Suzuki DF200 Service Manual page 125

3-64 ENGINE CONTROL SYSTEM
VACUUM PASSAGE INSPECTION
1. Disconnect vacuum hose 1 from vacuum switching valve
2.
2. Start engine and run it at idle speed.
Place a finger over vacuum hose end 1 and engine vacuum
is present.
3. If vacuum is not present, clean vacuum passage with com-
pressed air, start engine and check again for vacuum.
CHECK VALVE
Inspection
1. Remove check valve 1.
2. Blow air (moderate pressure) through hose fitting on black
side of check valve. Air should not pass through valve from
collector assembly (black side 3) to orange side 2.
3. Blow air (low pressure) through hose fitting on orange side of
check valve. Air should pass through to black side.
4. If air passes through valve in Step 2) or high pressure is
required to cause air to pass in Step 3), replace check valve.
#
DO NOT SUCK air through check valve.
Fuel vapor inside the valve is harmful.
5. Install check valve.
NOTE:
The check valve is directional. Refer to the figure for correct
installation.
4 To vacuum tank
5 From collector assembly
6 Vacuum tank