WEN POWER 56173 User manual

173cc Vertical
Engine
Item # 56173
Owner’s Manual
Manual del Propietario
Questions? Problems?
Please call our customer help line:
[phone] M-F 8-5 CST
FEATURES
•Low Oil Automatic Shutoff
•Circuit Breaker for Overload Protection
•0.3 Gallon Fuel Tank Capacity
•Meets EPA Phase III Emission Standards and CARB Emission Standards
2012
www.wenproducts.com

ENGINE IDENTIFICATION
For information and questions, please contact the Customer Service Help Line by calling 800-232-
1195. Certain information will be requested by the Customer Service Representative and to facilitate
that, please fill in the information below.
Refer to the illustration below for the location of Serial Number. Record engine information in the
spaces provided below.
DATE OF PURCHASE: ______________________________________________
PURCHASED FROM: ______________________________________________
ITEM NUMBER: ____________________________________________________
ENGINE SERIAL NUMBER: _________________________________________
Serial Number
SERVICE RECORD
Record Service Dates:
Date Date Date Date Date Date
Oil Change
Change spark plug
Clean Fuel Tank
Clean Air Cleaner
i

TABLE OF CONTENTS
ENGINE IDENTIFICATION..........................................................................................................i
SERVICE RECORD.........................................................................................................................i
INTRODUCTION............................................................................................................................1
SAFETY INFORMATION..............................................................................................................2
GENERAL SAFETY PROCEDURES...........................................................................................3
IMPORTANT SAFETY INSTRUCTIONS...................................................................................4
ENGINE COMPONENTS...............................................................................................................4
SET UP..............................................................................................................................................6
ENGINE PREPARATION..............................................................................................................7
Using the Engine for the First Time ...............................................................................................7
Step 1 - Fill Oil ...........................................................................................................................7
Step 2- Add Gasoline..................................................................................................................8
STARTING THE ENGINE.............................................................................................................9
SUBSEQUENT STARTING OF THE ENGINE.........................................................................10
Step 1- Check the Oil................................................................................................................10
Step 2 – Check the Fuel Level..................................................................................................11
STOPPING THE ENGINE ...........................................................................................................11
MAINTENANCE / CARE.............................................................................................................12
Cleaning the Engine......................................................................................................................12
Checking the Oil...........................................................................................................................12
Changing/ Adding Oil ..................................................................................................................13
Air Cleaner Maintenance..............................................................................................................13
Spark Plug Maintenance...............................................................................................................13
Draining the Fuel Tank.................................................................................................................14
STORAGE / TRANSPORT PROCEDURES ..............................................................................15
SPECIFICATIONS........................................................................................................................16
TROUBLESHOOTING.................................................................................................................18
EXPLODED VIEW AND PARTS LIST......................................................................................21
WARRANTY STATEMENT........................................................................................................25
ii

INTRODUCTION
Thank You for Purchasing a WEN Power TM Product.
.
This manual provides information regarding the safe operation and maintenance of this product.
Every effort has been made to ensure the accuracy of the information in this manual.
WEN Power TM reserves the right to change this product and specifications at any time without
prior notice.
Please keep this manual available to all users during the entire life of the product.
Special Messages
This manual contains special messages to bring attention to potential safety concerns, engine
damage as well as helpful operating and servicing information. Please read all the information
carefully to avoid injury and machine damage.
Questions? Problems?
In order to answer questions and solve problems in the most efficient and speedy manner,
contact Customer Service at: [phone] M-F 8-5 CST
NOTICE REGARDING EMISSIONS
Engines that are certified to comply with U.S. EPA emission regulations for SORE (Small Off
Road Equipment), are certified to operate on regular unleaded gasoline, and may include the
following emission control systems: (EM) Engine Modifications and (TWC) Three-Way Catalyst
(if so equipped).
1

