U.S. GENERAL THUNDERBOLT 3708 (01) PDF MANUAL

U.S. GENERAL THUNDERBOLT 3708 (01) PDF SUMMARY:

What are the general rules for using the generator?

1. Choke Lever
2. Air Cleaner
3. Starter Handle
4. ON/OFF Switch
5. Engine serial number
6. Oil Drain plug
7. Oil Filler Cap
8. Ground Terminal
9. AC Circuit Breaker
10. AC Receptacles
11. Muffler
12. Spark Plug Cap
13. Fuel Tank Cap

Record the engine and frame serial numbers for your future reference. Refer to these serial numbers when ordering parts, and when making technical inquiry.

What should I do when transporting or storing the generator?

When transporting the generator, turn the ON/OFF switch and the fuel switch OFF. Keep the generator level to prevent fuel spillsge. Fuel vapor or spilled fuel may ignite.

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 not to drop or strike the generator when transporting. Do not place heavy objects on the generator.

Before storing the unit for an extended period:

1. Be sure the storage area is free of excessive humidity and dust.
2. Service according to the table below:

WARNING

Gasoline is extremely flammable and is explosive under certain conditions Perform this task in a well ventilated area with the engine stopped. Do not smoke or allow flames. or sparks in the area during this procedure.

How do I drain the carburetor?

Drain the carburetor by loosening the drain screw. Drain the gasoline into a suitable container.

How do I prepare the generator for storage?

1. Drain the carburetor.
2. Change the engine oil.
3. Remove the spark plug, and pour about a tablespoon of clean engine oil into the cylinder. Crank the engine several revolutions to distribute the oil, then reinstall the spark plug.
4. 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 is from internal corrosion.

NOTE:

Engine oil is a major factor affecting engine performance and service life. This unit is shipped without oil in the engine crankcase.

What should I do before starting the engine?

ADD ENGINE OIL BEFORE STARTING ENGINE! Check the oil level BEFORE EACH USE with the generator on a level surface with the engine stopped.

What kind of motor oil should I use?

Use McCulloch 4-stroke oil, or an equivalent high detergent, premium quality motor oil certified to meet or exceed U.S. automobile manufacturer’s requirements for Service Classification SG SF/CC CD. Motor oils classified SG SF/CC CD will show this designation on the container. Do not use special oil additives.

• a). SG • SF/CC • CD SINGLE VISCOSITY
• b). SG • SF/CC • CD MULTI VISCOSITY

What is the recommended oil viscosity?

SAE 10W-30 is recommended for general, all-temperature use. Other viscosities shown in the chart may be used when the average temperature in your area is within the indicated range.

How do I check the oil level?

1. Remove the oil filler cap (A) and wipe the dipstick clean. (See Fig. 3-1 B)
2. Check the oil level (B) by inserting the dipstick into the filler neck without screwing it in. (See Fig. 3-1C)
3. If the level Is low, fill to the top of the oil filler neck with the recommended oil.

What are the fuel recommendations?

1. Check the fuel level.
2. Refill the tank if the fuel level is low. Do not fill to top: Leave some space for fuel expansion.

WARNING

Gasoline is extremely flammable and is explosive under certain conditions. Refuel in a well-ventilated area with the engine stopped. Do not smoke or allow flames or sparks in the area where the engine ts refuled or where gasoline is stored.

What precautions should I take when refueling?

• Do not overfill the fuel tank (there should be no fuel in the filler neck).
• After refueling, make sure the tank cap is closed properly and securely.
• Be careful not to spill fuel when refueling. Spilled fuel or fuel vapor may ignite. If any fuel is spilled, make sure the area is dry before starting the engine.
• Avoid repeated or prolonged contact with skin or breathing of vapor.
• KEEP OUT OF REACH OF CHILDREN.

Fuel tank capacity: 5.0 gal. (19.0L)

How should I dispose of used motor oil?

Pleas dispose of used motor oil in a manner that is compatible with the environment. We suggest you take it in a sealed container to your local service station or recycling center for reclamation. Do not throw it in the trash or pour it on the ground.

How do I service the air filter?

A dirty air cleaner will restrict air flow to the carburetor. To prevent carburetor malfunction, service the air cleaner regularly. Service more frequently when operating the generator in extremely dusty areas.

