Generac Power Systems G1000M User manual

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Questions?
Before taking your unit
back to the store,
call the generator
helpline at
1-800-270-1408
M-F 8-5 CT
Portable Generator Owner’s Manual
This is the safety alert symbol. It is used to alert you to potential personal injury hazards.
Obey all safety messages that follow this symbol to avoid possible injury or death.
Model No. 1532-1 (1000 Watt AC Generator) Manual No. 187970 Revision 0 (4/12/2001)
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G1000M

Generac Portable Products G1000M Generator
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EQUIPMENT
DESCRIPTION
This generator is an engine-driven, revolving field,
alternating current (AC) generator. It was designed to
supply electrical power for operating compatible light duty
electrical lighting, tool, and motor loads. This manual
contains information for a generator that operates 120 Volt
AC, single phase, 60 Hz devices that require up to
1,000 watts (1.0 kW) peak power that pull up to 7.5 Amps
at 120 Volts AC or 8.3 Amps at 12 Volts DC.
CAUTION! Do Not exceed the generator’s
wattage/amperage capacity. Add up the rated watts
of all devices you are connecting to generator
receptacles at one time. This total should not be
greater than 1,000 watts. In most cases rated watts
of the electrical device can be found on the device
nameplate. If the device nameplate gives only volts
and amps, multiply volts times amps to obtain watts
(volts X amps = watts).
The G1000M generator has the following features:
• 120 Volt AC, 7.5 Amp receptacle with circuit breaker.
• 12 Volt DC, 8.3 Amp accessory receptacle with circuit
breaker.
• Low Oil Shutdown: Automatically shuts down the engine
if oil drops below safe operation level.
• 1.2 gallon (4.5L) overhead fuel tank.
• The generator’s revolving field is driven at about
3,600 rpm by a Mitsubishi 2.4 h.p. engine.
WARNING! Do Not tamper with engine
governed speed. High operating speeds are
dangerous and increase risk of personal injury or
damage to equipment. The generator supplies
correct rated frequency and voltage only when
running at proper governed speed. Incorrect
frequency and/or voltage can damage some
connected electrical loads. Operating at excessively
low speeds imposes a heavy load. When adequate
engine power is not available engine life may be
shortened.
SAFETY RULES
This generator set was designed and manufactured for
specific applications. Do Not attempt to modify the unit
or use it for any application it was not designed for. If you
have any questions about your generator’s application, ask
your dealer/distributor or consult the factory.
The manufacturer could not possibly anticipate every
circumstance that might involve a hazard. For that reason
warnings in the manual and warnings on tags or decals
affixed to the unit are not all–inclusive. If you intend to
handle, operate or service the unit by a procedure or
method not specifically recommended by the manufacturer,
first make sure that such a procedure or method will not
render this equipment unsafe or pose a threat to you and
others.
Read this manual carefully and become familiar
with your generator set. Know its applications, its
limitations and any hazards involved.
DANGER! You must isolate the generator from
the electric utility by opening the electrical system’s
main circuit breaker or main switch if this unit is
used for backup power. Failure to isolate the
generator from the power utility may result
in injury or death to electric utility workers
and damage to the generator due to a backfeed
of electrical energy. Whenever unit is providing
backup power, the electric utility must be notified.
DANGER! Generator exhaust gases contain
DEADLY carbon monoxide gas. Carbon
monoxide, if breathed in sufficient
concentrations, can cause unconsciousness or
death. Operate this equipment outdoors where
adequate ventilation is available.
The Emission Control System for this generator is
warranted for standards set by the Environmental
Protection Agency. For warranty information refer to the
engine owner’s manual.
The engine exhaust from this product
contains chemicals known to the State
of California to cause cancer, birth
defects, or other reproductive harm.
WARNING:

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• The generator produces a very powerful voltage that can
cause serious injury or death by electrocution. Never
touch bare wires or receptacles. Never permit a child
or any unqualified person to operate the generator.
•Never handle any kind of electrical cord or device while
standing in water, while barefoot or while hands or feet
are wet. Death or serious injury from electrocution may
result.
• Use a ground fault circuit interrupter (GFCI) in any damp
or highly conductive area (such as metal decking or steel
work).
•Never use worn, bare, frayed or otherwise damaged
electrical cords with the generator. Death, serious injury
and property damage from electrical shock may result.
•Gasoline is highly FLAMMABLE and its vapors
are EXPLOSIVE. Never allow smoking, open
flames, sparks or heat in the vicinity while
handling gasoline. Avoid spilling gasoline on a hot
engine. Comply with all laws regulating storage and
handling of gasoline.
•Do Not overfill the fuel tank. Always allow room for
fuel expansion. If tank is overfilled, fuel can overflow
onto a hot engine and cause a FIRE or an
EXPLOSION.
•Never store a generator with fuel in the tank where
gasoline vapors might reach an open flame, spark or pilot
light (as on a furnace, water heater, clothes dryer). FIRE
or an EXPLOSION may result.
• The unit requires an adequate flow of cooling air for its
continued proper operation. Never operate the unit
inside any room or enclosure where the free flow of
cooling air into and out of the unit might be obstructed.
Allow at least 2 feet of clearance on all sides of generator,
even while operating unit outdoors, or you could damage
the unit.
•Never start or stop the unit with electrical loads
connected to receptacles with the connected devices
turned ON. Start the engine and let it stabilize before
connecting any electrical loads. Disconnect all electrical
loads before shutting down the generator.
•Do Not insert any object through cooling slots of the
engine. You could damage the unit or injure yourself.
•Never operate the generator:
in rain; in any enclosed compartment; when connected
electrical devices overheat; if electrical output is lost; if
engine or generator sparks; if flame or smoke is
observed while unit is running; if unit vibrates
excessively.
GROUNDING THE
GENERATOR
The National Electrical Code requires that the frame and
external electrically conductive parts of this generator be
properly connected to an approved earth ground. Local
electrical codes may also require proper grounding of the
unit. For that purpose, a GROUNDING WING NUT is
provided on the generator housing (Figure 1).
Generally, connecting a No. 12 AWG (American Wire
Gauge) stranded copper wire to the grounding wing nut
and to an earth-driven copper or brass grounding rod
(electrode) provides adequate protection against electrical
shock. Be careful to keep the grounding wire attached after
connecting the stranded copper wire. However, local codes
may vary widely. Consult with a local electrician for
grounding requirements in your area.
Properly grounding the generator helps prevent electrical
shock if a ground fault condition exists in the generator or
in connected electrical devices. Proper grounding also helps
dissipate static electricity, which often builds up in
ungrounded devices.
Figure 1 — Grounding Wing Nut
Grounding Wing Nut

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12 Volt DC, 8.3 Amp Accessory Jack — May be used
to power 12 Volt DC electrical devices or recharge 12 Volt
DC batteries.
120 Volt AC, 7.5 Amp Receptacles — May be used to
supply electrical power for the operation of 120 Volt AC,
single phase, 60 Hz electrical lighting, appliance, tool and
motor loads.
Air Cleaner — Uses a foam element to limit the amount
of dirt and dust that enters the engine.
Choke Lever — Used to manually provide proper starting
mixture when engine is cold.
Circuit Breaker (AC) — Receptacles are provided with a
push-to-reset circuit breaker to protect the generator
against electrical overload.
Engine ON/OFF Switch — Used to stop a running
engine.
Fuel Shut-Off Valve — Use this valve to turn the fuel
supply on and off.
Fuel Tank — Capacity of 1.2 U.S. gallons (4.5 liters) of
fuel.
Grounding Lug — Use this connection to properly
ground the generator. See ”Grounding the Generator” on
page 6.
Oil Fill/Drain — Access to oil fill dipstick and engine oil
drain plug.
Recoil Starter — Used for starting the engine.
Spark Plug — Access to engine spark plug.
KNOW YOUR GENERATOR
Read this owner’s manual and safety rules before operating your generator.
Compare the illustrations with your generator to familiarize yourself with the locations of various controls and
adjustments. Save this manual for future reference.
120 Volt AC, 7.5 Amp
Receptacle
Recoil Starter
Circuit Breaker (AC)
Oil Fill/Drain
(inside cover)
Choke Lever
Spark Plug (inside
cover) Fuel Tank
Air Cleaner
Grounding Lug
12 Volt DC, 8.3 Amp
Accessory Jack
Engine ON/OFF Switch
Fuel Shut-Off Valve

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CONTENTS
Check all contents. If any parts are missing or damaged, call
the generator helpline at 1-800-270-1408. Shipped with
your generator is:
• Main unit
• Oil bottle
• Owner’s manual
• Battery charge cables
BEFORE STARTING ENGINE
Add Oil
NOTE: When adding oil to the engine crankcase in the
future, use only high quality detergent oil rated with API
service classification SG, SF/CC, CD. Select the oil’s
viscosity grade according to your expected operating
temperature:
SAE 10W-30 is recommended for general all temperature
use. Multi-viscosity oils (10W30, etc.) improve starting in
cold weather, but these oils will result in increased oil
consumption. Check your engine oil level more frequently
to avoid possible damage from running low on oil.
To Add Engine Oil:
• Place the generator on a level surface.
• Remove the oil fill cover.
• Remove oil filler cap and wipe dipstick clean (Figure 2).
• If the oil level is not at the point of overflowing from the
oil filler neck, slowly fill engine with recommended oil.
• Reinstall oil filler cap and tighten securely.
• Replace the oil fill cover.
• Check the engine oil level before starting each time
thereafter.
Add Gasoline
WARNING! Never fill fuel tank indoors. Never
fill fuel tank when engine is running or hot. Do Not
light a cigarette or smoke when filling the fuel tank.
CAUTION! Do Not overfill the fuel tank.
Always leave room for expansion.
• Use clean fresh UNLEADED gasoline with a pump rating
of 86 or higher. Do Not use premium or leaded
gasoline. Do Not mix oil with gasoline.
• Clean area around fuel fill cap, remove cap.
• Check the fuel level.
• If fuel level is low, slowly add recommended gasoline to
fuel tank, up to the shoulder of the fuel strainer
(Figure 3). Be careful not to overfill (there should be no
fuel in the filler neck).
NOTE: Occasionally clear the fuel strainer of any dirt,
rust, or other particulate matter.
• Install fuel cap and wipe up any spilled gasoline.
Occasionally you may hear a light “spark knock” or
“pinging” (metallic rapping noise) while operating under
heavy loads. This is no cause for concern. If spark knock or
pinging occurs at a steady engine speed under normal load,
change brands of gasoline or obtain a higher octane rated
fuel. If pinging or spark knock persists, see your local
Generac repair center.
colder 32°F warmer
SAE 10W30 SAE 30
Oil Filler Neck
Figure 2 — Adding Engine Oil
Fill to This Level
Figure 3 — Fuel Level

