NorthStar e300 User manual

1
M805020A.5
Engine Owner’s Manual:
Instructions for Set-up, Operation, Maintenance, Handling & Storage
WARNING
SPECIAL HAZARDS
•CO Poisoning: Exhaust from engine contains carbon monoxide, a poisonous gas that can cause carbon monoxide
poisoning and possible death if inhaled.
•Flying Debris: Engine can cause flying debris.
•Electric Shock: Operating engine in wet conditions or near water can cause electric shock.
•Fire/Explosion: Engine sparking can ignite fuel or other flammable liquids or vapors in the vicinity. Hot exhaust from engine
can ignite combustible materials.
•Burns: Engine have hot surfaces that can cause burn injuries.
Detailed safety information about these hazards appears throughout this manual.
Engine Protection Quick Facts
Inspect Upon Delivery: FIRST! Inspect for missing or damaged components. See “Initial Set-Up”section for where
to report missing or damaged parts.
***Add Engine Oil: Engine is shipped without oil. See Operations instructions for
information on capacity and viscosity recommendations.
Storage: See “Storage” section for more information.
Maintenance Schedule: Engine requires periodic inspection and servicing to keep functioning efficiently. See
“Maintenance Schedule Summary”in "Maintenance" section for frequency of servicing.
Any Questions, Comments, Problems, or Parts Orders
Call NorthStar Product Support 1-800-270-0810
ITEM NUMBER: 114593 (804313),
114594 (804314),
114656 (804315)
SERIAL NUMBER: ___________

Table of Contents
2
About Engine ........................................................................................................................3
Features ................................................................................................................................4
Specifications........................................................................................................................5
Component Identification .....................................................................................................7
Safety .....................................................................................................................................8
Safety Labeling......................................................................................................................9
Initial Set-Up ..........................................................................................................................11
Operation ...............................................................................................................................12
Step 1. Operation Instruction ..............................................................................................12
Step 2. Preparing For operation .........................................................................................13
Step 3. Add Fuel ................................................................................................................14
Step 3. Start/Stop Engine....................................................................................................15
Maintenance ..........................................................................................................................17
Storage...................................................................................................................................21
Troubleshooting....................................................................................................................22
Engine Parts Explosion ........................................................................................................24
Electrical Schematic Diagram ..............................................................................................42
Limited Warranty...................................................................................................................46

About Engine
3
Thank you for purchasing your NorthStar Engine!
It is designed for long life, dependability, and top
performance.
Intended Use. The engines in this manual can be
used in pressure washers, air compressor, water pump,
and other similar outdoor power equipment.
Note: Do not use for other unapproved purposes,
as unforeseen hazards or engine damage may
result.
Supplies Required. Normal operation will require you
to supply:
•Gasoline
•Engine oil
•Personal Protection Equipment
See “Specifications”section of this manual for more
detail.
Site Location. Intended for outdoor use only.
Personal Protection. Wear safety apparel during
operation, including safety glasses with side and top
protection. Ear protection is also recommended if
working near any operating engine. Other safety apparel
includes waterproof, insulated gloves and non-slip
protective footwear.
Adult Control only. Only trained adults should operate
this engine. Do not let children operate this engine.
Under The Influence. Never operate, or let anyone else
operate, this engine while fatigued or under the
influence of alcohol, drugs, or medication.
Keep this manual for reference and review.
ATTENTION: Rental Companies and Private
Owners who loan this engine/equipment to
others!
All persons to whom you rent/loan engine/equipment
powered by this engine, must have access to and read
this manual. Keep this owner’s manual with the
engine/product at all times and advise all persons who
will operate the engine to read it. You must also provide
personal instruction on how to safely set-up and
operate the engine and remain available to answer any
questions a renter/borrower might have. Owner’s
Manuals are available from NorthStar at 1-800-270-
0810.

