Honda GX100 Assembly Instructions

GX100 Engine Assembly Information
OIL
RING
(COMBINATION
OIL RING
RINGS)
(COMBINATION RINGS)
20 mm (0.8 in)
"Z0D"
MARK
OIL
PISTON PIN
PISTON PIN CLIP (2)
Install so that the end gap
does not face the notch in
the piston.
END GAP
OIL
PISTON
NOTCH
CONNECTING ROD
LOCK PIN
GROOVE
VALVE SPRING (2)
VALVE STEM SEAL
(Intake valve only)
Do not reuse.
GOVERNOR
ARM SHAFT
CONNECTING ROD
LONG END
NOTICE:
Take care not to break
the piston ring when
installing the piston
assembly in the
cylinder.
VALVE GUIDE CLIP
(Exhust valve only)
GOVERNOR
ARM SHAFT
6 mm WASHER
6 mm THRUST
WASHER
GOVERNOR
SLIDER
GOVERNOR
HOLDER CLIP
GROOVE
GOVERNOR
HOLDER SHAFT
CRANKCASE COVER
OIL LEVEL SWITCH
GOVERNOR WEIGHT
(OPTIONAL)
HOLDER ASSEMBLY
CRANKCASE COVER/CRANKSHAFT/CYLINDER BARREL
12 mm FLANGE NUT
42 N·m (4.3 kgf·m,
31 lbf·ft)
Apply oil to the threads
and seat surface of the
nut, and tighten the nut.
VALVE SPRING RETAINER (2)
NOTICE: Do not remove the
valve spring retainer while the
piston is installed, or the valves
will drop into the cylinder.
SPARK PLUG
CR5HSB (NGK)
FLYWHEEL
Be sure that there is
no foreign material on
the magnetic part.
OIL
MARK
SECOND
RING
(BLACK
FACE)
PISTON
ASSEMBLY
6204 RADIAL
BALL BEARING
20 x 32 x 6 mm
OIL SEAL
INTAKE
VALVE
GUIDE
EXHAUST
VALVE GUIDE
CYLINDER BARREL
OIL
SECOND
RING
6 mm WASHER
REASSEMBLY:
Install inside
the cover.
8 mm LOCK PIN
"FW ▼" MARK
TOP RING
(CHROME FACE)
OIL
PISTON RINGS
MARK
OIL
TOP RING
VALVES/FLYWHEEL
CRANKCASE COVER/GOVERNOR
OIL
PISTON
EXHAUST VALVE
REASSEMBLY:
Before installation, remove carbon
deposits and inspect the valve.
12 mm WASHER
INTAKE VALVE
VALVE HEAD DIAMETER:
IN: 23 mm
EX: 21 mm
(0.9 in)
(0.8 in)
EXHAUST
INTAKE
SIDE:
SIDE:
6 x 25 (8)
WOODRUFF KEY
REASSEMBLY:
When installing the
flywheel, check to be
sure that the woodruff
key remains in its slot
on the crankshaft.
CONNECTING
GREASE
CRANKCASE COVER, CRANKSHAFT,
PISTON
(Apply grease
to
ROD CAP
CRANKCASE
COVER ASSEMBLY
TIMING BELT
Specified belt:
61 YU7 G-200
INSTALLATION:
Check that the belt is not
worn or cracked and do
not bend or twist the belt.
the oil seal lips.)
CAM PULLEY/ROCKER ARM/CYLINDER HEAD COVER
OIL
8 x 20 mm
DOWEL PIN (2)
CRANKSHAFT
INSTALLATION:
・Be careful not to damage
the oil seal.
・After installation, clean the
crankshaft tapered surface.
CONNECTING ROD CAP
CRANKSHAFT
OIL
CYLINDER
BARREL
OIL
MARKS
20 x 32 x 6 mm OIL SEAL
INSTALLATION: Be careful not to damage the
oil seal lips when installing the crankcase
cover with the oil seal.
GREASE
(Apply grease to the oil seal lips.)
TIMING
BELT
・Loosely tighten each 6 x 25 mm
flange bolts, then tighten in the
numbered sequence.
・Wait for approximately 20 minutes
after assembly before filling with
oil and starting the engine.
See the shop manual for additional information.
OIL
OIL
OIL
Do not
reuse.
"■" MARK
ALIGNMENT TIMING
MARKS
BELT
FLYWHEEL
FLANGE
INTAKE
ROCKER
ARM
CAM
PULLEY
6.8 x 1.9 mm
O-RING
CONNECTING ROD
BOLT (2)
5 N·m (0.5 kgf·m, 3.6 lbf·ft)
6204 RADIAL BALL BEARING
EXHAUST ROCKER ARM
OIL
PISTON
ASSEMBLY
CYLINDER
BARREL
LIQUID GASKET
APPLICATION AREA
(Hondabond HT, ThreeBond 1207 or
equivalent)
Assemble within 10 minutes after
applying the liquid gasket.
ROCKER
ARM
SHAFT (2)
VIEWED
FROM
PTO SIDE:
TIMING BELT
ALIGNMENT CAM
PULLEY
MARKS
OIL
ENGINE BED
"I" MARK
CYLINDER
BARREL
VALVE
ADJUSTING
LOCK NUT (2)
CUTOUT
OIL
CONNECTING
ROD BOLT (2)
FAN COVER TOP HOLE
OIL
ALIGNMENT
MARKS
HEAD COVER
OIL
VALVE
ADJUSTING
SCREW (2)
OIL
8 x 25 (4)
[Q and VEL types]
8 x 18 (4)
[S and W types]
TIMING BELT
CAM PULLEY SHAFT
・Apply a liquid gasket
HEAD COVER
(Hondabond HT,
VIEWED FROM
ThreeBond 1207 or
BACK SIDE:
equivalent) to the head
cover.
・Assemble within 10
minutes after applying the
liquid gasket.
・Wait for approximately 20
minutes after assembly
before filling with oil
LIQUID GASKET
APPLICATION AREA and starting the engine.
HEAD COVER
MATING SURFACE
・Install the cam pulley shaft in the
cylinder after setting the timing belt
on the cam pulley.
CAM PULLEY
ROCK ARM SHAFT
・Install the rocker arm shaft from the
opposite side of the cam pulley.
© Honda Motor Co., Ltd. 2009