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OPERATING THE
GENERATOR
CAUTION! Never start or stop the engine with
electrical loads connected to the unit and with the
connected devices turned ON.
Starting the Engine
Disconnect all electrical loads from the generator. Use the
following start instructions:
• Be sure the spark plug wire is attached to the spark plug.
• Turn the fuel valve to the “Open” position (fully
clockwise) (Figure 4).
• Slide the choke lever to the “Choke” position (all the
way to the right) (Figure 5).
• Place the engine switch in the “On” position (Figure 6).
• Grasp starter grip and slowly pull the rope until you feel
some resistance, then pull the cord out with a rapid full
arm stroke. Let rope return slowly. Do Not let rope
“snap back” against the unit.
NOTE: If engine starts after 3 pulls, but fails to run for
more than 10 seconds, check for proper oil level in
crankcase. This unit is equipped with a Oil Alert System
(see page 7).
• Slide the choke lever left to the “Run” position as the
engine warms up.
NOTE: Under no load conditions, the engine speed may
vary slightly faster or slower until engine temperatures
stabilize.
CAUTION! Breathing Hazard! Never run engine
in enclosed poorly ventilated areas. Engine exhaust
contains carbon monoxide, an odorless and deadly
gas.
Connecting Electrical Loads
• Let engine stabilize and warm up for a few minutes after
starting.
•Do Not connect 240 Volt loads to 120 Volt receptacles.
•Do Not connect 3–phase loads to the generator.
•Do Not connect 50 Hz loads to the generator.
• Plug in and turn on the desired 120 Volt AC, single
phase, 60 Hertz electrical loads.
•DO NOT OVERLOAD THE GENERATOR. Add up
the rated watts (or amps) of all loads to be connected at
one time. This total should not be greater than the rated
wattage/amperage capacity of the generator. See “Don’t
Overload the Generator” on page 9.
Figure 5 — Choke Lever
Figure 4 — Fuel Valve in Open Position
Figure 6 — Engine Switch in On Position

Generac Portable Products G1000M Generator
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Stopping the Engine
• Unplug all electrical loads from the unit. Never start or
stop engine with electrical devices plugged in and turned
on.
• Let engine run at no–load for two minutes to stabilize
the internal temperatures.
• Move engine switch to the “Off” position.
• Turn the fuel valve to the “Close” position (fully
counterclockwise).
NOTE: In an emergency, stop the engine by moving the
engine switch to the “Off” position.
Oil Alert System
The Oil Alert System is designed to prevent engine damage
caused by an insufficient amount of oil in the crankcase.
Before the oil level in the crankcase can fall below a safe
limit, the Oil Alert System will automatically shut down the
engine (the engine switch will remain in the “On” position).
If the Oil Alert System shuts down the engine, add engine
oil.
Charging a Battery
WARNING! Storage batteries emit explosive gas
while charging that remains around a battery for a
long time after it has been charged. The slightest
spark can ignite the gas, causing an explosion that
can shatter the battery and cause blindness or
other injury.
WARNING! Do Not permit smoking, open
flame, sparks or any other source of heat around a
battery. Do Not use a lighter or other flame for
checking battery fluid levels. Wear protective
goggles, rubber apron and rubber gloves when
working around a battery. Battery electrolyte fluid is
an extremely caustic sulfuric acid solution that can
cause severe burns. Do Not permit fluid contact
with eyes, skin, clothing, etc. If spill occurs, flush
area with clear water immediately.
Your generator has the capability of recharging a discharged
12 Volt automotive or utility style storage battery. Do Not
use the unit to charge any 6 Volt batteries. Do Not use
the unit to crank an engine having a discharged battery.
To recharge 12 Volt batteries, proceed as follows:
• If necessary, clean battery posts or terminals.
• Check fluid level in all battery cells. If necessary, add
ONLY distilled water to cover separators in battery
cells. Do Not use tap water.
• If the battery is equipped with vent caps, make sure they
are installed and are tight.
• Connect battery charge cable connector plug to the
12 Volt DC panel receptacle.
• Connect battery charge cable clamp with red handle to
battery post or terminal indicated by Positive,POS or
(+) (Figure 7).
• Connect battery charge cable clamp with black handle
to battery post or terminal indicated by Negative,
NEG, or (–) (Figure 7).
• Start generator. Let the engine run while battery
recharges.
• When battery has charged, shut down engine (see
“Stopping The Engine”)
NOTE: Use an automotive hydrometer to test battery
state of charge and condition. Follow the hydrometer
manufacturer’s instructions carefully. Generally, a battery is
considered to be at 100% state of charge when specific
gravity of its fluid (as measured by hydrometer) is 1.260 or
higher.
Red Lead
To 12 Volt DC Panel
Receptacle
Positive Negative
Figure 7 — Battery Connections

