ENGINE
3-9
7. Install:
●
Spark plug
NOTE:
Before installing the spark plug, clean the spark
plug and gasket surface.
8. Connect:
●
Spark plug cap
EAS20710
MEASURING THE COMPRESSION
PRESSURE
The following procedure applies to the cylinder.
NOTE:
Insufficient compression pressure will result in a
loss of performance.
1. Measure:
●
Valve clearance
Out of specification
→
Adjust.
Refer to “ADJUSTING THE VALVE CLEAR-
ANCE” on page 3-3.
2. Start the engine, warm it up for several min-
utes, and then turn it off.
3. Disconnect:
●
Spark plug cap
4. Remove:
●
Spark plug
CAUTION:
ECA13340
Before removing the spark plugs, use com-
pressed air to blow away any dirt accumulat-
ed in the spark plug wells to prevent it from
falling into the cylinders.
5. Install:
●
Compression gauge “1”
●
Extension “2”
6. Measure:
●
Compression pressure
Out of specification
→
Refer to steps (c) and
(d).
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Set the main switch to “ON”.
b. With the throttle wide open, crank the engine
until the reading on the compression gauge
stabilizes.
WARNING
EWA12960
To prevent sparking, ground the spark plug
lead before cranking the engine.
c. If the compression pressure is above the
maximum specification, check the cylinder
head, valve surfaces and piston crown for
carbon deposits.
Carbon deposits
→
Eliminate.
d. If the compression pressure is below the
minimum specification, pour a teaspoonful of
engine oil into the spark plug bore and mea-
sure again.
Refer to the following table.
Spark plug
18 Nm (1.8 m•kg, 13 ft•lb)
Compression gauge
90890-03081
Engine compression tester
YU-33223
Extension
90890-04082
T
R
.
.
Compression pressure (standard)
1200 kPa/300 r/min (12 kgf/cm
2
/
300 r/min)
Compression pressure (maxi-
mum)
1300 kPa/300 r/min (13 kgf/cm
2
/
300 r/min)
Compression pressure (minimum)
1050 kPa/300 r/min (10.5 kgf/cm
2
/
300 r/min)
1
2
Summary of Contents for XG250
Page 1: ...SERVICE MANUAL XG250 4D6 28197 E0 ...
Page 39: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 2 23 LUBRICATION DIAGRAMS ...
Page 41: ...CABLE ROUTING 2 25 CABLE ROUTING ...
Page 43: ...CABLE ROUTING 2 27 ...
Page 45: ...CABLE ROUTING 2 29 ...
Page 47: ...CABLE ROUTING 2 31 ...
Page 49: ...CABLE ROUTING 2 33 ...
Page 217: ...CARBURETOR 6 8 ...
Page 218: ...AIR INDUCTION SYSTEM 6 9 EAS27040 AIR INDUCTION SYSTEM ...
Page 222: ...AIR INDUCTION SYSTEM 6 13 ...
Page 237: ...CHARGING SYSTEM 7 14 ...
Page 241: ...LIGHTING SYSTEM 7 18 ...
Page 247: ...SIGNALING SYSTEM 7 24 ...
Page 251: ...CARBURETOR HEATING SYSTEM 7 28 ...
Page 252: ...ELECTRICAL COMPONENTS 7 29 EAS27970 ELECTRICAL COMPONENTS 1 2 3 4 5 6 8 7 9 ...