WARNING

Using gasoline or flammable solvent to clean the filter element can cause a fire or explosion. Use only soapy water or nonflammable solvent.

NOTE:

Never run the generator without the air filter. Rapid engine wear will result.

What are the steps for servicing the air filter?

1. Unsnap the air filter cover clips (A), remove the air cover (B), and remove the element.
2. Wash the element in a solution of household detergent and warm water, then rinse thoroughly; or wash in non-flammable or high flash point solvent. Allow the element to dry thoroughly.
3. Soak the element in clean engine oil and squeeze out the excess oil. The engine will smoke during initial start-up it too much oil is left in the element.
4. Reinstall the air filter element and the cover.

How do I clean the fuel sediment cup?

The sediment cup prevents dirt or water which may be in the fuel tank from entering the carburetor. If the engine has not been run for a long time, the sediment cup should be cleaned.

What are the steps for cleaning the fuel sediment cup?

1. Turn the fuel switch the OFF position. Remove the sediment cup, O-ring, and filter.
2. Clean the sediment cup, O-ring, and filter in nonflammable or high flash point solvent.
3. Reinstall the filter, O-ring, and sediment cup.
4. Turn the fuel valve ON and check for leaks.

How do I service the spark plug?

To ensure proper engine operation, the spark plug must be properly gapped and free of deposits. If the engine has been running, the muffler will be very hot. Be careful not to touch the muffler.

What are the steps for servicing the spark plug?

1. Remove the spark plug cap.
2. Clean any dirt from around the spark plug base.
3. Use the wrench supplied in the tool kit to remove the spark plug.
4. Visually inspect the spark plug. Discard it if the insulator is cracked or chipped. Clean the spark plug with a wire brush if it is fouled.
5. Using a feeler gauge, measure the gap between the center electrode and the side electrode.
6. Check that the spark plug washer is in good condition, and thread the spark plug in by hand to prevent cross-threading.
7. After the spark plug is seated, tighten with a spark plug wrench to compress the washer. If installing a new spark plug, tighten 1/2 turn after the spark plug seats to compress the washer. If reinstalling a used spark plug, tighten 1/8~1/4 turn after the spark plug seats to compress the washer.

NOTE:

The spark plug must be securely tightened. An improperly tightened spark plug can become very hot and could damage the engine. Never use spark plugs which have an improper heat range. Use only the recommended spark plugs or their equivalent.

What should the gap between the center electrode and the side electrode on the spark plug be?

The gap should be: 0.70-0.80 mm (0.028-0.031")

What should I do if the AC circuit breaker needs replacement?

If AC circuit breaker require replacement they must be replaced with a circuit breaker having identical ratings and performance characteristics. Contact your nearest McCulloch Authorized Service dealer for replacement service.

What are the engine operations?

How do I use the ON/OFF SWITCH?

To start and stop the engine. (See Fig. 4-1A)

Switch position:

• OFF: To stop the engine. Key can be removed/inserted.
• ON: To reun the engine after starting.

How do I use the RECOIL STARTER?

To start the engine, pull the starter grip lightly until resistance is felt, then pull briskly.

NOTE:

Do not allow the starter to snap back against the engine. Return it gently to prevent damage to the starter.

How do I use the FUEL SWITCH?

The fuel switch is located between the fuel tank and carburetor. When the switch level is in to ON position, fuel is allowed to flow from the fuel tank to the carburetor. Be sure to return the lever to OFF after stopping the engine. (See Fig. 4-1B)

How do I use the CHOKE LEVER?

The choke is used to provide an enriched fuel mixture when starting a cold engine. It can be opened and closed by operating the choke lever manually. Move the lever out toward SLOW to enrich the mixture. (See Fig. 4-1 B)

How does the OIL ALERT SYSTEM work?

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).

What are the generator operations?

How does the CIRCUIT BREAKER work?

The circuit breaker (A) will automatically switch OFF if there is a short circuit or a significant overload of the generator at the receptacle. If the circuit breaker is switched OFF automatically, check that the appliance is working properly and does not exceed the rated load capacity of the circuit before switching the circuit breaker ON again. (See Fig. 4-2A)

What is the GROUND TERMINAL?