Generac Portable Products G1000M Generator
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CONNECTOR PLUGS
120 Volt AC Receptacle
Each outlet socket is protected against overload by a
7.5 Amp push-to-reset circuit breaker. Use each receptacle
to operate 120 Volt AC, single phase, 60 Hz electrical loads
requiring up to 1,000 watts (1.0 kW) of power (Figure 8).
CAUTION! Although each receptacle is rated
for 120 Volts at 15 Amps (1,440 watts or 1.44 kW),
the generator is rated for a total of 1,000 watts.
Powering loads that exceed the wattage capacity of
the generator can damage it or cause serious
injuries. The total of loads powered through these
receptacles should not exceed 7.5 Amps.
12 Volt DC Accessory Jack
This receptacle allows you to recharge a 12 Volt
automotive or utility style storage battery with the battery
charge cable provided. Camping-style air pumps, lanterns,
fans, or other 12 Volt devices having a cigarette lighter-type
plug may also be powered by this outlet (Figure 9).
This receptacle can not recharge 6 Volt batteries and can
not be used to crank an engine having a discharged battery.
See “Charging a Battery” (page 7) before attempting to
recharge a battery.
EXTENSION CORDS
Use only high quality, well-insulated, extension cords with
the generator’s 120 Volt electrical receptacles.
Check the ratings of all extension cords before you use
them. Such cords should be rated for 125 Volt AC loads at
15 Amps (or greater) for most electrical devices. Some
devices, however, may not require this type of extension
cord. Check the owner’s manuals of those devices for their
recommendations.
Keep extension cords as short as possible, preferably less
than 15 feet long, to prevent voltage drop and possible
overheating of wires.
Figure 8 — 120 Volt AC, 15 Amp Duplex Receptacle
Figure 9 — 12 Volt DC Accessory Jack

Generac Portable Products G1000M Generator
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DON’T OVERLOAD THE
GENERATOR
Overloading a generator in excess of its rated wattage
capacity can result in damage to the generator and/or
connected electrical devices. Observe the following, to
prevent overloading the unit:
• Add up the total wattage of all electrical devices to be
connected at one time. This total should NOT be
greater than the generator’s wattage capacity.
• The rated wattage of lights can be taken from light bulbs.
The rated wattage of tools, appliances and motors can
usually be found on a data plate or decal affixed to the
device.
• If the appliance, tool or motor does not give wattage,
multiply 120 Volts times ampere rating to determine
watts (volts x amps = watts).
• Some electric motors, such as induction types, require
about three times more watts of power for starting than
for running. This surge of power lasts for only a few
seconds when starting such motors. Be sure you allow
for this high starting wattage when selecting electrical
devices to connect to your generator. First estimate the
watts needed to start the largest motor. Add to that
figure the running watts of all other connected loads.
• The wattage reference guide (Figure 10) is provided to
help you to determine how many items the generator
can operate at one time.
NOTE: It is important to observe that many of these
devices require more power than the generator can
produce.
Recreational/Home Uses
Tool/Appliance....................................................Watts
AM/FM clock radio.....................................................................50
Light bulb....................................................................................100
Fan................................................................................................200
20" color TV..............................................................................400
*Deep freezer............................................................................500
Personal computer and 15" monitor...................................800
*1/3 hp furnace fan blower.....................................................800
Microwave oven........................................................................800
*18 cu ft refrigerator...............................................................800
Sump pump..............................................................................1000
Electric skillet..........................................................................1250
*½ hp water well pump........................................................1400
*12,000 Btu window air conditioner.................................1400
Space heater............................................................................1800
Electric water heater.............................................................4000
Professional/Contractor Uses
Tool/Appliance....................................................Watts
*1/3 hp airless sprayer.............................................................600
3/8" hammer drill .....................................................................600
Variable speed Sawzall®..........................................................960
½" power drill.........................................................................1000
Quartz-halogen work light...................................................1000
Belt sander...............................................................................1200
7 ¼" circular saw ...................................................................1500
7 ¼" worm drive saw............................................................1600
*1½ hp air compressor ........................................................1800
*10" power miter saw...........................................................1800
6" bench grinder.....................................................................1800
*6" table planer.......................................................................1800
*10" table/radial arm saw .....................................................2000
Wire feed welder...................................................................2400
* allow 3 times listed watts for starting this device
Figure 10 — Wattage Reference Guide

