APRILIA Pegaso 650, Service And Repair Manual

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8 - 19
REPAIRS
8.1.2 CARBURETTOR
8.1.3 RADIATOR
DEFECT SYMPTOM AND POSSIBLE CAUSE REMEDY
Difficult starting. 1) Starting jet clogged.
2) Starting duct clogged.
3) Air infiltration from gasket between cold start device body
and carburettor.
4) Cold start device choke not working correctly.
5) Battery partially exhausted.
Clean.
Clean
Check and tighten.
Repair.
Check and recharge.
Irregular operation at
idling or slow running. 1) Idling jet clogged or loose.
2) Air infiltration from carburettor or cold start device sleeve.
3) Cold start device choke not completely closed. Check and clean.
Check.
Check and clean.
Irregular operation at
medium or high speed. 1) Full-power jet clogged.
2) Taper needle encrusted and/or worn.
3) Throttle valve not working properly.
4) Filter clogged.
Check and clean.
Check and clean.
Check operation of throttle
valve.
Check and clean.
Overflow and fuel level
variations. 1) Needle valve worn or damaged.
2) Float not working properly.
3) Foreign matter sticking to needle valve.
4) Carburettor breather pipe clogged.
5) Needle valve spring broken of deformed.
6) Fuel level too high or too low. Change.
Check and adjust
Clean.
Clean.
Change.
Adjust fuel level.
DEFECT SYMPTOM AND POSSIBLE CAUSE REMEDY
Engine overheats. 1) Insufficient coolant.
2) Radiator blade unit clogged by dirt or foreign matter.
3) Thermostat valve defective, locked in closing position.
4) Coolant passages clogged.
5) Air in cooling circuit.
6) Coolant pump defective.
7) Use of unsuitable coolant.
8) Thermal switch defective.
9) Electrofan disconnected or faulty. Add coolant.
Clean.
Change.
Clean.
Bleed.
Change.
Change coolant.
Change.
Connect or change.
Engine does not reach
proper temperature. 1) Thermostat valve defective, locked in complete open posi-
tion.
2) Room temperature too cold.
3) Thermal switch defective.
4) Electrofan defective.
Change.
Put protective shield on
radiator.
Change.
Check or change.