The generator ground terminal is connected to the frame of the generater, the metal non-current carrying parts of the generator, and the ground terminals of each receptacle. (See Fig. 4-2B)

How do I connect the generator to a building’s electrical system?

Connections for standby power to a building’s electrical system must be made by a qualified electrician. The connection must isolate the generator power from utility power, and must comply with all applicable laws and electrical codes.

CAUTION

Improper connections to a building’s electrical system can allow electrical current from the generator to backfeed into the utility lines. Such backfeed may electrocute utility company workers or others who contact the lines during a power outage. Consult the utility company or a qualified electrician.

CAUTION

Improper connections to a building’s electrical system can allow electrical current from the utility company to backfeed into the generator. When utility power is restored, the generator may explode, burn, or cause fires in the building’s electrical system.

In some areas, generators are required by law to be registered with local utility companies. Check local regulations for proper registration and use procedures.

What are the generator ground circuits?

McCulloch portable generators have a system ground that connects generator frame components to the ground terminals in the AC output receptacles. The system ground is not connected to the AC neutral wire.

Local regulations, codes or laws may require that the ground system be connected to the AC neutral wire. If the generator is tested by a receptacle tester, it will not show the same ground circuit condition as for a home receptacle.

If local regulations, codes, or laws require the system ground to be connected to the AC neutral wire, consult a qualified electrician or electrical inspector. Provide him with the electrical wiring diagram in this manual.

The ground terminal can be used to earth the generator or bond the frame of the generator to the frame of a vehicle, but only if it is required by local law or electrical code. Before using the ground terminal consult a qualified electrician or electrical inspector for regulations in your area.

What are the AC applications?

Before connecting an appliance or power cord to the generator:

• Make sure that it is in good working order. Faulty appliances or power cords can create a potential for electrical shock.
• If an appliance begins to operate abnormally, becomes sluggish or stops suddenly, turn it off immediately. Disconnect the appliance, and determine whether the problem is the appliance, or if the rated load capacity of the generator has been exceeded.
• Make sure that the electrical rating of the tooi or appliance does not exceed that of the generator, Never exceed the maximum power rating of the generator. Power levels between rated and maximum may be used for no more than 30 minutes.

NOTICE:

Substantial overloading will open the circuit breaker. Exceeding the time limit for maximum power operation or slightly overloading the generator may not switch the circuit breaker OFF, but will shorten the service life of the generator. Limit operation requiring maximum power to 30 minutes. Maximum power is: See chart below. For continuous operation, do not exceed the rated power. Rated power is: See chart below.

MODEL

3708
Rated Frequancy (Hz) 60
Maxumum (KVA) 5.7
Rated Power (KVA) 5.1

In either case, the total power requirements (VA) of all appliances connected must be considered. Appliance and power tool manufacturers usually list rating information near the model number of serial number.

How do I operate the AC?

1. Start the engine.
2. Switch ON the AC circuit breaker.
3. Plug in the appliance. Most motorized appliances require more than their rated wattage for start up. Do not exceed the current limit specified for receptacle.

II an overloaded circuit causes the AC circuit breaker to switch OFF, reduce the electrical load on the circuit, wait a few minutes and then reset the circuit breaker.

How do I start the engine?

1. Make sure that disconnect all electrical loads from panel receptacles.
2. Turn the fuel switch to the ON position.
3. The automatic choke will be closed if the engine is cold. If you want to operate the choke manually, move the choke lever out to the CLOSED position.
4. Start the engine

How do I start the engine with the recoil starter?

• Turn the ON/OFF switch to the ON position.
• Pull the starter grip lightly until resistance is felt, then pull briskly.

NOTE:

• Do not allow the starter grip to snap back against the engine.
• NOTE: Return it gently to prevent damage to the starter or housing.

How do I operate the choke?

If you have manually closed the choke, move it to the OPEN position as the engine warms up.

How do I stop the engine in an emergency?

1. To stop the engine in an emergency, turn the engine switch to the OFF position.

How do I stop the engine in normal use?

1. Turn the AC circuit breaker to the OFF position.
2. Disconnect all electrical loads from panel receptacles.
3. Turn the engine switch to the OFF position.
4. Turn the fuel switch to the OFF position.

When is periodic maintenance and adjustment required?

