Service Data
3. Maintenance Data
escription
Cylinder Head
Cylinder
Piston
Piston Rings
Piston Pin
Crank Shaft
Connecting Rod
Reed Valve Stopper
Reed Valve
Engine Block
Carburetor
2-8
Item
uild up of carbon in combustion chamber
Distortion or damage on mating surface
Corrosion
Cooling water passage clogged
Mating surface scratches and wear
Diameter
Seizure, cylinder liner damage, or wear
Diameter
<Measure the external diameter at a point 11.5 mm
(0.45 in) above the lower edge of the piston skirt.>
Piston clearance
<The gap between cylinder and piston.>
Carbon build up on piston crown and in ring grooves
Scratch on the sliding surface
Measure clearance between piston ring and ring groove.
Measure piston pin hole diameter
Clearance between piston pin and pin hole
Ring end gap
Note : Measurement of ring end gap ; If ring gauge
is not available, use cylinder bore top or bottom
with small wear.
Outer diameter
Deflection <Measure with both ends supported.>
Gap between the connecting rod and
the crank web.
Lift height
Fails to close, is worn or damaged
Compression
Note : Remove all two spark plugs and measure
after warming with the throttle fully open.
Setting mark
Venturi bore
Main jet (MJ)
Main air jet (MAJ)
Main nozzle bore (MN)
Slow jet (SJ)
Slow air jet (SAJ)
Throttle opening (at WOT)
Pilot screw (PS)
Float height
Idling speed
Troling speed
Standard Values
0.03 mm/0.0012 in or less for scratches
0.03 mm/0.0012 in or less for distortion
0.03 mm (0.0012 in) or less for scratches
0.03 mm (0.0012 in) or less for distortion
¿60.00 mm/2.362 in
<0.5 oversize : 60.50mm (2.382in)>
¿59.95 Ð 59.97 mm/2.360 Ð 2.361 in
<0.5 oversize : 60.45 Ð 60.47 mm/2.380 Ð 2.381 in>
0.05 Ð 0.09 mm/0.00197 Ð 0.00354 in
Top:0.04 Ð 0.08 mm (0.0016 Ð 0.0032 in)
Second:0.02 Ð 0.06 mm (0.0009 Ð 0.0024 in)
¿14.00 mm/0.5512 in
-0.003 Ð +0.009mm/-0.00012 Ð +0.00035 in
Top /2nd: 0.20 Ð 0.40 mm/ 0.00787 Ð 0.01575 in
¿14.00 mm/0.5512 in
0.05 mm/0.0020 in or less
0.20 Ð 0.40 mm/0.00787 Ð 0.01575 in
6.0 Ð 6.2 mm/0.2352 Ð 0.2441 in
0.70 MPa/101.5 psi [7.1 kgf/cm
2
]
3LDO
22 mm/0.866 in
#122
#130
¿4/0.1575 in
#60
#125
72¡
1 + 1/2 ±1/4
14.5 ± 1 mm/0.571 ± 0.039 in
950~1000 rpm
850 rpm
2st X18E2 2012