, and dry it
thoroughly.
Move the fuel valve to the OFF position, then remove the fuel
sediment cup and O-ring.
Wipe up spills immediately.
Handle fuel only outdoors.
Stop engine and keep heat, sparks, and flame away.
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