GENERAL
The Model 165 has a six-volt generator-battery electrical system with
negative ground return.
Power is produced by a 6 pole, 4 brush, shunt generator. The armature
assembly is driven by the flywheel generator shaft, rotating in a
magnetic field produced by the field coils and pole shoes in the
generator frame. Resulting current induced in the armature windings is
picked up from the commutator segments by 4 brushes.
The generator output is controlled by a voltage regulator, which
regulates the generator field strength. The generator itself has no
adjustment for control of output. The voltage regulator functions to
increase battery charging rate when battery is low or when lamps are
lighted, and to decrease charging rate when battery is near fully
charged. The voltage regulator requires no regular interval attention. A
cutout relay is combined with the voltage regulator as a single unit.
CHECKING GENERATOR
If the generator or voltage regulator is suspected of being faulty as
indicated by the battery becoming discharged, check the electrical
system in the following sequence to determine which part is not
functioning properly.
1. Remove red wire at voltage regulator ,,GEN,, terminal. Using a 0-15,
D.C. ammeter, connect one lead to the terminal, the other to the red
wire. Turn on head lamp and start engine. Open throttle to an engine
speed equivalent to 20 - 25 MPH. road speed. The ammeter should show a
charge when generator is warmed to operating temperature.
2. If generator does not show a charge on ammeter, after above test,
remove green wire from "F” terminal on regulator and touch it to engine
base. If ammeter shows a charge of five amperes or more, the defect is
in the voltage unit of voltage regulator or the regulator is not
grounded. Carefully check the regulator and battery holder to be
absolutely sure of a good ground.
3. Check regulator against wiring diagram to see that it is wired
properly. Momentarily short the voltage regulator "GEN" and "BAT"
terminals by touching a piece of wire or screwdriver shank across them.
This will polarize the generator and energize the pole shoes with
residual magnetism. When the generator is not polarized with the
battery, the generator will not charge and the relay contact points will
arc. If operated in this condition the regulator points will burn.
Operate engine (after polarizing generator) as described in step one. If
generator does not charge, proceed to step four.
4. Remove ammeter lead from regulator "GEN" terminal and attach it to
battery positive terminal. Touch "F" terminal green wire to engine base.
With regulator out of generator circuit and ammeter still showing no
charge with engine operating as previously, trouble is in the generator.
5. Before removing and completely disassembling generator, check the
brushes and brush springs and polish the commutator with No. 00
sandpaper. Make sure brushes are not worn to the point where the brush
wire limits contact with the commutator.
If upon further checking generator is still not functioning properly,
disassemble the generator as necessary, following sequence described in
"Disassem-bling Generator," and follow subsequent checking and repairing
procedures.
TESTING FIELD COILS
Initial testing of generator field coil circuit can be made with
generator frame in place. Disconnect red and green wires from regulator
terminals and remove the positive brushes from frame (the brushes
connected to same terminal as red wire).
1. Connect a fully charged six-volt battery with ammeter in series to
the red and green wires removed from regulator. The complete field
circuit should draw two amperes.
[caution]
Overloading ammeter by showing a short circuit will damage it. An
overload is indicated by needle going beyond range of scale. Contact
must be broken immediately to avoid damage to meter. In making all
tests, make only a momentary contact to determine if a short exists. If
needle doesn't go beyond calibrated scale, it is safe to make sustained
contact.
2. When a short is indicated in above test or if reading is higher or
lower than specified amounts, remove red and green wires and field coil
leads from terminals and take reading directly from field coil leads.
3. Carefully check red and green wires if reading is correct as taken in
step two. If wires are found to be serviceable and a short did exist in
step one, check the frame terminals. They should be insulated from each
other and from the generator frame. Check positive brush holders. They
must be insulated from generator frame.