Features
4
Electronic Fuel Injection (EFI) System
EFI replaces the need for carburetor that mixes air and fuel. It electronically injects fuel directly into an engine’s
intake manifold or cylinder.
The EFI system monitors parameters such as engine speed, intake pressure and temperatures when the engine
is started and warmed up. There are no adjustments to be made to EFI system. If there is a problem with startup
or operation, please immediately contact a NorthStar Authorized Service Center to solve the problem.
Advantages of EFI Engine:
1. More consistent power: An EFI engine is constantly self-adjusting and will run at its most
advantageous fuel and air mixture setting.
2. Better fuel efficiency: Electronic fuel injection improves engine's fuel efficiency (up to a 28%
improvement).
3. Fewer emissions: With increased fuel efficiency, exhaust emissions improvements will also occur.
4. Less Maintenance: Common maintenance issues with carbureted engines are eliminated, such as fuel
deposits and gumming of sensitive carburetor passageways.
5. Automatic altitude adjustments: EFI engine automatically adjusts fuel/air mixture to keep the engine
running when altitude changes.

Specifications
5
114593 (804313) –e300
114594 (804314) –e420
DIMENSIONS/COMPONENTS
DIMENSIONS/COMPONENTS
Engine Type
Four- stroke, Overhead, Single-
Cylinder
Engine Type
Four- stroke, Overhead, Single-
Cylinder
Length
18.90in
Length
20.28in
Width
13.00in
Width
14.57in
Height
17.91in
Height
18.31in
Net Weight
62.8lbs
Net Weight
76lbs
Displacement
301cc
Displacement
420 cc
Fuel Tank Capacity
1.45 Gal (5.5L)
Fuel Tank Capacity
1.64 Gal (6.2L)
Compression Ratio
8.2:1
Compression Ratio
8.2:1
Cylinder Diameter X
Stroke
3.15X2.36in
Cylinder diameter X
Stroke
3.54X2.60in
Maximum Output
Power
6.2 kW / 3600 rpm
Maximum Output
Power
8.8 kW / 3600 rpm
Net Torque
13.28ft-lbs. / 2500 rpm
Net Torque
18.44 ft-lbs. / 2500 rpm
Cooling System
Forced Air Cooling
Cooling System
Forced Air Cooling
Ignition System
Transistorized Coil Ignition (TCI)
Ignition System
Transistorized Coil Ignition (TCI)
Spark Plug
F6RTC / F7RTC
Spark Plug
F6RTC / F7RTC
Lubrication System
Splash Type
Lubrication System
Splash Type
Oil Capacity
1.06 qt. (33.81 oz.)
Oil Capacity
1.17 qt. (37.19 oz.)
Power Output Shaft
Direction
Counterclockwise
Power Output Shaft
Direction
Counterclockwise
Output Shaft
1in x 3.48in Length with 1/4in
keyway
Output Shaft
1in x 3.48in Length with 1/4in
keyway
Mounting Face
SAE J609 Flange B
5/16-24 UNF 2B Tap on a
5.00in(126.5mm) bolt circle
and 3/8-16 UNC 2B Tap on a
6.50in (165.1mm) bolt circle
Mounting Face
SAE J609 Flange B
5/16-24 UNF 2B Tap on a
5.00in(126.5mm) bolt circle
and 3/8-16 UNC 2B Tap on a
6.50in (165.1mm) bolt circle
Clearance of spark
plug
0.028 –0.031in
Clearance of spark
plug
0.028 –0.031in
Valve clearance
0.002 –0.0039in
Valve clearance
0.002 –0.0039in
Operating
Temperature (ºF)
14ºF to 104ºF
Operating
Temperature (ºF)
14ºF to 104ºF

