Battery, Battery Box, and Leads

safety switch is mounted on the control panel and

the vicinity when servicing the battery.

connects in a line from the oil pressure gage. The

Batteries generate hydrogen gas, which

is highly explosive.

operating oil pressure is 4 to 5 psi. When the oil

pressure drops to 1 psi, the oil pressure safety

(2) Start engine and allow it to run for 10 to

switch is tripped and closes the ground circuit to the

15 minutes. Stop the engine and check the battery

magneto to stop the engine. This protects the

with a hydrometer. A fully charged battery shall

engine from wear due to lack of oil. You must reset

have a minimum specific gravity of 1.275 at 75 F.

the switch plunger after each engine shutdown

(3) If the specific gravity of the electrolyte is

before you can restart the engine. The spring reset

less than 1.250, the battery must be charged before

clip will kick out after the engine starts and suf-

use. When you charge the battery, use a constant

ficient oil pressure builds up. After that the switch

current charger. Check the specific gravity of the

will be operative.

electrolyte every 30 minutes. The battery is fully

g. Control Panel. The engine controls and in-

charged when you get a constant specific gravity

struments are mounted on the control panel which

reading for three 30-minute intervals.

is located on the pump piping assemblies. Refer to

CAUTION

figure 1-3 for the wiring diagram showing the

Constant-current battery charging is

electrical connections between the engine and

always preferred. If you must use a

controls. The function of the controls and in-

constant-potential charger, battery

struments is described in table 2-1.

temperatures must be maintained at less

h. Starter Switch. The starter switch, mounted

than 130F by interrupting the

on the control panel, closes the circuit to energize

charging procedure as this temperature

the starting motor. W h e n the pushbutton is

is approached.

released, the starting motor deenergizes. Care

(4) During charging, check the electrolyte

should be taken that you do not energize the

level frequently. A d d d i s t i l l e d w a t e r w h e n

starting motor while the engine is running.

necessary to maintain the battery electrolyte level.

i. Magneto Switch. When you depress the

Continue charging after adding water to assure

magneto switch on the control panel, it will ground

proper mixing of the solution.

the magneto and stop the engine. This switch is in

(5) Charge the battery a minimum of once

the same circuit as the oil presssure safety switch.

each month when the battery is not in service. If the

battery fails to take or maintain a charge, replace it.

4-23. Battery, Battery Box, and Leads

b. Removal and Disassembly.

a. Service. To charge b a t t e r y , proceed as

(1) Remove two wing nuts (1, fig. 4-8) that

follows:

secure cover (2) to the battery box (10); remove

(1) Remove caps and check the electrolyte

cover.

level in each cell. If any are low, fill to proper level

with distilled water.

WARNING

Do not smoke or use an open flame in

4-16