SAFETY INFORMATION
Before operating this engine read and observe all warnings, cautions, and instructions on this
sheet, on the engine, and in the Owner’s Manual.
NOTE: The following safety information is not meant to cover all possible conditions and
situations that may occur. Read the entire Owner’s Manual for safety and operating
instructions. Failure to follow instructions and safety information could result in serious
injury or death.
This safety alert symbol is used to identify safety information about hazards that can result in
personal injury.
A signal word (DANGER, WARNING, or CAUTION) is used with
the alert symbol to indicate the likelihood and the potential severity of injury. In
addition, a hazard symbol may be used to represent the type of hazard.
DANGERindicates a hazard, which, if not avoided, will result in death or serious
injury.
WARNING indicates a hazard, which, if not avoided, could result in death or
serious injury.
CAUTION indicates a hazard, which, if not avoided, might result in minor or
moderate injury.
CAUTION, when used without the alert symbol, indicates a situation that could
result in damage to the engine or engine.
SAFETY SYMBOLS AND MEANINGS
2

GENERAL SAFETY PROCEDURES
For any questions regarding the hazard and safety notices listed in this manual or on the
product, please call [phone] M-F 8-5 CST before using the engine.
DANGER: CARBON MONOXIDE. Using an engine indoors CAN KILL
YOU IN MINUTES.
Engine exhaust contains carbon monoxide (CO). This is a poison gas you cannot
see or smell. If you can smell the engine exhaust, you are breathing CO. But even
if you cannot smell the exhaust, you could be breathing CO.
•NEVER use an engine inside homes, garages, crawlspaces, or other partly enclosed
areas. Deadly levels of carbon monoxide can build up in these areas. Using a fan or
opening windows and doors does NOT supply enough fresh air.
•ONLY use an engine outside and far away from windows, doors, and vents. These
openings can pull in engine exhaust.
Even if you use an engine correctly, CO may leak into the home. ALWAYS use a battery-
powered or battery-backup CO alarm in the home.
If you start to feel sick, dizzy, or weak after the engine has been running, move to fresh air
RIGHT AWAY. See a doctor. You may have carbon monoxide poisoning.
WARNING: The exhaust from this product contains chemicals known to the
State of California to cause cancer, birth defects, or other reproductive harm.
WARNING: This engine may emit highly
flammable and explosive gasoline vapors, which can
cause severe burns or even death, if ignited. A nearby open flame can lead to
explosion even if not directly in contact with gasoline.
•Do not operate near open flame.
•Do not smoke near engine.
•Always operate on a firm, level surface.
•Always turn engine off before refueling. Allow engine to cool for at least 2 minutes
before removing fuel cap. Loosen cap slowly to relieve pressure in tank.
•Do not overfill fuel tank. Gasoline may expand during operation. Do not fill to the
top of the tank. Allow for expansion.
•Always check for spilled fuel before operating.
•Empty fuel tank before storing or transporting the engine.
•Before transporting, turn fuel valve to off and disconnect spark plug wire.
3

WARNING: This engine produces heat when running. Temperatures near
exhaust can exceed 150º F (65º C).
•Do not touch hot surfaces. Pay attention to warning labels on the engine identifying hot
parts of the machine.
•Allow engine to cool down after use before touching engine or areas of the engine that
become hot during use.
CAUTION: Misuse of this engine can damage it or shorten its life.
•Use engine only for its intended purposes.
•Operate only on dry, level surfaces.
•Turn engine switch to “off” position when the engine is not running.
IMPORTANT SAFETY INSTRUCTIONS
•SAVE THESE INSTRUCTIONS – This manual contains important instructions for WEN
engine that should be followed during installation and maintenance of the engine.
•Engines vibrate in normal use. Have damaged items repaired or replaced as necessary.
In addition to the previous safety notices, please become familiar with the safety and hazard
markings on the engine.
4

ENGINE COMPONENTS
Please familiarize yourself with the locations and functions of the various components and controls
of your engine.
Dipstick
Starter Handle
Fuel Cap
Muffler
Air Cleaner
5