Specifications
6
114656 (804315) –e420 (Electric Start)
DIMENSIONS/COMPONENTS
Engine Type
Four- stroke, Overhead, Single-
Cylinder
Length
19.5in
Width
14.57in
Height
18.31in
Net Weight
80.5lbs
Displacement
420 cc
Fuel Tank Capacity
1.64 Gal (6.2L)
Compression Ratio
8.2:1
Cylinder diameter X
Stroke
3.54X2.60in
Maximum Output
Power
8.8 kW / 3600 rpm
Net Torque
18.44 ft-lbs. / 2500 rpm
Battery Requirement
12 VDC –14 Ahr
*Battery required for operation
Cooling System
Forced Air Cooling
Ignition System
Transistorized Coil Ignition (TCI)
Spark Plug
F6RTC / F7RTC
Lubrication System
Splash Type
Oil Capacity
1.17 qt. (37.19 oz.)
Power Output Shaft
Direction
Counterclockwise
Output Shaft
1in x 3.48in Length with 1/4in
keyway
Mounting Face
SAE J609 Flange B
5/16-24 UNF 2B Tap on a
5.00in(126.5mm) bolt circle
and 3/8-16 UNC 2B Tap on a
6.50in (165.1mm) bolt circle
Clearance of spark
plug
0.028 –0.031in
Valve clearance
0.002 –0.0039in
Operating
Temperature (ºF)
14ºF to 104ºF

Component Identification
7
1. Fuel Tank Cap: Remove the fuel tank cap to add fuel once engine has cooled.
2. Fuel Tank: Storage for gasoline to power the engine.
3. Throttle Knob: Adjust the engine speed with the throttle knob.
4. Engine Start/Stop Button (Only Electric Start Model): Push button start/stop switch (Electric Start Model
Only)
5. Starter Recoil Handle: Pull the Starter Recoil handle to start the engine.
6. Spark Plug: Ignites compressed fuel and air within the combustion chamber of the engine.
7. Air Cleaner: Prevents dust and debris from entering the engine.
8. Muffler: The muffler reduces noise from engine. It will become hot during operation, do not touch.
9. Oil Drain Bolt: Remove oil drain bolt to drain oil from the engine. See “Maintenance”section of this manual.
10. Oil Dipstick: Remove oil dipstick and inspect to ensure proper oil level in engine.
11. Serial Number: Unique engine serial number etched into the engine block.
12. Engine Switch: Switch that turns the engine on and off.
13. Electric Starter Motor (Electric Start Model Only): Device which starts without pulling the recoil.
14. Battery Box (Recoil Start Models Only): Holds 2- 9V batteries to power ECU and fuel pump upon initial
starting.
15. NorthStar Illuminated Logo: Illuminates when Engine Switch is turned On
See “Parts Explosion” for more details
114656 (804315)
114593 (804313)
(FIG0804315_3)

Safety
8
Hazard Signal Word Definitions
DANGER
WARNING
CAUTION
CAUTION
NOTICE
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.
DANGER (red) indicates a hazardous situation, which if
not avoided, will result in death or serious injury.
WARNING (orange) indicates a hazardous situation,
which if not avoided, could result in death or serious
injury.
CAUTION (yellow) used with the safety alert symbol,
indicates a hazardous situation, which if not avoided,
could result in minor or moderate injury.
CAUTION (yellow) without the safety alert symbol, is
used to address practices not related to personal injury.
NOTICE is used to address practices not related to
personal injury.

Safety Labeling
9
Safety Decal Locations
WARNING
ALWAYS make sure safety labels are in place and in good condition. If a safety label is missing or not legible, order new labels
from NorthStar Product Support at 1-800-270-0810.
On-Product Warning Labels
Location
Part Numbers
Description
1
790852
Burn Hazard Decal
2
788935
Fuel Fire / Explosion Hazard
3
795124
Allowable Ethanol % In Fuel
4
805132
Poisonous Gas Decal
5
N/A
Emission Label
FIG804315_1

Safety Labeling
10
To order replacement safety labels, call NorthStar Product Support
at 1-800-270-0810.
4
3
2
1
5