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PRODUCT
SPECIFICATIONS
Generator Specifications
Rated Surge Watts . . . . . . . . . . . . . . . 1,000 Watts
Rated Running Watts . . . . . . . . . . . . . 900 Watts
Rated Maximum Current
At 120 Volts AC . . . . . . . . . . . . . .7.5 Amps
At 12 Volts DC . . . . . . . . . . . . . . .8.3 Amps
Phase . . . . . . . . . . . . . . . . . . . . . . . .Single Phase
Rated Frequency . . . . . . . . . . . . . . . .60 Hertz
Packaged Weight . . . . . . . . . . . . . . . .61.0 lbs.
Engine Specifications
Model . . . . . . . . . . . . . . . . . . . . . . . . Mitsubishi GM82
Rated Horsepower . . . . . . . . . . . . . . 2.4 at 4000 rpm
Displacement . . . . . . . . . . . . . . . . . . . 80cc
Spark Plug Type: . . . . . . . . . . . . . . . . . NGK BP6HS or
equivalent
Set Gap To: . . . . . . . . . . . . . . . . . . . . . 0.030inch (0.75mm)
Gasoline Capacity . . . . . . . . . . . . . . . 1.2 U.S. gallons (4.5 l)
GENERAL MAINTENANCE
RECOMMENDATIONS
The generator warranty does not cover items that have
been subjected to operator abuse or negligence. To receive
full value from the warranty, operator must maintain
generator as instructed in this manual.
Some adjustments will need to be made periodically to
properly maintain your generator.
All adjustments in this section should be made at least
once each season. Follow the requirements in the
“Maintenance Schedule” chart shown below in Figure 11.
NOTE: Once a year you should clean or replace the spark
plug and replace the air filter. A new spark plug and clean
air filter assure proper fuel-air mixture and help your
engine run better and last longer.
GENERATOR
MAINTENANCE
Generator maintenance consists of keeping the unit clean
and dry. Operate and store the unit in a clean dry
environment where it will not be exposed to excessive
dust, dirt, moisture or any corrosive vapors. Cooling air
slots in the generator must not become clogged with snow,
leaves or any other foreign material.
1 Clean more often under dirty or dusty conditions. Replace cleaner parts if very dirty.
2 Check every 10 hours or 3 months.
3 These items should be serviced by an authorized dealer, unless the owner has the proper tools and is mechanically
proficient.
Item Operation Each use First Month or
25 hours
Every 3 months
or 50 hours
Every 6 months
or 100 hours
Engine oil Check level X
Change X X
Air cleaner Check X
Clean X (1)
Spark arrester Check – Clean X (2,3)
Spark plug Check – Clean X
Valve clearance Check – Adjust X (3)
Fuel tank strainer Clean X (3)
Fuel line Check (Replace if
necessary)
Every 3 years (3)
Figure 11 – Maintenance Schedule

Generac Portable Products G1000M Generator
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Check the cleanliness of the generator frequently and clean
when dust, dirt, oil, moisture or other foreign substances
are visible on its exterior surface.
NOTE: Do Not use a garden hose to clean generator.
Water can enter engine fuel system and cause problems. In
addition, if water enters generator through cooling air
slots, some of the water will be retained in voids and
cracks of the rotor and stator winding insulation. Water
and dirt buildup on the generator internal windings will
eventually decrease the insulation resistance of these
windings.
To Clean the Generator
• Use a damp cloth to wipe exterior surfaces clean.
• Soft, bristle brush may be used to loosen caked on dirt
or oil.
CAUTION! Never insert any object or tool
through the air cooling slots, even if the engine is
not running.
• A vacuum cleaner may be used to pick up loose dirt and
debris.
• Low pressure air (not to exceed 25 psi) may be used to
blow away dirt. Inspect cooling air slots and opening on
generator. These openings must be kept clean and
unobstructed.
DANGER! When working on the generator
always disconnect spark plug wire from spark plug
and keep it away from spark plug.
ENGINE MAINTENANCE
Checking Oil Level
Oil level should be checked prior to each use or at least
every 5 hours of operation. Keep oil level maintained.
Changing Engine Oil
Change the oil after the first month of operation, then
every 25 hours. If you are using your generator under
extremely dirty or dusty conditions, or in extremely hot
weather, change the oil more often.
Change the oil while the engine is still warm from running,
as follows:
• Remove the oil fill cover and clean area around oil drain
plug (Figure 12).
• Remove oil drain plug, sealing washer, and oil filler cap.
Drain oil completely into a suitable container.
• Install oil drain plug and sealing washer. Tighten securely.
• Refill with recommended oil and check the level. See
page 5 for oil recommendations.
• Wipe up any spilled oil.
CAUTION! Avoid prolonged or repeated skin
contact with used motor oil. Used motor oil has
been shown to cause skin cancer in certain
laboratory animals. Thoroughly wash exposed areas
with soap and water. KEEP OUT OF REACH OF
CHILDREN.
DON'T POLLUTE. CONSERVE RESOURCES.
RETURN USED OIL TO COLLECTION CENTERS.
• Replace oil fill cover.
Clean/Replace Spark Plug
Check and clean the spark plug every 50 hours of
operation or every three months, whichever comes first.
This will help your engine to start easier and run better.
• Remove spark plug access cover. Remove spark plug cap.
• Clean the area around the spark plug.
• Remove and inspect the spark plug.
• Replace the spark plug if electrodes are pitted or burned
or the porcelain is cracked. Use recommended plug for
replacement.
• Check electrode gap with wire feeler gauge and set spark
plug gap between 0.028 and 0.031 inch (0.7 to 0.8 mm) if
necessary (Figure 13).
Figure 12 — Oil Drain Plug
Oil Drain Plug