Periodic maintenance and adjustment is necessary to keep the generator in good operating condition. Perform the service and inspection at the intervals shown in the Maintenance schedule below.

WARNING

Sehaust gas contains poisonous carbon monoxide. Shut off the engine before performing any maintenance. If the engine must be run, make sure the area is well ventilated.

NOTE:

Use only genuine McCulloch parts or their equivalent for quality may damage the generator.

REGULAR SERVICE PERIOD – Performed at every indicated Each Firstmonlhor Every 3 months Every 6 months Every Year or month or operating hour interva, whichever comes first. use 20Hrs. (3) or 50 Hrs. (3) or100Hrs. (3) 300Hrs. (3)

ITEM
ENGINE OIL	Check Level 0	Change 0
AIR FILTER	Check 0		Change 0 (1)
SEDIMENT CUP		Clean 0
SPARK PLUG		Check-Clean 0
SPARK ARRESTER			Clean 0
VALVE CLEARANCE				O (2)
FUEL TANK AND STRAINER				o (2)
FUEL LINE				Check (Replace if necessary) Every 2 years (2)

(1) Service more frequently when used in dusty areas.

(2) These items should be serviced by an authorized McCulloch generator dealer, unless the owner has the proper tools and is mechanically proficient. See the McCullcoh Shop Manual.

(3) For professional commercial use, log hours of operation to operation to determine proper maintenance intervals.

How do I change the engine oil?

Drain the oil while the engine is warm to assure rapid and complete draining.

What are the steps for changing the engine oil?

1. Remove the drain plug and oil filter cap and drain the oil.
2. Reinstall the drain plug and oil filter cap. Tighten the plug securely
3. Refill with the recommended oil and check the level.
4. Install oil filter cap. Oil Capacity: Oil Capacity (L) 1.1

CAUTION

Used motor oil may cause skin cancer if repeatedly left in contact with the skin for prolonged periods. Although this is unlikely unless you handle used oil on a daily basis, it is still advisable to thoroughly wash your hands with soap and water as soon as possible after handling used oil.

What kind of gasoline is recommended?

1. Use only clean, fresh, unleaded gasoline.
2. We recommend unleaded gasoline because it produces fewer engine and spark plug deposits and extends exhaust system life.
3. Never use stale or contaminated gasoline or oil/gasoline mixture. Avoid getting dirt or water in the fuel tank.
4. Occasionally you may hear light “spark knock” or pinging" (metallic rapping noise) while operating under heavy loads. This is no cause for concern.
5. If spark knock or pinging occurs at a steady engine speed, under normal load, change brands of gasoline. If spark knock or pinging persists, see an authorized McCulloch generator dealer.

When transporting the generator, what should I do?

When transporting the generator, turn the ON/OFF switch and the fuel switch OFF. Keep the generator level to prevent fuel spillsge. Fuel vapor or spilled fuel may ignite.

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.

What precautions should I take when transporting the generator?

Take care not to drop or strike the generator when transporting. Do not place heavy objects on the generator.

Before storing the unit for an extended period:

1. Be sure the storage area is free of excessive humidity and dust.
2. Service according lo the table below:

STORAGE TIME RECOMMENDED SERVICE PROCEDURE TO PREVENT HARD STARTING

Less than 1 month	No preparation required
1 to 2 months	Fill with fresh gasoline and add gasoline conditioner*./ Drain the carburetor float bowl. I Drain the fuel sediment cup.
3 to 6 months	Fill with fresh gasoline and add gasoline conditioner*. / Drain the carburetor float bowl. / Drain the fuel sediment cup. / Remove the spark plug. Put a tablespoon of engine oil into the cylinder. Turn the engine slowly with the pull rope to distribute the oil. Reinstall the spark plug. / Change the engine oil. / After removal from storage, drain the stored gasoline into a suitable container, and fill with fresh gasoline before staring.
1 Year or more	Fill with fresh gasoline and add gasoline conditioner*. / Drain the carburetor float bowl. / Drain the fuel sediment cup. / Remove the spark plug. Put a tablespoon of engine oil into the cylinder. Turn the engine slowly with the pull rope to distribute the oil. Reinstall the spark plug. / Change the engine oil. / After removal from storage, drain the stored gasoline into a suitable container, and fill with fresh gasoline before staring.