Initial Set-Up
11
Outdoor Use Only
1. WARNING
Location Hazards
Choose a suitable site for operating your engine to
prevent possible death from carbon monoxide poisoning
or injury from fire/explosion, hot surfaces, or equipment
tip-over.
Select a suitable outdoor location:
1. Never run the engine in an enclosed or partially
enclosed location such as a building, garage,
barn, shed, or house. These spaces can trap
poisonous gases. Running a fan or opening
windows will not provide adequate ventilation to
prevent dangerous CO build-up.
2. Only use the engine outdoors at least 20 feet
from the home, away from windows, vents, and
air intakes, to allow proper ventilation. If you
start to feel sick, dizzy, or weak while using the
engine, shut off the engine and get to fresh air
RIGHT AWAY.
3. Position the engine so that the exhaust fumes
will not be directed towards people or building
air intakes.
4. Do not locate and use the engine in the
presence of flammable vapors, dust, gases, or
other potentially combustible materials.
5. Ensure that working, battery-operated or battery
back-up carbon monoxide alarms are used in
any dwelling/structure that is in close proximity
to the running engine.
Positioning:
1. Ensure the engine is positioned on a firm, level
(less than 3-degree slope), heat-resistant
surface.
2. Situate so there is adequate pulling room for
starting the engine using the recoil starter.
Attempting to pull at an odd angle could rip off
grip cord and/or cause muscular injuries to the
operator.
Airflow:
1. Situate so there is adequate clearance around
the engine to allow for airflow –at least 7 feet
from any non-combustible wall or obstruction.
2. Do not place any objects against or on top of
the engine.
3. The engine needs adequate, unobstructed flow
of air to allow for proper combustion and
adequate cooling. Proper combustion can only
be obtained when there is a sufficient supply of
oxygen available for the amount of fuel being
burned. Cooling ventilation is required to
prevent overheating of the engine and possible
fire.
Exhaust:
WARNING
Exhaust Modification Hazard
Never attempt to attach ductwork to the muffler system
to allow for installation inside an enclosure. This could
cause heat build-up and increased exhaust back-
pressure, resulting in possible exhaust leakage or
damage to the engine.
1. The exhaust gas from your engine is extremely
hot and can cause combustible materials to
catch on fire.
2. Make sure the engine is at least 7 feet from all
combustible materials and structures during
operation.
3. Keep a fire extinguisher rated "ABC" nearby.
Keep it properly charged and be familiar with its
use.
4. Place the engine so that the exhaust fumes will
not be directed towards people or building air
intakes.
DANGER
Carbon Monoxide Hazard
Exhaust fumes from the engine contain carbon
monoxide (CO), a poisonous gas you cannot see,
smell, or taste. The CO generated by the engine can
rapidly accumulate, even in areas that appear to be well
ventilated, resulting in dangerous and fatal
concentrations within minutes. NEVER run engine
inside any enclosed or semi-enclosed spaces, including
homes, garages, basements, sheds, boxes, pick-up
truck beds, RVs, or boats. These spaces can trap
poisonous gases, EVEN if you run a fan or open
windows. If you start to feel sick, dizzy, or weak while
using the engine, shut off the engine and get to fresh air
RIGHT AWAY. See a doctor. You may have carbon
monoxide poisoning.