SET UP
Warning:
TO PREVENT SERIOUS INJURY:
Operate only with proper spark arrestor installed.
Operation of this equipment may create sparks that can start fires around dry vegetation. A spark
arrestor may be required. The operator should contact local fire agencies for laws or regulations
relating to fire prevention requirements.
The operator should contact local fire agencies for laws or regulations relating to fire
prevention requirements.
At high altitudes, the engine’s carburetor, governor (if so equipped), and any other parts that
control the fuel-air ratio will need to be adjusted by a qualified mechanic to allow efficient high
altitude use and to prevent damage to the engine and any other devices used with this product.
1. IMPORTANT: If you have any doubts about your
ability to perform the following procedures, have a
qualified service technician perform the installation.
2. Install this engine on a lawn mower only.
3. Set the Engine upright on the mower, and align at least
three 3/8” diameter coarse threaded engine mounting
holes with mower mounting holes.
NOTE: Depending on the mower, it may be necessary to
drill mounting holes or make a mounting plate to align
with the engine mounting holes. Only a qualified
technician should attempt these solutions.
4. Use 3/8” diameter, coarse threaded, hardened,
stainless steel Bolts, Lock Washers, and
Washers (not included) of appropriate length
to secure the Engine to the mower.
Make sure the hardware does not contact
moving parts.
5. Insert the mower’s brake cable sheath through
the hole in the Brake bracket. Secure the
mower brake cable to the brake arm. Adjust
the brake cable sheath to remove all slack and
secure it in place using the adjusting nuts on
the cable sheath, as shown in the illustration
below.
THE ENGINE BRAKE IS FOR EMERGENCY SHUTOFF; DO NOT REPLACE THE BRAKE
SPRING WITH A WEAKER SPRING. If operating the engine brake is too difficult, a qualified
technician must install a different brake handle on the mower.
Note: The brake cable on some mowers may need to be adjusted in a different manner. Install
according to mower manufacturer’s instructions.
6. Attach the end of the mower’s Choke Cable to the Choke. Use the Bracket and Bolt to secure
its sheath in place as shown above.
7. This engine is set to a single speed that should not be adjusted.
8. Refer to the mower’s service manual for instructions on how to properly attach a belt drive
pulley, chain drive gear, etc. onto the output shaft of the engine.
6

ENGINE PREPARATION
Using the Engine for the First Time
The following section describes steps necessary to prepare the engine for use. If after
reading this section, you are unsure about how to perform any of the steps please call (800)
232-1195 M-F 8-5 CST for customer service. Failure to perform these steps properly can
damage the engine or shorten its life.
Step 1 - Fill Oil
The engine is shipped without oil. User must add the proper amount of oil before operating the
engine for the first time. The oil capacity of the engine crankcase is 0.5 quart.
Select good quality detergent oil bearing the American Petroleum Institute (API) service
classifications SJ, SL, or SM. (Synthetic oils may be used.) Use the SAE viscosity grade
of oil from the following chart that matches the starting temperature anticipated before
the next oil changes.
Figure1- Engine oil recommendations
To fill oil to the crankcase, follow these steps:
1. Make sure the engine is on a level surface. Tilting the engine to assist in filling will cause
oil to flow into engine areas and will cause damage. Keep engine level!
2. Remove the oil filler/dipstick cap from the engine.
3. Using a funnel, add the appropriate type and amount of oil into the crankcase. The
crankcase is full when the oil level has reached the second thread from the lip of the
opening.
4. Check for oil leaks. Reinstall oil filler cap before starting engine.
7

Step 2- Add Gasoline
WARNING: This engine may emit highly
flammable and explosive gasoline vapors, which can
cause severe burns or even death if ignited. A nearby
open flame can lead to explosion even if not directly in contact with gasoline.
•Do not operate near open flame.
•Do not smoke near engine.
•Always operate on a firm, level surface.
•Always turn engine off before refueling. Allow engine to cool for at least 2 minutes
before removing fuel cap. Loosen cap slowly to relieve pressure in tank.
•Do not overfill fuel tank. Gasoline may expand during operation. Do not fill to the
top of the tank. Allow for expansion.
•Always check for spilled fuel before operating. Clean up any spilled fuel before
starting.
•Empty fuel tank before storing or transporting the engine.
•Before transporting, turn fuel valve to off position and disconnect spark plug wire.
Use fresh (within 30 days from purchase), unleaded gasoline with a minimum 87 octane rating. Do
not use gasoline which contains Methanol. Do not mix oil with gasoline.
To add gasoline, follow these steps:
1. Make sure the engine is on a level surface.
2. Unscrew fuel cap and set aside (NOTE: the fuel cap may be tight and hard to unscrew).
3. Slowly add unleaded gasoline to the fuel tank. Be careful not to overfill. The fuel tank
capacity is 0.9 gallon. NOTE: Do not fill the fuel tank to the very top. Gasoline will
expand and spill over during use even with the fuel cap in place.
4. Reinstall fuel cap and wipe off any spilled gasoline with a dry cloth.
IMPORTANT:
•Never use an oil/gasoline mixture.
•Never use old gasoline.
•Avoid letting dirt or water into the fuel tank.
•Gasoline can age in the tank and make it hard to start up the engine in the future. Never
store engine for extended periods of time with fuel in the tank.
8

