Generac Power Systems GTH760, Service Manual

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6-4
2. Place battery in holder with flat base. Tighten hold down
evenly until snug. do NoT overtighten.
3. Connect positive terminal to positive post
FIrST
to
prevent sparks caused by accidental grounding. Tighten
connectors securely.
4. Connect negative terminal to negative battery terminal.
Tighten connectors securely.
CHECKING BATTERY:
1. Physical check – clean if necessary.
a. Corrosion
b. Dirt
c. Terminal and clamps (secure – good condition)
2. Bring battery to full charge.
*
wArNING: do NoT exceed charge rate of 1/10
ampere for every ampere of battery rating. Consult
battery manufacturer for maximum charge recom-
mendations.
a. use a "Trickle" charge (automatically reduces
charge rate).
b. Fill non-sealed battery cells with distilled water after
charging (for batteries that have been in service).
Note: If battery gets “Hot” to the touch or is spitting acid
(gassing) excessively, unplug charger periodically.
3. With battery fully charged, check specific gravity readings
of each cell with a Battery Hydrometer and record readings
(Figure 6-5). All readings should be above 1.250 (compen-
sating for temperature). If specific gravity readings varied
0.50 or if all cells read less than 1.225, replace battery.
CHECK EACH CELL
AFTER CHARGING
USE A TEMPERATURE
COMPENSATE
D
HYDROMETER
Figure 6-7. Checking 12 Volt Battery Cells
TESTING BATTERY:
Set a digital multimeter to read DC Volts.
Attach RED meter test lead to po) battery terminal.
Attach BLACK meter test lead to negative (-) battery terminal.
With ignition switch “OFF,” press starter button. If ignition
switch and starter switch are the same switch, disconnect
wires from spark plugs and ground ignition using two Ignition
Testers. Turn switch to “START.” Meter should display 9 volts
or more while cranking engine. If less than 9 volts is measured,
replace battery.
*
CAuTIoN: do not crank starter motor for more than
15 seconds without allowing starter motor to cool
at least 2 minutes.
BATTERY RECOMMENDATIONS:
The minimum battery size recommended is 450 CCA@0°F.
BATTERY CABLE RECOMMENDATIONS:
These cable sizes are based on total length of cable from
battery positive post to starter, plus ground return to battery
negative post.
#4 AWG — 1.8 meters (6 ft.) or less
#2 AWG — 3.7 meters (12 ft.) or less
oPTIoNAl wIre HArNeSS
Engines supplied with a wire harness have a Packard four or
five terminal female plug on the harness (see Figure 6-12). The
wire harness consists of four colored wires as follows:
• A brown wire is used to signal low oil pressure. When low oil
pressure is detected, this wire becomes a ground. Otherwise
it is open.
• A yellow wire is used to ground the ignition. Connect this
wire to ground and the ignition will be shut off.
• A white wire is connected to +12 Volts DC and the carbure-
tor, which allows fuel to flow. Turn off the +12 Volt supply,
and the fuel solenoid will close, stopping the flow of fuel.
• An orange wire (red on some models) is used to start the
engine. 12 Volts DC to this wire and the starter
solenoid will engage. Turn off the +12 volt supply, and the
starter will disengage.
Figures 6-8 through 6-10 show the proper connections for
the wiring harness and how it is routed.
SeCTIoN 6: eleCTrIC STArTer