Operation
12
Follow Safety Rules for Operation
After you have checked, oiled, and fueled the engine
and positioned it in a suitable worksite, it is time to
start your engine. The following are the procedures
necessary for safe, successful operation of your
engine.
WARNING
Failure to follow safety rules may result in serious injury
or death to the operator or bystanders.
Instruct Operators. Owner must instruct all operators in
safe set-up and operation. Do not allow anyone to
operate the engine who has not read the Owner’s
Manual and been instructed on safe use practices.
Safety Equipment/Controls. Always operate with all
safety covers, guards, and barriers in place and in good
working order, and all controls properly adjusted for safe
operation.
Moving Parts. Keep hands, feet, hair, and apparel
away from moving parts. Air vents may cover moving
parts and should be avoided as well.
Ear Protection. Hearing can be damaged from
prolonged, close-range exposure to the type of noise
produced by this engine. The use of ear plugs, or other
hearing protection devices is recommended for persons
working within 15-20 feet of the running engine for an
extended period of time.
Eye Protection. Wear ANSI “Z87.1” required safety
glasses when operating or servicing the engine.
NOTE!
Before starting the engine, review the following general
safety rules for operation:
Conditions for Use
Know How to Stop. Be thoroughly familiar with proper
use of the engine and all controls and connections.
Know how to stop the engine and depressurize the
system quickly if needed.
Instruct All Operators. The engine owner must instruct
all operators and potential renters in safe set-up and
operation. Do not allow anyone to operate the engine
who has not read the Owner's Manual and been
instructed on its safe use.
Adult Control only. Only trained adults should set up
and operate the engine. Do not let children operate.
Engine can generate forces greater than children can
control and require judgment beyond what can be
expected of children.
Under the Influence. Never operate, or let anyone else
operate, the engine while fatigued or under the influence
of alcohol, drugs, or medication.
Safety Equipment / Controls in place. Do not operate
the engine unless all safety covers, guards, and barriers
are in place and in good working order, and all controls
are properly adjusted for safe operation.
Damaged. Do not operate the engine with damaged,
missing, or broken parts. Never attempt to repair a
component. Always replace it with a part that is rated.
Modifications. Do not modify the engine in any way or
deactivate any safety device. Do not change or add to
fuel tank, fuel lines, or exhaust system. Modifications
can result in hazards related to carbon monoxide
poisoning, fuel leaks, fire, explosion, or other serious
safety hazards, and will also void the warranty.
During Use
Stay alert. Watch what you are doing at all times.
Clear work area. Clear the work area of all bystanders.
Keep children and pets away.
Keep engine away from electrical wiring. Engine
contact with electrical wiring will likely result in severe
electrical shock or electrocution.
Hot exhaust/parts. Stay clear of engine exhaust.
Never touch a hot engine muffler, or other hot surfaces.
All are very hot and will burn you. Cleaning should be
done with a damp sponge with the engine OFF.
Let engine cool at least two minutes before
refueling.

Operation
13
Preparing for Operation
Make sure that any regular maintenance has been
performed as prescribed in “Maintenance” section.
Check/Add Engine Oil
Use the recommended oil type for your engine and
expected ambient conditions.
WARNING
Burn Hazard
Never open oil port while engine is running. Hot oil can
spray over face and body.
Notes:
•Low oil shutdown feature prevents the engine from
starting without sufficient oil.
•Engine is shipped without oil. You must add oil
before first use.
Engine Oil. Use 4-stroke engine oil, API service
classification SN class or equivalent and above. Check
the API label on the oil container to be sure it includes the
letters SN class or equivalent and above.
SAE 10W-30 is recommended for general use. Other
viscosity shown in the chart may be used when the
average temperature in your area is within the indicate
range.
SAE Viscosity Grades
CAUTION
Oil is an important factor affecting the output and life of
the engine. Do not use unclean oil or two-stroke oil,
which may cause damage to the engine.
Oil level check:
1. Remove the oil dipstick and clean it with a rag.
2. Reinsert the dipstick into the oil filling hole
without screwing it in. Pull the dipstick out and
check the oil level. The dipstick has an “H” to
indicate proper oil level, and an “L” to indicate
oil level is too low.
3. If the oil level is too low, the engine will not start.
Add the recommended engine oil, to the “H”
mark on the oil dipstick.
4. Reinstall the dipstick.
5. Oil Capacity:
1) 114593 (804313) = 1.06 qt. (33.8oz.)
2) 114594 (804314) = 1.17 qt. (37.2oz)
3) 114656 (804315) = 1.17 qt. (37.2oz)
CAUTION
Running the engine with insufficient engine oil may
damage the engine severely and would not be covered
under warranty.
Air Cleaner
Remove the air cleaner cover and check the filter to
make sure it is clean and not damaged. Clean or
replace as necessary. See “Maintenance”section of this
manual for details.
CAUTION
Never run the engine without the air filter and cover
installed or damage to the engine could result. Damage
to the engine by not having the air filter and cover
installed is not covered under warranty.

