Figure 5-8. Voltage Regulator Test Setup

(2) Turn on all accessory load (lights) and connect

an additional load across the battery (such as a carbon

pile or bank of lights) so as to drop the system voltage

approximately one volt below the voltage regulator

setting.

(3) Operate generator at specified speed for 15

minutes with cover in place. (This stabilizes operating

temperature.)

(4) Cycle generator with variable resistor and note

current setting.

5-68. GENERATOR REGULATOR REPLACEMENT.

a. Removal.

(1) Disconnect and tag leads at BAT, GEN

and F terminals of regulator (fig. 5-10).

Figure 5-8. Voltage Regulator Test Setup

CAUTION

(2) Move voltmeter lead from GEN to BAT terminal.

Lead at BAT terminal is a hot lead.

Operate generator at charging speed for 15 minutes.

Do not let it contact the vehicle

frame.

NOTE

Disregard amount of current flowing

during this test: however, it is

important that the ignition be the only

electrical load on the system at this

time.

(3) Cycle the generator with the variable resistor, to

a 4 volt reading at the GEN terminal, then cut out the

resistor and note voltage reading at the BAT terminal.

Compare with values in Table 2-1.

c. Current Regulator Test.

(1) Connect ammeter into charging circuit, as in

Figure 5-10. Regulator, Installed

(2) Remove three holddown screws, nuts and

washers, and remove regulator and radio suppression

capacitor.

b. Installation. Reverse procedure in a. above,

connecting capacitor lead to the regulator BAT terminal.

5-69. BATTERY SERVICING.

5-70. SPECIFIC GRAVITY TEST. Specific gravity

testing of the battery electrolyte determines the state of

charge in each battery cell. Use a hydrometer and

Figure 5-9. Current Regulator Test Setup

thermometer, correcting the hydrometer reading for

temperature. A corrected specific gravity reading of

1.275 in each cell