• Reinstall spark plug.
Service Air Cleaner
Your engine will not run properly and may be damaged if
you run it using a dirty air filter element.
Check the air filter every use and clean or replace the
paper air filter element every 50 hours of operation or
every three months, whichever comes first. Clean or
replace more often if operating under dusty or dirty
conditions.
To clean or replace air filter element:
• Loosen the air cleaner cover screws, remove the air
cleaner cover, and remove the element (see item
number 4, exploded view on page 20.
• Wipe clean the inside of the filter housing and cover
thoroughly.
• Wash the element in a solution of household detergent
and warm water, then rinse thoroughly. Or wash in
nonflammable or high flash point solvent. Allow the
element to dry thoroughly.
• Soak the element in clean engine oil and squeeze out the
excess oil. Do Not twist. The engine will smoke during
initial start-up if too much oil is left in the element.
NOTE: If you need to order a new air filter element,
please call 1-800-270-1408.
• Reinstall the air cleaner element and the cover. Hand
tighten the air cleaner cover screws.
Clean Spark Arrester Screen
The engine muffler is equipped with a removable spark
arrester screen. Inspect and clean the screen every
10 hours of operation or every three months, as shown in
Figure 13A:
• Loosen the screw on the muffler tail pipe and remove
the spark arrester screen.
• Use a brass or stiff-bristle brush to remove carbon
deposits from the spark arrester surface.
• Inspect the spark arrester for breaks or tears and
replace it if necessary.
NOTE: If you need to order a new spark arrester, please
call 1-800-270-1408.
• Install the clean screen in the reverse order of removal.
NOTE: If you use your generator on any forest-covered,
brush-covered or grass-covered unimproved land, it must
have a spark arrester installed. The spark arrester must be
maintained in good condition by the owner/operator.
STORAGE INSTRUCTIONS
Transporting and Storage
When transporting the generator, turn the engine switch
to “Off” and the fuel valve to “Close”. Keep the generator
level to prevent fuel spillage.
WARNING! Contact with a hot engine or
exhaust system can cause serious burns or fires. Let
the engine cool before transporting or storing the
generator.
Take care to not drop or strike the generator when
transporting. Do Not place heavy objects on the
generator.
The generator should be started at least once every seven
days and allowed to run at least 30 minutes. If this cannot
be done and you must store the unit for more than 30 days,
use the following guidelines to prepare it for storage.
Generac Portable Products G1000M Generator
12
Figure 13 — Service Spark Plug
Spark Arrester
Screen
Muffler Tail Pipe
Spark Arrester
Attachment Screw
Figure 13A – Service Spark Arrester Screen

Long Term Storage Instructions
WARNING! Never store engine with fuel in
tank indoors or in enclosed, poorly ventilated areas
where fumes may reach an open flame, spark or
pilot light as on a furnace, water heater, clothes
dryer or other gas appliance.
Be sure the storage area is free from excessive
humidity and dust.
One Month to One Year
Drain the carburetor float bowl (see following section) and
fuel tank into a suitable container. After removal from
storage, fill with fresh gasoline before starting.
More than One Year
It is important to prevent gum deposits from forming in
essential fuel system parts such as the carburetor, fuel filter,
fuel hose or tank during storage. Also, experience indicates
that alcohol-blended fuels (called gasohol, ethanol or
methanol) can attract moisture, which leads to separation
and formation of acids during storage. Acidic gas can
damage the fuel system of an engine while in storage.
To avoid engine problems, the fuel system should be
emptied before storage of 30 days or longer. Follow these
instructions:
Protect Fuel System
WARNING! Drain fuel into approved container
outdoors, away from open flame. Be sure engine is
cool. Do Not smoke.
• Drain carburetor float bowl and fuel tank into a suitable
container by loosening the drain screw (Figure 14).
• Retighten drain screw before refueling.
Change Oil
While engine is still warm, change oil as described on
page 11. Refill with recommended grade.
Oil Cylinder Bore
• Remove spark plug and pour about one tablespoon of
clean engine oil into the cylinder.
CAUTION! Avoid spray from spark plug hole
when cranking engine slowly.
• Cover spark plug hole with rag. Crank slowly several
times to distribute oil.
• Install spark plug. Do Not connect spark plug wire.
• Slowly pull the starter grip until resistance is felt. At this
point, the piston is coming up on its compression stroke
and both the intake and exhaust valves are closed.
Storing the engine in this position will help to protect it
from internal corrosion.
Generator
• Clean the generator as outlined on page 11 (“To Clean
the Generator”).
• Check that cooling air slots and openings on generator
are open and unobstructed.
Other Storage Tips
•Do Not store gasoline from one season to another.
• Replace the gasoline can if it starts to rust. Rust and/or
dirt in gasoline will cause problems.
• If possible, store your unit indoors. BE SURE TO
EMPTY THE FUEL TANK.
• Cover your unit with a suitable protective cover that
does not retain moisture.
IMPORTANT: Never cover your generator while engine
and exhaust area are warm.
• Store generator in clean, dry area.
Generac Portable Products G1000M Generator
13
Carburetor Fuel
Drain Screw
Drain Screw
Access Hole
Figure 14 – Drain Fuel From Carburetor

