Ardisam Viper Engines 31321 Installation and operation manual

ENGINES
OM31321
Rev. 11/27/09
© 2009 Ardisam, Inc.
All Rights Reserved. Printed in USA.
ARDISAM
.com
OPERATING & MAINTENANCE
INSTRUCTIONS
173CC 4-CYCLE ENGINE

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 2
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
INTRODUCTION
Thank You . . .
for purchasing a Viper engine from Ardisam, Inc. We have worked to
ensure that our product meets high standards for usability and durability.
With proper care, your engine will provide many years of excellent service.
Please take the time to read this manual carefully to learn how to correctly
operate and maintain your Viper engine. Due to continuous efforts to per-
fect our products, certain procedures and specifications are subjected to
change without notice. Congratulations on your investment in quality.
CONTENTS
Introduction ................................................................................................ 2
Warranty/Registration..............................................................................3-4
General Safety Precautions ....................................................................5-6
Engine Components................................................................................... 7
Pre-Operation Procedures ......................................................................8-9
Engine Operation ..................................................................................... 10
Maintenance............................................................................................. 11
Engine Maintenance ........................................................................... 12-13
Service and Troubleshooting...............................................................14-15
Parts Explosion/Parts List ...................................................................16-18
FEDERAL EMISSION INFORMATION
Ardisam, Inc. warrants to the retail purchaser, that this small, off-
road engine was designed, built and equipped to conform at the
time of initial sale to all applicable regulations of the U.S. Environ-
mental Protection Agency (EPA).
SPECIFICATIONS
Engine Type 4-Stroke Gasoline Engine with Vertical Shaft & Recoil Start
Air Cooled/Engine Model: 31321
Displacement 173 cc
Torque 6.5 ft. lbs. at 3,000 RPM
Fuel Tank Capacity 0.52 Gal.
Engine Oil Capacity 27 oz.
Air Cleaner Type Cartridge Type
Weight 38 lbs.
IMPORTANT!
This product requires oil and fuel to be added before starting. Attempting to start
the Engine without oil WILL ruin the Engine and void the warranty.
*The emission control system for this Engine is warranted for standards set by
the U.S. Environmental Protection Agency. For warranty information, refer to
pages 3-4 of the manual.

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 3
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
WARRANTY
Ardisam, Inc., Manufacturing Company warrants its Viper Engines under a two year limited warranty to be free from defects in materi-
als and workmanship for the service life of the product not to exceed twenty four consecutive months from the date of purchase for
consumer applications. As an Ardisam Viper small engine owner, you are responsible for executing proper maintenance listed in your
Operating and Maintenance Instructions. The warranty period begins on the date of purchase by the first retail consumer or com-
mercial end user, and continues for the period of time stated above.
This warranty applies only to products which have not been subjected to negligent use, misuse, alteration, accident, unauthorized parts,
failure to use proper fuel and oil, or if repairs have been performed at non-authorized service centers. This warranty supersedes all
other warranties either expressed or implied and all other obligations or liabilities on our part. Ardisam, does not assume, and does not
authorize any other person to assume for us, any liability in connection with the sale of our products. To be at "No Charge," however,
warranty work must be sent directly to Ardisam, Inc. or one of our authorized service centers and performed by them. To obtain war-
ranty service and replacement instructions, contact our customer service department at 800-345-6007 Monday through Friday from
8 a.m. to 5 p.m. or visit www.ardisam.com. Ardisam will at no charge, repair or replace, at their discretion, any defective part which
falls under the conditions stated above. Ardisam retains the right to change models, specifications and price without notice.
Viper Engines, A Division of Ardisam, Inc.
1160 Eighth Avenue; P.O. Box 666
Cumberland, Wisconsin 54829
800-345-6007 · Fax [phone]
E-mail: inf[email protected]
REGISTRATION, SERVICE AND MAINTENANCE LOG
Record the model number and serial number in the space provided for easy reference. Fill out and mail the registration card located in the parts
packet or register online at www.ardisam.com. The Engine Serial Number is located under the fuel tank.
OWNERSHIP RECORDS
Owner’s Name:
Owner’s Address:
City: State/Province: Zip Code/Postal Code:
Model Number: 31321 Serial Number:
Date of Purchase:
Notes:
The Engine Serial Number is located under the fuel tank.