STARTING THE ENGINE
Before starting the engine, make sure you have read and performed the steps in the
“Engine Preparation” section of this manual. If you are unsure about how to perform any of
the steps in this manual please call [phone] M-F 8-5 CST for customer service.
DANGER: CARBON MONOXIDE. Using an engine indoors CAN KILL YOU
IN MINUTES.
Engine exhaust contains carbon monoxide (CO). This is a poison gas you cannot
see or smell. If you can smell the engine exhaust, you are breathing CO. But even
if you cannot smell the exhaust, you could be breathing CO.
•NEVER use an engine inside homes, garages, crawlspaces, or other partly enclosed
areas. Deadly levels of carbon monoxide can build up in these areas. Using a fan or
opening windows and doors does NOT supply enough fresh air.
•ONLY use an engine outside and far away from windows, doors, and vents. These
openings can pull in engine exhaust.
Even if you use an engine correctly, CO may leak into the home. ALWAYS use a battery-
powered or battery-backup CO alarm in the home.
If you start to feel sick, dizzy, or weak after the engine has been running, move to fresh air
RIGHT AWAY. See a doctor. You may have carbon
monoxide poisoning.
To start your engine, perform the following steps:
1. Press the Priming Bulb 2-3 times to prime the engine.
2. If the engine is cold, adjust the Mower’s choke control to
the CHOKE (START/CLOSED) position.
Note: Location, operation, and design of the choke control
will vary from manufacturer to manufacturer. Adjust the
control so that it pulls the choke cable to close the choke.
3. Hold the mower’s brake handle closed.
9

4. Grip the Starter Handle of the Engine loosely and pull it
gently until resistance is felt. Allow Cable to retract fully
and then pull it quickly. Repeat until the engine starts.
Note: Do not let the Starter Handle snap back against the
engine. Hold it as it recoils so it doesn't hit the engine.
5. Allow the Engine to run for several seconds. Then, if the
Mower’s choke control is in the CHOKE
(START/CLOSED) position, move the choke control
very slowly to its RUN (OPEN) position.
NOTE: Moving the Choke Lever too fast could stall the
engine.
IMPORTANT: Allow the engine to run at no load for a
minute or two with no load after each start-up so that the
engine can stabilize.
6. Break-in Period:
a. Breaking-in the engine will help to ensure proper equipment and engine operation.
b. The operational break-in period will last about 3 hours of use. During this period:
Do not apply a heavy load to the equipment.
c. The maintenance break-in period will last about 20 hours of use. After this period:
Change the engine oil.
Under normal operating conditions subsequent maintenance follows the schedule explained
in the MAINTENANCE AND SERVICING section.
SUBSEQUENT STARTING OF THE ENGINE
If this is not the first time using the engine, user should take the following steps to prepare it for
operation.
IMPORTANT: At this point the user should be familiar with the procedures described in the
section titled “Using the Engine for the First Time.” If the user has not yet read this section,
go back and read it now.
Step 1- Check the Oil
Oil consumption is normal during engine usage. The engine is equipped with a low-oil shutoff to
protect it from damage. The oil level in the engine should be checked before each use to ensure
that the engine crankcase contains sufficient lubricant.
To check or add oil, follow these steps:
1. Make sure the engine is on a level surface. Clean around oil fill.
2. Remove the oil filler/dipstick cap and check oil level.
3. If oil level is below the second thread from the lip of the oil fill opening, slowly add oil
until the engine crankcase is filled.
4. Reinstall and tighten oil filler cap before starting the engine. .
10