What do the safety labels warn you about?

These labels warn you of potential hazards that can cause serious injury. Read them carefully. If a label comes off or becomes hard to read, contact your McCulloch.

CAUTION

Do not connect to a building’s electrical system unless an isolation switch has been installed by a qualified electrician.

CAUTION

Do not use a generator-or electrical appliance in wet, conditions, such as rain or snow, or near a pool or sprinkler sys­ tem, or when your hands are wet, could result in electrocution. Keep the generator dry.

How are McCulloch generators designed to operate?

McCulloch generators are designed to give safe and dependable service if operated according to instructions. Read and understand this user manual before operating your generator. You can help prevent accidents by being familiar with your generator’s controls, and by observing safety operating procedures.

What are the operator responsibilities?

1. Know how to stop the generator quickly in case of emergency.
2. Understand the use of all generator controls, output receptacles, and connections.
3. Be sure that anyone who operates the generator receives proper instruction. Do not let children operate the generator without parental supervision. Always keep children away from the generator.

What are the carbon monoxide hazards?

1. Exhaust contains poisonous carbon monoxide, a colorless and odorless gas. Breathing exhaust can cause loss of con­ sciousness and may lead to death.
2. If you run the generator in an area that is confined, or even partially enclosed, the air you breathe could contain a dan- gerous amount of exhaust gas. To keep exhaust gas from building up, provide adequate ventilation.

What are the electric shock hazards?

1. The generator produces enough electric power to cause a serious shock or electrocution if misused.
2. Using a generator or electrical appliance in wet conditions, such as rain or snow, or near a pool or sprinkler system, or when your hands are wet, could result in electrocution. Keep the generator dry.
3. If the generator is stored outdoors, unprotected from the weather, check all electrical components on the control panel, before each use. Moisture or ice can cause a malfunction or short circuit in electrical components which could result in electrocution.
4. Do not connect to a building’s electrical system unless an isolation switch has been installed by a qualified electrician.

What are the fire and burn hazards?

1. The exhaust system gets hot enough to ignite some materials.

• Keep the generator at least 1 meter (3 feet) away from buildings and other equipment during operation.
• Do not enclose the generator in any structure.
• Keep flammable materials away from the generator.

2. The muffler becomes very hot during operation and remains hot for a while after stopping the engine. Be careful not to touch the muffler while it is hot. Let the engine cool before storing the generator indoors.
3. Gasoline is extremely flammable and is explosive under certain conditions. Do not smoke or allow flames or sparks where the generator is refueled or where gasoline is stored. Refuel in a well-ventilated area with the engine stopped.
4. Fuel vapors are extremely flammable and may ignite after the engine has started. Make sure that any spilled fuel has been wiped up before starting the generator.

What do I do if the unit won’t start or starts but will not run?

• Incorrect starting procedures. Follow instructions in the User Manual.
• Incorrect carburetor mixture adjustment setting. Have carburetor adjusted by an Authorized Service Center.
• Fouled spark plug Clean / gap or replace plug.
• Fuel filter plugged. Replace fuel filter.

What do I do if the unit starts, but engine has low power?

• Incorrect lever position on choke. Move to OPEN position.
• Dirty spark arrester screen. Replace spark arrester screen.
• Dirty air filter. Remove, clean and reinstall filter.
• Incorrect carburetor mixture adjustment setting. Have carburetor adjusted by an Authorized Service Center.

What do I do if the engine hesitates?

• Incorrect carburetor mixture adjustment setting. Have carburetor adjusted by an Authorized Service Center.

What do I do if there is no power under load?

• Incorrectly gapped spark plug. Clean / gap or replace plug.

What do I do if the engine runs erratically?

• Incorrectly gapped spark plug. Clean / gap or replace plug.

What do I do if the engine smokes excessively?

• Incorrect carburetor mixture adjustment setting. Have carburetor adjusted by an Authorized Service Center.

What do I do if the Ac circuit Breaker is “OFF”?

• Turn circuit breaker “ON”.

What do I do if there is no electricity?

• Defected electrical appliance or equipment Replace or repair defected electrical appliance or equipment.
• Fouled generator Have generator adjusted by an McCulloch Authorized Service Center.