Operation
14
Add Fuel
WARNING
Fuel Fire/Explosion Hazard
Gasoline is highly flammable and explosive. Heat,
sparks, and flames can ignite fuel vapors, which can
become widespread during fueling. A flash fire
and/or explosion could result and cause serious
injury or death. Always use extreme care when
handling fuels. Carefully follow all instructions to
avoid the following conditions which could result in
fuel ignition:
•gas vapor collection inside enclosures
•static electric sparks
•sparks from electric wiring, batteries, or running
engines
•sources of heat (such as a hot engine exhaust)
•open flames, including pilot lights
Always follow these general safety rules when
fueling:
1) Turn engine off and allow to cool for at least two
minutes before removing any fuel tank cap.
Note: A running, or still-hot engine is hot enough to
ignite fuel.
2) Fill fuel tank OUTDOORS –never indoors. Fuel
vapors can ignite if they collect inside, and
enclosure and explosion can result.
3) Stay away from all sources of heat, sparks, and
flames. Do not smoke.
4) Never pump fuel directly into the gas tank at a gas
station –it could cause a static electric spark.
Follow these steps to avoid static electric sparking
during fueling:
•Always place container on the ground to be
filled. Never fill the portable gas container while
it is sitting inside a vehicle, trailer, trunk, or pick-
up truck bed.
•Dissipate static charge from your body before
beginning the fueling process by touching a
grounded metal object at a safe distance from
fuel sources.
•Keep nozzle in contact with container while
filling. Do not use a nozzle lock-open device.
5) Clean up fuel spills/splashes immediately.
•Wipe up spilled fuel and wait 5 minutes for
excess fuel to evaporate before starting engine.
•Fuel-soaked rags are flammable and should be
disposed of properly.
•If fuel is spilled on your skin or clothes, change
clothes and wash skin immediately.
Fill Engine Fuel Tank
Check the gasoline tank level. If needed, fill tank
with fresh unleaded gasoline from a portable container:
1) Remove engine fuel tank cap.
2) Add gasoline through the fill opening:
- Use only a UL-approved portable gasoline
container to transfer the gasoline to engine's tank.
- Do NOT overfill the gasoline tank. Never fill fuel
above the maximum fuel level and into the filter
filler shoulder area.
3) Replace fuel tank cap securely before starting
engine.
4) Store extra gasoline in a cool, dry place in a UL-
approved container.
Fuel Filler
Filter Filler
Shoulder
Maximum Fuel
Level
Fill Opening

Operation
15
Inspect Fuel System/Check for Leaks
Inspect the engine fuel system and check for leaks
before each use.
Do not start engine until all needed repairs have been
completed.
WARNING
Fuel Leak Hazard
Gasoline fuel is highly explosive and fuel leaks
can result in fire or explosions. You can be
burned and seriously injured if the fuel system is
not properly hooked up or there is a fuel leak
when you start the engine.
Inspect the entire fuel system. Look for:
•signs of leaks or deterioration
•chafed or spongy fuel hose
Perform Scheduled Maintenance, As needed
•Make sure that any other regular maintenance
has been performed as prescribed in this manual
in the "Maintenance Schedule Summary" section.
•Refer to the engine Owner's manual for engine
maintenance instructions.
Starting the Engine (Recoil Models Only):
114593 (804313) and 114594 (804314):
1.Adjust the throttle speed to maximum speed.
2.Toggle the engine switch to the "ON" position.
(NorthStar illuminated logo will illuminate fuel pump
will power on).
3.Pull the recoil to start the engine.
CAUTION
Do not release the starter handle suddenly after starting
to avoid it from recoiling back and hitting the engine. It
should be released slowly with the rebound of the
starter rope.
•For electronic fuel injection (EFI) engines,
no altitude adjustment is required.
Starting the Engine (Electric Start)
114656 (804315:)
Note: A 12V 14Ah (minimum) battery is required for
operation of this engine.
Connect the positive wire (+) to the positive pole (+)
of the battery. Connect the negative wire (-) to the
negative pole (-) of the battery.
1) Toggle the engine switch to the “ON” position.
(Engine Start/Stop button will have solid red
illumination). This will allow the engine to start.
Alternatively, pull the recoil to start the engine.