Step 2 – Check the Fuel Level
Before starting the engine, check to see that there is sufficient gasoline in the fuel tank. The fuel
gauge on top of the engine will indicate the fuel level in the tank. Add gasoline if necessary but
leave sufficient room in tank for expansion.
WARNING: This engine may emit highly
flammable and explosive gasoline vapors, which can
cause severe burns or even death if ignited. A nearby
open flame can lead to explosion even if not directly in contact with fuel.
•Do not operate near open flame.
•Do not smoke near engine.
•Always operate on a firm, level surface.
•Always turn engine off before refueling. Allow engine to cool for at least 2 minutes
before removing fuel cap. Loosen cap slowly to relieve pressure in tank.
•Do not overfill fuel tank. Gasoline may expand during operation. Do not fill to the
top of the tank. Allow for expansion.
•Always check for spilled fuel before operating. Clean up any spilled fuel before
starting.
•Empty fuel tank before storing or transporting the engine.
•Before transporting, turn fuel valve to off and disconnect spark plug wire.
IMPORTANT:
•Use only UNLEADED gasoline with an octane rating of 87 or higher.
•Do not use old gasoline.
•Never use an oil/gasoline mixture.
•Avoid letting dirt or water into the fuel tank.
STOPPING THE ENGINE
To stop the engine:
To stop the engine, release the brake handle.
WARNING:Allow the engine to cool for
several minutes before touching areas that
become hot during use.
CAUTION: Allowing gasoline to sit in the engine tank for
long periods of time without use can make it difficult to start the engine in the future. Never
store engine for extended periods of time with fuel in the tank.
11

MAINTENANCE / CARE
Proper routine maintenance of your engine will help prolong the life of your machine. Please
perform maintenance checks and operations according the schedule below.
If you have questions about any of the maintenance procedures listed in this manual, please
call [phone] M-F 8-5 CST.
CAUTION: Never perform maintenance operations while the engine is running.
Recommended Maintenance Schedule
each use
first month
then ever
y
20 hrs
every 3
months or
50 hrs
every 6
months or
100 hrs ever
y
y
ear
or 300 hrs
Engine oil
check level x replace x x
Air cleaner
check x clean x
fuel filter
cup clean x
spark plug check/ clean x
fuel tank
check fuel level x clean x
Recommended maintenance schedule
Cleaning the Engine
Never clean the engine when it is running! Never clean with a bucket of water or a hose. Water
can get inside the working parts of the engine and cause a short circuit or corrosion.
Always try to use the engine in a cool, dry place. If the engine becomes dirty, clean the exterior
with a damp cloth, a soft brush, vacuum or pressurized air.
Checking the Oil
Check the oil level of the engine according to the Recommended Maintenance Schedule in Figure
7. The engine is equipped with an automatic shutoff to protect it from running with low oil
pressure. The engine should be checked before each use for proper oil level. This is a critical step
for proper engine starting.
To check or add oil, follow these steps:
1. Make sure the engine is on a level surface. Clean around oil fill.
2. Remove the oil filler/dipstick cap and check oil level.
12

