Alternator - TM-10-3930-630-120072

TM 10-3930-630-12

CAUTION

(b) Inspect

sending

units

for

evidence of oil leakage where unit and fittings thread

Apply pressure with pry bar against stator

into crank-case.

laminations, not against end frames.

(2) Removal

(5) Place pry bar as shown on figure 4-34

(a) Remove nuts and lockwashers

and pry alternator away from engine until correct

deflection

and disconnect wires from sending units (fig. 4-33).

(b) Use a wrench on the hex and

remove oil pressure sending unit from crankcase.

Remove hourmeter actuator sending unit.

(c) Remove elbow and tee from

crankcase.

(3) Installation.

(a) Install tee and elbow in

crankcase.

(b) Install sending units (fig. 4-33) in

tee.

(c) Install wires on sending units and

secure with nuts and lockwashers.

c. Coolant Temperature Gage Sending Unit.

The coolant temperature sending unit (fig. 4-28) is

mounted on the top rear end of the cylinder head.

(1) Inspection. Lift seat and prop in open

position to gain access to coolant temperature sending

unit.

(a) Check wire connection at coolant

Figure 4-34. Fan belt adjustment.

temperature sending unit (fig. 4-28).

is obtained.

(b) Check sending unit installation in

(6) Tighten adjusting brace screw to hold

head for evidence of leakage.

alternator in position. Remove pry bar.

(2) Removal

c. Voltage Test. Turn ignition switch on.

(a) Drain radiator (para 4-68).

(1) Connect a voltmeter between "BAT"

(b) Remove nut and lockwasher and

terminal (fig. 4-36) and ground. Voltmeter should read

disconnect wire from coolant temperature sending unit

10.7 to 12 volts.

(fig. 4-28).

(2) Connect a voltmeter between No. 1

(c) Remove temperature sending

terminal (fig. 4-36) and ground. Voltmeter should read

unit from cylinder head.

10.7 to 12 volts.

(3) Installation.

(3) Connect a voltmeter between No. 2

(a) Install

coolant

temperature

terminal (fig. 436) and ground. Voltmeter should read

sending unit (fig. 4-28) in threaded opening in cylinder

10.7 to 12 volts.

head.

(4) A zero reading on the voltmeter

(b) Connect wire to sending unit and

indicates an open circuit. Check wiring harness and

secure with nut and lockwasher.

wiring and correct.

(c) Fill cooling system (para 4-68).

(5) If there is an open circuit from No. 2

terminal the alternator internal circuits will prevent

4-51.

Alternator

current output.

a. General. The alternator is mounted on the

d. Amperage Test.

right side of the engine. A belt drives the alternator and

(1) Disconnect battery ground cable.

fan. Incorporated into the alternator is a voltage

(2) Connect a carbon pile or load rheostat

regulator which prevents over-charging the battery.

in series with the "BAT" terminal (fig. 4-36) as shown on

b. Belt Adjustment.

figure 4-37.

(1) Open right side panel.

(3) Connect battery ground cable.

(2) Check

belt

deflection

between

(4) Operate engine at moderate speed

alternator pulley and fan pulley (fig. 4-34).

and adjust load rheostat to obtain maximum alternator

(3) Deflection should be %-inch midway

output.

between pulleys.

(5) If ammeter reads 27 to 37 amps,

(4) If adjustment is necessary, loosen

alternator is not defective.

screw attaching alternator to adjusting brace (fig. 435).

4-44