Operation
16
2) Press the Engine Start/Stop button to start the
engine (Engine Start/Stop button will blink green
illumination while engine start and turn solid
green once engine has successfully started).
NOTICE:
•The engine will repeat the start
sequence three times if the engine
fails to start. To terminate startup,
toggle the engine switch to the
"OFF" position.
•When not in use, keep the engine
switch at the "OFF" position to
avoid the loss of battery power.
Shutdown of the Engine (Recoil Models
Only):
114593 (804313) and 114594 (804314):
1. Toggle the engine switch to
the "OFF" position.
Shutdown of the Engine (Electric Start
Model Only):
114656 (804315):
1. Press and release the
Engine Start/Stop button
(Engine Start/Stop will blink
red while engine is stopping
and turn solid red once
engine has successfully
shutdown).
2. Toggle the engine switch
to "OFF" position.
NOTE:
•In case of emergency, the engine
switch can be directly toggled
to the "OFF" position.
•When not in use, keep the engine
switch at the "OFF" position to
avoid the loss of battery power.

Maintenance
17
WARNING
Maintenance Hazards
ALWAYS turn off engine, and disconnect the spark plug wire before cleaning, adjusting, or servicing the engine. After
servicing, make sure all guards and cover shields are replaced before using.
Maintenance Schedule Summary
Maintenance period
Item
Each
use
First month or
20 hours
Every 3 months or
50 hours
Every 6 months
or 200 hours
Every year or
300 hours
Engine oil
Check level
√
Change
√
√
Air filter element
Inspection
√
Clean
√
Replace
√*
Spark plug
Replace
√**
Spark arrester
Clean
√*
Replace batteries (Recoil
engines only)
√**
Idle
Check-adjust
√
Valve clearance
Check-adjust
√***
Fuel tank and fuel filter
Clean
√
Fuel hose
Inspection
Every 2 years (replace it if necessary)
* Service more frequently when used in dusty environments.
** If necessary.
*** These items shall be maintained by a NorthStar Authorized Service Center unless the user has proper tools
and maintenance capability.

Maintenance
18
No modifications. Never modify or alter the engine in
any way. Modifications can create serious safety
hazards and will also void the warranty.
Improper maintenance or failure to perform pre-
operation checks before operation will result in
malfunctions that could cause serious injury to you or
others.
Follow Safety Rules
Read and follow these safety rules whenever you
will be servicing the engine:
•Turn off. Always turn off before inspection or
maintenance. Remove spark plug or spark plug wire
to prevent accidental starting.
•Replace guards. Make sure all guards and cover
shields are replaced after servicing.
•Major repair. Major service, including the installation
or replacement of parts, should be performed only by a
qualified service technician. Obtain factory approved
parts from NorthStar Product Support at 1-800-270-
0810.
•Replacement parts. If a part needs replacement, only
use factory approved repair parts. Replacement parts
that do not meet specifications may result in a safety
hazard or poor operation of the engine and will void the
warranty.
Keep Engine Clean
If dust or debris accumulates on the engine, clean with a
damp cloth or soft bristle brush. Do not allow air intakes
to become blocked.
DANGER
Carbon Monoxide Hazard
Exhaust fumes from the engine contain carbon monoxide
(CO), a poisonous gas you cannot see, smell, or taste. The CO
generated by the engine can rapidly accumulate, even in areas
that appear to be well ventilated, resulting in dangerous and fatal
concentrations within minutes. NEVER run engine inside any
enclosed or semi-enclosed spaces, including homes, garages,
basements, sheds, boxes, pick-up truck beds, RVs, or boats.
These spaces can trap poisonous gases, EVEN if you run a fan
or open windows. If you start to feel sick, dizzy, or weak while
using the engine, shut off the engine and get to fresh air RIGHT
AWAY. See a doctor. You may have carbon monoxide poisoning.
Improper maintenance or failure to perform pre-
operation checks before operation will result in
malfunctions that could cause serious injury to you or
others.
Changing Engine Oil
WARNING
Burn Hazard
Never open oil port while engine is running. Hot oil can
spray over face and body.
1) Drain the oil when the engine is warm to ensure
quick and thorough draining
2) Unscrew the oil dipstick and oil drain bolt to drain the
oil. Replace the oil drain bolt and tighten it.
3) Refill the recommended oil and check the oil level.
4) Reinstall the oil dipstick.
NOTICE:
Dispose of used motor and pump oil in a manner that is
compatible with the environment and in accordance
with local, state, and federal laws and regulations.
•Take used oil in a sealed container to your local
recycling center or service station for reclamation.
•Do not throw it in the trash, pour it on the ground, or
pour it down the drain.
Oil dipstick
Oil drain bolt
Gasket