3. If oil level is below the second thread from the lip of the oil fill opening, slowly add oil
until the engine crankcase is filled.
4. Reinstall and tighten oil filler cap before starting the engine.
Changing/ Adding Oil
Change the oil according to the maintenance schedule. Change the oil when the engine is warm.
This will allow for complete drainage. Change oil more often if operating under heavy load or
high ambient temperatures. It is also necessary to drain the oil from the crankcase if it has become
contaminated with water or dirt.
The oil capacity of the engine in this engine is 0.5 quart. Add oil when the oil level is low.
To fill the crankcase with oil, follow these steps:
1. Make sure the engine is on a level surface. Tilting the engine to assist in filling will cause
oil to flow into engine areas and will cause damage. Keep engine level!
2. Remove the oil filler/dipstick cap from the engine.
3. Using a funnel, add the appropriate type and amount of oil into the crankcase. The
crankcase is full when the oil level has reached the second thread from the lip of the
opening.
4. Check for oil leaks. Reinstall oil filler cap before starting engine.
NOTE: Never dispose of used motor oil in the trash or down a drain. Please call your local
recycling center or auto garage to arrange oil disposal.
Air Cleaner Maintenance
Routine maintenance of the air cleaner helps maintain proper air flow to the carburetor. Check that
the air cleaner is free of excessive dirt.
1. Remove the air cleaner cover and the air cleaner elements and check for dirt. Clean or replace
if necessary.
2. Wipe the dirt from inside the empty air cleaner casing.
Spark Plug Maintenance
The spark plug is important for proper engine operation. A good spark plug should be intact, free
of deposits, and properly gapped. To inspect the spark plug:
1. Pull on the spark plug cap to remove it.
2. Unscrew the spark plug from the engine using the spark plug wrench included with this
product.
3. Visually inspect the spark plug. If it is cracked or chipped, discard and replace with a new
spark plug.
4. Measure the plug gap with a gauge . The gap should be 0.7-0.8mm (0.028-0.031in).
5. If you are re-using the spark plug, use a wire brush to clean any dirt from around the spark
plug base and then re-gap the spark plug.
6. Screw the spark plug back into its place on the engine using the spark plug wrench. Do not
over-tighten spark plug. Recommended tightening of spark plug is ½ to ¾ of a turn after
spark plug gasket contacts spark plug hole. Reinstall the spark plug cap.
13

0.7-0.8 mm
(0.028-0.031 in)
Measuring the spark plug gap
Recommended Spark Plug: NGK- BP7ES, Torch- F6TC
Draining the Fuel Tank
Clean fuel tank each year or before storing the engine for extended periods of time. To drain the
fuel tank and carburetor:
1. Turn the fuel valve to the “OFF” position. Move the engine in a well-ventilated area away
from ignition sources.
2. Place a funnel leading to a proper gasoline container below the carburetor.
3. Remove the drain bolt from the bottom of the carburetor bowl and allow the fuel to drain.
4. Open the fuel valve. After all fuel has drained, reinstall the drain bolt. Tighten securely.
5. Store the emptied gasoline in a suitable place.
CAUTION: Do not store fuel for more than 3 months.
14

STORAGE / TRANSPORT PROCEDURES
CAUTION: Never place any type of storage cover on the engine
while it is still hot.
If the engine is being stored for short periods of time (30 – 60 days), add stabilized fuel to the fuel
tank until full. NOTE: Filling the tank reduces the amount of air in the tank and helps reduce
deterioration of fuel. Run the engine for 2 – 3 minutes allowing stabilized fuel mixture to
circulate through the carburetor.
When transporting or storing the engine for extended periods of time:
•Drain the fuel tank (see “Draining the Fuel Tank” in the “Maintenance” section).
•Disconnect the spark plug cap from the spark plug.
•Do not obstruct any ventilation openings.
•Keep the engine in a cool dry area.
15

SPECIFICATIONS
Displacement 173cc
Max. Output 3.2 KW/3600RPM
Max. Torque 9 N·m/2500RPM
Engine Type Vertical Single Cylinder 4 stroke OHV
Meets EPA phase III and CARB compliant
Cooling System Forced air cooled
Fuel Type 87+ octane unleaded gasoline
Capacity 0.3 Gallon
Engine Oil
Type SAE 10W-30 above 32° F
5W-30 at 32° F or below
Capacity 0.6 Quart
Lubrication System Forced Splash
Run Time @ 50% Load
with full tank
40 minutes
Sound Level at 22 feet 104 dB
Bore x Stroke 70 mm x 45 mm
Compression Ratio 8.5:1
Rotation viewed from PTO
(power takeoff - the output
shaft)
Counterclockwise
Shaft
Shaft 7/8″x 3.16″
Keyway 3/16″(4.76 mm)
End
Tapped
3/8″- 24 UNF
Spark Plug Type NGK: BP-6ES, Torch: F6TC/F7RTC
Gap 0.7-0.8 mm
Valve
Clearance
Intake 0.10-0.15 mm
Exhaust 0.15-0.20 mm
Idle Speed 1,800 ± 50 RPM
Dimensions 17.9x15x16.5 inches
Weight 30.8 lbs
16

MOUNTING HOLE DIAGRAM
17