90. DESCRIPTION (fig. 55).

a. The generator is shunt connected. The two field coils, regulating coil, and shunt coil are not connected in series in the conventional manner. The regulating field coil provides adequate current output (approx. 4 amperes) for daytime operation. The shunt field coil is controlled through the ignition and light switch to increase current output (approx. 8 amperes) when vehicle lights are in use. Generator uses the third (regulating) brush system of current regulation. A cut‐out relay serves as a magnetic switch in the generator‐battery circuit, also operating the instrument panel green signal light to indicate generator charge.

91. CLEAN COMMUTATOR (fig. 56).

a. If battery is in good condition, cut‐out relay is functioning, and wiring connections are made according to diagram (fig. 55), yet generator does not charge or charge rate is low, proceed to clean the commutator.

(1) Remove left footboard, sidebar, and clutch foot pedal assembly, following procedure outlined under paragraph 102 a (1) to (6), to permit generator cover removal.

(2) Remove the two end cover screws and pull end cover off generator.

(3) Clean armature commutator with No. 00 sandpaper until bright and clean. Blow out with air. CAUTION: Do not remove or disturb brushes in their holders. Never use emery cloth to clean the commutator.

(4) Temporarily install footboard assembly and operate engine, to observe whether or not generator is charging (green signal light goes off at above 20 mph). If cleaning commutator does not remedy generator charge, and/or commutator is badly worn, then generator must be replaced (par. 93). If cleaning of commutator remedied generator charge, reinstall generator end cover, and the footboard and clutch pedal assembly (par. 102 b).

92. ARMATURE BEARING SPECIAL LUBRICATION (fig. 57).

a. At the 6,000–mile second echelon preventive maintenance service period, the commutator end bearing must be hand‐packed. In performing this operation, care must be taken not to shift or move the generator third (regulating) brush, thus disturbing generator current regulation. Generator drive end bearing is adequately lubricated by oil circulating through engine.

b. To Lubricate Commutator End Bearing.

(1) Remove left footboard, sidebar, and clutch pedal assembly, following procedure outlined in paragraph 102 a (1) to (6).

(2) Remove the two end cover screws and pull end cover off generator.

(3) Remove two of the three screws which secure the outer grease retainer plate to end of generator (fig. 57).

(4) Loosen the other grease retainer plate screw slightly to permit shifting plate to one side.

(5) Pack ball bearing with general purpose grease No. 2, pressing lubricant into bearing with finger.

(6) Shift the outer grease retainer plate back into position. Install the two screws removed, and securely tighten all three screws.

(7) Install generator end cover and the two retaining screws.

(8) Install left footboard, sidebar, and clutch foot pedal assembly, following procedure outlined in paragraph b.

93. REMOVE GENERATOR (figs. 58 and 59).

a. Generator is gear driven through engine timing gear train. Generator can be removed and installed without removing timing gear case cover, or affecting alinement of timing gears.

b. Before replacing generator because of failure of instrument panel green signal light to indicate charge, check panel light wiring and bulb for good condition (par. 120).

c. When it has been determined that generator must be removed for replacement, proceed as follows:

(1) Disconnect wires from the two generator terminals marked SWITCH and RELAY.

(2) Remove the two long screws, through timing gear case cover, that secure end of generator against gear case (fig. 58).

(3) Remove strap nut, lock washer, and curved washer from end of strap that clamps generator in its cradle on engine crankcase (fig. 59).

(4) Lift strap high enough to permit raising generator so that oil slinger (on end of generator gear) will clear adjacent gear, and allow generator to be removed from engine. Be sure to observe and count number of paper shims between generator and cradle. Lay these shims aside to be used again when generator is reinstalled. Also, note location of hole in shims for oil drain. These shims were required in original assembly to adjust driving gears for proper mesh and, if left out, gears may mesh too deeply and “howl,” even though considerably worn. Unless a new generator gasket is available, to be used when generator is reinstalled, be careful not to damage the old one.

94. INSTALL GENERATOR.

a. When installing generator, the important point to consider is correct shimming of generator in its cradle to provide correct mesh of driving gear with intermediate timing gear. Make sure same number of paper shims are used in reassembling as were found underneath generator when it was removed. After an engine has been run a considerable length of time and gears have worn to some extent, they have possibly developed sufficient lash or play to safely remove one or more of the original shims, and thus affect closer meshing and quieter operation. However, this should not be done unless timing gear case cover is removed so that gear mesh and lash can be carefully checked.

(1) Pass generator drive gear end through gear case hole, lifting generator so that oil slinger clears intermediate timing gear. Turn generator in its cradle so that end holes line up with long mounting screws which pass through gear case cover. Tighten mounting screws securely.

(2) Install curved washer, lock washer, and nut on end of clamp strap; tighten nut securely.

(3) Connect red‐black wire to generator terminal marked RELAY, and green wire to generator terminal marked SWITCH. Refer to wiring diagram (fig. 55).

(4) Operate engine and check generator for current output, as well as check for gear noise. If shimming under generator is proper, generator and timing gears will run quietly. If necessary, readjust shimming until gears operate quietly.

95. CUT‐OUT RELAY.

a. Operation of the instrument panel green signal light, indicating generator charge, is controlled by the cut‐out relay. Therefore, if relay is faulty the signal light will not operate properly, falsely indicating generator trouble. Rust around the contact points, burned points, and loss of armature spring tension are sources of most relay trouble. NOTE: Before condemning a relay because of failure of green signal light, make light test (par. 120).

b. Correct adjustment of relay point gaps and tensioning of armature springs require use of precision electric meters and expert knowledge on the subject. A faulty relay, other than removing cover and cleaning with air, should be replaced. No adjustment of points should be attempted.

c. Remove.

(1) Disconnect the three wires from relay terminal screws.

(2) Remove the two mounting screws and lock washers. Remove relay from engine base.

d. Install.

(1) Mount relay on engine base with two screws and lock washers. Make sure that mounting is clean to make good electrical ground contact between relay and engine.

(2) Reconnect the three wire terminals to relay terminal screws. Follow wiring diagram, figure 55.

(3) Operate engine and observe action of relay, also action of instrument panel green signal light to indicate generator charge.