Generac Portable Products G1000M Generator
14
TROUBLESHOOTING
Problem Cause Correction
Engine is running, but
no AC or DC
output is available.
1. One of the circuit breakers is open.
2. Fault in generator.
3. Poor connection or defective cord set.
4. Connected device is bad.
1. Reset circuit breaker.
2. Contact Generac service facility.
3. Check and repair.
4. Connect another device that is in
good condition.
Engine runs good at
no-load but “bogs
down" when loads
are connected.
1. Short circuit in a connected load.
2. Engine speed is too slow.
3. Generator is overloaded.
4. Shorted generator circuit.
1. Disconnect shorted electrical load.
2. Contact Generac service facility.
3. See “Don't Overload the Generator”
on page 9.
4. Contact Generac service facility.
Engine will not start;
or starts and runs
rough.
1. Engine switch set to “Off”.
2. Dirty air cleaner.
3. Out of gasoline.
4. Stale gasoline.
5. Spark plug wire not connected to spark
plug.
6. Bad spark plug.
7. Water in gasoline.
8. Overchoked or flooded.
9. Excessively rich fuel mixture.
10. Intake valve stuck open or closed.
11. Engine has lost compression.
1. Set switch to “On”.
2. Clean or replace air cleaner.
3. Fill fuel tank.
4. Drain gas tank and carburetor; fill
with fresh fuel.
5. Connect wire to spark plug.
6. Replace spark plug.
7. Drain gas tank and carburetor; fill
with fresh fuel.
8. Wait 5 minutes and re-crank engine.
9. Contact Generac service facility.
10. Contact Generac service facility.
11. Contact Generac service facility.
Engine shuts down
when running.
Out of gasoline. Fill fuel tank.
Engine lacks power. 1. Load is too high.
2. Dirty air filter.
1. See “Don't Overload the Generator”
on page 9.
2. Replace air filter.
Engine “hunts” or
falters.
Carburetor is running too rich or too lean. Contact Generac service facility.

Generac Portable Products G1000M Generator
15
WIRING DIAGRAM

Generac Portable Products G1000M Generator
16
EXPLODED VIEW AND PARTS LIST – MAIN UNIT
Item Part # Qty Description
1 NSP 1 ENG, MITSUB, 2.4HP
2 187378 1 ROTOR
3 187411 1 BRG
4 187379 1 STATOR
5 187430 1 LEAD, GREEN
6 187409 1 BUSHING, LEAD WIRE, G790B
7 187381 1 RBC, 1K
8 187399 3 SCREW, SELF TAP, M6-12
9 187382 1 FAN, COOLING
10 187388 1 BOLT, RTR
11 187389 3 BOLT, STATOR
12 187405 1 INSLTN, HEAT SEALED, #1
13 187384 1 MFFLR, SEALED
14 187407 1 INSLTN, HEAT SEALED, #2
15 187403 1 DUCT, AIR
Item Part # Qty Description
16 187392 2 PHMS, M6-1.0, W/L/FW
17 187383 1 BASE, GEN
18 187390 4 BOLT, FLNG, M6-1.0 X 10
19 187385 4 MNT, VIBR
20 187427 4 HHCS, FLNG, M8-1.25 X 12
21 187424 1 NUT, WING, M5 X 0.8
22 187423 1 NUT, M5 X 0.8
23 187419 2 WSHR, LOCK
24 187420 2 WSHR, FLAT
25 187401 2 NUT, M8-1.25, FLANGE
26 187415 1 PHMS, M5-0.8 X 20
27 187413 2 CNNCTR
28 187434 4 HHCS, FLNG
29 187431 1 STND, ENG

Generac Portable Products G1000M Generator
17
Item Part # Qty Description
1 187436 1 CAP, FUEL
2 187439 1 PACKING, TANK
3 187438 1 FLTR, FUEL
4 187769 3 U-PACKING
5 187437 1 TANK, FUEL, 4.5L
6 187766 1 DECAL, CHOKE
7 187756 4 BOLT, COVER (M5-16)
8 187875 1 HSG, GEN, MFFLR
9 187807 1 DECAL, WARNING
10 187772 1 COVER, SPARK PLUG
11 187757 5 BOLT, COVER (M6-16)
12 187760 11 PHMS, M4-12 W/FW
13 187435 1 CVR, MFFLR, GEN
14 187775 3 BOLT, MFFLR CVR (M6-16)
15 187768 1 DECAL CAUTION HOT
16 187774 4 BOLT, COVER (M6-20)
17 187761 8 NUT, M4X0.6 W/FW
18 187463 1 INSLTN, MFFLR
19 187874 1 HSG, GEN
20 NSP 1 DECAL, EMISSIONS
21 187457 1 CONDENSER, 300V
22 187765 1 DECAL, CAUTION FUEL
23 187759 2 BOLT, COVER (M5-10)
Item Part # Qty Description
24 187462 1 DIODE, BRIDGE
25 187881 1 BOTTLE, OIL
26 20566 1 DECAL, 1-800
27 187773 1 COVER, OIL FILL
28 187460 1 CB, DC
29 187454 1 CB, 8A, 125V
30 187873 1 OUTLET, ACCESSORY DC
31 187450 1 SWITCH, ENG, ON/OFF
32 187812 1 CPNL
33 187456 1 RECPTCL, 15A, 125V
34 187763 1 DECAL, CAUTION OIL
35 187876 1 CABLE, BATTERY CHARGE
36 187340 1 DECAL, MODEL
37 187764 1 DECAL, FUEL SHUTOFF
38 187447 1 INSLTN, HTSHLD, TANK #1
39 187448 1 INSLTN, HTSHLD, TANK #2
40 187442 2 BRKT, TANK, FUEL
41 187758 1 BRKT, FUEL COCK
42 187443 1 COCK, FUEL
43 187770 1 PHMS, M5-10 W/FW
44 187579 1 CLIP, FUEL HOSE
45 187440 1 FLTR, FUEL
46 187578 1 HOSE, FUEL
EXPLODED VIEW AND PARTS LIST – MAIN UNIT

