Generac Power Systems MDG25IF4, Owner'S Manual

Page: 31 / 60

Owner’s Manual for Mobile Generator 27
Operation
Low Idle Switch
Engine idle speed is 1,000 to 1,200 rpm. The engine will
start at idle speed and run at idle for 15 seconds no
matter what position the idle switch is in. After 15
seconds of running at idle, the unit will ramp up to 1,800
rpm if the idle switch is OFF. Otherwise the unit will
continue to idle if the idle switch is ON.
When the engine is at idle speed (1,000 rpm), the voltage
regulator will not function and the output voltage is
dropped out by the voltage regulator.
IMPORTANT NOTE: Do not apply load to the unit
when the engine is running at idle speed.
Cold Weather Operation
This unit may be equipped with cold-weather starting
aids such as coolant heater, oil pan heater, crankcase
ventilation heater, battery heater, and fuel heater.
See
Figure 3-2 . Starting aids are required below 32°F
(0°C). They will enhance starting performance below
these temperatures and may be needed to start
applications that have high parasitic loads during
cranking and start acceleration to idle. Other cold
weather starting aids are required at temperatures below
-13°F (-25°C) or at altitudes above 5,000 ft (1,500 m).
The use of correct grade oil is critical to achieving
adequate cold weather cranking speed. Synthetic oils
have improved flow at low temperatures.
NOTE: Contact a GMASD or refer to the applicable
engine service manual for more information.
The oil pan heater, crankcase ventilation (CCV) heater,
and fuel filter heater (if equipped); are activated with a
thermostat and will turn on and off as needed. The block
heater is powered by a shore power 120V electrical
connection that can be found in the convenience
receptacle. The CCV heater is powered by the generator
and will stay on when the engine is operating in cold
weather conditions. This heater is required for operation
below 32 °F (0 °C).
Figure 3-2. Cold Weather Starting Guidelines
Use cold weather starting aids as needed according to
Figure 3-2 . Follow supplier instructions for starting aids
provided on engine. A booster battery can be connected
if needed (see Using a Booster Battery or Charger (if
equipped) ).
NOTE: Turn key to ON but do not crank engine until
Engine Preheat Indicator goes off.
NOTE: Additional information on cold weather operation
is available from your local GMASD.
(000583)
DANGER
Explosion. Do not use ether when starting an
engine equipped with glow plugs or an air intake
heater. Doing so could cause an explosion, which
will result in death or serious injury.
A Fuel filter heaters
B Fuel filter heaters, CCV heater
C Fuel filter heaters, CCV heater, oil pan heater
D Fuel filter heaters, CCV heater, oil pan heater,
block heater
E Fuel filter heaters, CCV heater, oil pan heater,
block heater, 60/40 coolant
010913