Vento zipr3i, Service Manual

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Rev 01/ page121 of 143
Spark plug
electrodes
overheat or
burn. 1. Spark plug too hot.
2. The engine overheats.
3. Spark plug loose.
4. Mixture too lean.
5. Not enough engine oil. Replace by cold type plug,
Tune up.
Retighten.
Adjust carburetor.
Check oil pump.
Magneto does
not charge. 1. Open or short in lead wires, or loose lead
connections.
2. Shorted, grounded or open magneto coil.
3. Shorted or open regulator/rectifier.
Repair or retighten.
Replace.
Replace.
Magneto
charge, but
charging rate is
below the
specifications. 1. Lead wires tend to get shorted or open-circuited
or loosely connected at terminal.
2. Grounded or open-circuited stator coils of
magneto.
3. Defective regulator/rectifier.
4. Defective cell plates in the battery,
Repair or retighten.
Replace.
Replace.
Replace the battery.
Magneto
overcharges. 1. Internal short-circuit in the battery.
2. Resistor element in the regulator/rectifier
damaged or defective.
3. Regulator/rectifier unit poorly grounded.
Replace the battery.
Replace.
Clean and tighten ground
connection.
Complaint
7) Symptom and possible causes
(ii) Remedy
Unstable
charging. 1. Defective regulator/rectifier.
2. Lead wire insulation frayed due to
vibration, resulting in intermittent
shorting.
3. Magneto coil internally shorted.
(b)
Repair or replace.
Replace.
(i) Replace.
Starter button
is not effective.
1. Battery runs down.
2. Defective switch contacts.
3. Brushes not seating properly on
commutator in starter motor.
4. Defective starter relay.
5. Defective starter pinion gears
6. Defective front or rear brake light
switches circuit.
Recharge and replace.
Replace.
Repair or replace.
Replace.
Replace.
Repair or replace.