Honda GX670 User Manual

SERVICING YOUR HONDA ENGINE
SPARK PLUG SERVICE
Recommended spark plugs: ZGR5A (NGK)
J16CR-U (DENSO)
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Incorrect spark plugs can cause engine damage.
1. Disconnect the spark plug caps, and remove any dirt from around
2. Remove the spark plugs with a 13/16-inch spark plug wrench.
the spark plug area.
SPARK PLUG
3. Inspect the spark plugs. Replace
them if the electrodes are worn, or
if the insulator is cracked or
chipped. Clean the spark plugs with
a wire brush if you are going to
0.028-0.031in
reuse them.
(0.70-0.80 rnrn)
4. Measure the spark plug electrode
gap with
a suitable gauge. The gap
should be 0.028-0.031 in
(0.70-
0.80 mm). Correct the gap, if neces
sary, by carefully bending the side
electrode.
SPARK PLUG
WRENCH
A
5. Install the spark plug carefully, by
hand, to avoid cross-threading.
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Honda GX670 Specifications

General

Compression Ratio	8.3:1
PTO Shaft Rotation	Counterclockwise (from PTO shaft side)
Cooling System	Forced air
Ignition System	Digital CDI with variable timing
Lubrication System	Forced lubrication with trochoid pump
Engine Type	4-stroke, OHV
Displacement	670 cm³
Bore x Stroke	77 x 72 mm
Oil Capacity	1.9 L
Starting System	Electric starter
Net Power Output	22.1 HP at 3600 RPM