Maintenance
19
Air Filter Maintenance
A dirty air filter may restrict air from entering the engine.
To prevent engine failure, the air filter should be
maintained regularly. If the engine is operated in a dusty
place, it needs to be maintained more frequently.
WARNING
Never use fuel or a solvent with a low ignition point
to clean the air filter element, doing so may cause
explosion. Please clean the element with warm
soapy water or non-flammable solvents.
CAUTION
Never run the engine without the air filter and cover
installed or damage to the engine could result. Damage
to the engine by not having the air filter and cover
installed is not covered under warranty.
1) Remove the air filter cover and air filter element
assembly.
2) Carefully separate the foam filter element from the
Paper filter element assembly.
a. Paper filter element: Remove the dust by
tapping the filter element several times on a
hard surface or use compressed air from inside
out.
b. Foam filter element: Wash it with warm, soapy
water, then dry it. Soak it in the clean engine oil
and squeeze out the excess oil. If too much oil
remains in the foam filter element, there will be
smoke coming out from the engine in the initial
startup stage.
3) Clean off dust on the air filter cover and inner
surface with a wet rag. Be careful not to allow
dust to enter the engine.
4) Install the filter element assembly and the air
filter cover.
Air filter holder
assembly
Sealing ring
Air filter base
Air filter element
assembly
Knob
Air filter cover
Butterfly nut

Maintenance
20
Spark Plug Maintenance
To ensure proper operation of the engine, the spark plug
must be provided with proper clearance and are free of
deposits.
1) Remove the spark plug wire.
2) Clean the dirt around the spark plug holder.
3) Remove the spark plug with a spark plug socket
wrench.
4) Visually inspect the spark plug. If it is damaged,
replace it with a new one. If the spark plug can still
be used, clean it with a wire brush.
5) Measure the spark plug gap.
6) To prevent misalignment of the threads, screw the
spark plug into the screw hole by hand.
7) After the spark plug is screwed to the end, tighten it
with spark plug socket wrench.
a) To install a new spark plug, the user
should replace it according to the original
spark plug type. Thread the spark plug
into the engine until hand tight, then an
additionally 1/2 turn (after hand tight).
b) If a used spark plug is reinstalled, thread
the spark plug into the engine until hand
tight, then an additionally 1/8-1/4 turn
(after hand tight).
CAUTION
The spark plug must be tightened properly, or it may be
extremely hot and damage the engine.
Battery Replacement (Recoil Only Engines -
114593 (804313) and 114594 (804314)
To ensure efficient starting of the engine, the batteries will
need to be replaced periodically.
1) Remove Battery Cover Screws and Battery Cover.
2) Remove and replace batteries. Use two fresh 9V
(6LR61) batteries. Do not mix old/new …
3) Replace Battery Cover and Battery Cover Screws
High Altitude Operation
One of the benefits of an EFI engines, is that it can
adjust fuel and air based on various ambient conditions.
For high altitude operation, no engine modification is
required.
For additional question go to www.northerntool.com or
contact us at 1-800-270-0810.
Spark plug socket wrench
Spark plug wire
0.028-0.031in
(2) 9V Batteries
(6LR61)
Battery Cover
Battery Cover Screw