Generac Portable Products G1000M Generator
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EXPLODED VIEW AND PARTS LIST – ENGINE
Cylinder Block, Cylinder Head
Item Part # Qty Description
1 187404 1 ASSY, CYL HEAD
2 187406 2 TPPT, CYL HEAD
3 187408 2 VLV, EXH
4 187410 2 SPRNG, VLV
5 187412 2 RTNR, VLV SPG
6 187414 2 ROD, PUSH
7 187416 1 ASSY, RCKR, ARM
8 187417 2 NUT, CYL HEAD
9 187418 2 SCRW, ADJST
10 187421 1 PLT, CYL HEAD
Item Part # Qty Description
11 187422 1 SEAL, VLV STEM
12 187423 4 NUT, M5 X 0.8
13 187426 4 BOLT, FLNG
14 187428 2 PIN, DWL
15 187429 1 GSKT, HEAD
16 187468 1 CVR, VALVE
17 187470 4 BOLT, VALVE CVR
18 187472 1 GSKT, VALVE CVR
19 187569 2 BOLT, STUD
Item Part # Qty Description
1 187380 1 BLOCK, CYL
2 187386 1 ASSY, GOV, GEAR
3 187387 1 SLIDER, GOV
4 187391 1 SHFT, GOV
5 187393 2 PLUG, DRAIN
6 187394 2 SEAL, OIL
7 187395 1 BRG, BALL
8 187400 1 WSHR, CYLBLOCK
9 187402 2 GSKT, CYLBLOCK

Generac Portable Products G1000M Generator
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EXPLODED VIEW AND PARTS LIST – ENGINE
Crankcase Cover, Crankshaft/Camshaft
Item Part # Qty Description
1 187394 2 SEAL, OIL
2 187473 1 CVR, CRANKCASE
3 187474 1 DIPSTICK, OIL
4 187475 1 O-RING, DIPSTICK
5 187477 1 BRG, PTO
6 187478 6 BOLT, CRANKCASE CVR
7 187428 2 PIN, DWL
8 187479 1 GSKT, CRANKCASE CVR
Item Part # Qty Description
1 187481 1 ASSY, CRNKSHFT
2 187484 1 GEAR, CRNKSHFT
3 187486 2 KEY, WOODRFF
4 187487 1 GEAR, CRNKSHFT
6 187488 1 ASSY, CAMSHAFT
7 187489 1 PIN, CMPR REL
8 187490 1 RNG, SNP, CMPRSSN
REL

Generac Portable Products G1000M Generator
20
EXPLODED VIEW AND PARTS LIST – ENGINE
Piston/Rod, Magneto/Flywheel, Air Cleaner
Item Part # Qty Description
1 187526 1 ROD, CNNCTNG, STD
1 187527 1 ROD, CNNCTNG, US.25
1 187528 1 ROD, CNNCTNG, US.50
2 187529 2 BOLT, CNNCTNG ROD
3 187530 1 ASSY, PSTN, STD
3 187531 1 ASSY, PSTN, OS.25
3 187532 1 ASSY, PSTN, OS.50
4 187533 1 PIN, PISTON
5 187534 1 SET, RING, PSTN, STD
5 187535 1 SET, RING, PSTN, OS.25
5 187537 1 SET, RING, PSTN, OS.50
6 187539 2 CLIP, SPRING, PSTN PIN
Item Part # Qty Description
1 187540 1 FLYWHL
2 187541 1 COIL, IGNITION
3 187543 1 FAN
4 187544 1 CLIP, MAGNETO
5 187545 2 BOLT, MAGNETO
6 187546 1 NUT
Item Part # Qty Description
1 187492 1 HSNG, AIR CLNR
2 187494 1 CVR, AIR CLNR
3 187496 1 SPRT, AIR CLNR
4 187497 1 ELEMENT, AIR CLNR
5 187498 1 BRTHR, AIR CLNR
6 187500 2 STUD, AIR CLNR
7 187501 2 SCREW, AIR CLNR CVR
8 187503 2 NUT, AIR CLNR CVR
9 187504 1 GSKT, CARB
10 187576 1 DECAL, CHOKE