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 4
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
Explanation of Emissions Control
Warranty Provisions
Viper Engines are designed, built and equipped to meet all EPA
requirements. It warrants that it is free from defects in material and
workmanship that could cause failure to the warranted part; and that
it is identical in all material respects to the engine described in the
manufacturer's application for certification.When a warrantable condi-
tion exists, Viper will repair your engine at no cost to you, including
parts and labor. The engine emissions label will indicate certification
information. If the purchaser is in need of a warrantable repair and
is not within 100 miles distance from an Ardisam authorized repair
center, Ardisam will pay for shipping costs to and from an authorized
Ardisam repair center.
Listed below are the parts covered by the emissions control systems war-
ranty. Some parts listed below may require scheduled maintenance and
are warranted up to the first scheduled replacement point for that part.
Coverage under this warranty includes only the parts listed below (the
emission and evaporation control systems) if so equipped:
• Air Filter Assembly (only to the first scheduled replacement point)
• Fuel Filter (only to the first scheduled replacement point)
• Carburetor
• Fuel Lines, Fuel Line Fittings and Clamps
• Fuel Metering Valve (if equipped)
• Evaporative System (if equipped)
- Canister (if equipped)
- Canister filter (if equipped)
- Vapor hose (if equipped)
- Orifice connector (if equipped)
-Fuel tank
-Fuel cap
-Primer bulb canister (if equipped)
• Spark Plugs
• Magneto Ignition System
• Muffler Assembly
LIMITATIONS
The Emission Control Systems Warranty shall not cover any of the
following:
a) Repair or replacement required because of misuse or neglect,
improper maintenance, repairs improperly performed or
replacements not conforming to Ardisam, Inc. specifications that
adversely affect performance and/or durability and alterations
or modifications not recommended or approved in writing by
Ardisam, Inc.
b) Replacement of parts and other services and adjustments
necessary for required maintenance at or after the first sched-
uled replacement point;
c) Consequential damages such as loss of time, inconvenience,
loss of use of the engine or equipment, etc.
d) Diagnosis and inspection fees that do not result in eligible
warranty service being performed; and
e) Any add-on or modified part, or malfunction of authorized parts
due to the use of add-on or modified parts.
The warranty on emissions-related parts is as follows:
• Any warranted part that is not scheduled for replacement as required
maintenance in the owner's manual supplied, is warranted for the
warranty period stated above. If any such part fails during the period
of warranty coverage, that part will be repaired or replaced at no
charge to the owner. Any such part repaired or replaced under the
warranty will be warranted for the remaining warranty period.
• Any warranted part that is scheduled only for regular inspection
in the owner's manual supplied, is warranted for the warranty
period. Any such part repaired or replaced under warranty will be
warranted for the remaining warranty period.
• Any warranted part that is scheduled for replacement as required
maintenance in the owner's manual supplied, is warranted for the
period of time prior to the first scheduled replacement point for that
part. If the part fails prior to the first scheduled replacement, the part
will be repaired or replaced at no charge to the owner. Any such
part repaired or replaced under warranty will be warranted for the
remainder of the period prior to the first scheduled replacement point
for the part.
• Add on or modified parts that are not exempted by the Air
Resources Board may not be used. The use of any nonexempted
add on or modified parts by the owner will be grounds for
disallowing a warranty claim. The manufacturer will not be liable
to warrant failures of warranted parts caused by the use of a
nonexempted add on or modified part.
These items will be covered for a period of two years from the
date of the original purchase. Viper warrants that: the compo-
nents are designed, built and equipped so as to conform with all
applicable regulations adopted by the EPA; that they are free from
defects in material and workmanship that could cause failure to
the engine or other; and that the components used are identical in
all material respects to the engine described in the manufacturer's
application for certification. The warranty period begins on the
date the engine is originally purchased.
MAINTENANCE AND REPAIR REQUIREMENTS
The owner is responsible for the proper use and maintenance
of the engine. Ardisam, Inc. recommends that all receipts and
records covering the performance of regular maintenance be
retained in case questions arise. If the engine is resold during the
warranty period, the maintenance records should be transferred
to each subsequent owner. Ardisam, Inc. reserves the right to
deny warranty coverage if the engine has not been properly
maintained; however, Ardisam, Inc. may not deny warranty repairs
solely because of the lack of repair maintenance or failure to keep
maintenance records.
Normal maintenance replacement or repair of emission control devices
and systems may be performed by any repair establishment or indi-
viduals; however, warranty repairs must be performed by an Ardisam
authorized service center. Any replacement parts or service that is
equivalent in performance and durability may be used in non-warranty
maintenance or repairs, and shall not reduce the warranty obligations
of the engine manufacturer.

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 5
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
GENERAL SAFETY PRECAUTIONS
Please read this section carefully. Operate the engine according to the
safety instructions and recommendations outlined here and inserted
throughout the text. Anyone who uses this engine must read the instruc-
tions and be familiar with the controls.
Owner’s Responsibility:
It is the owner’s responsibility to accurately assemble the engine for safe
and effective use.
• Read and follow all safety instructions.
• Carefully follow all assembly instructions.
• Maintain the engine according to directions and schedule included in
this operator’s manual.
• Ensure that anyone who uses this engine is familiar with all controls
and safety precautions.
SIGNAL WORDS
A signal word alerts you to potential hazards that could harm
you or others. Each signal word is preceded by the safety alert
symbol followed by the word DANGER, WARNING, CAUTION or
IMPORTANT.
Each signal word will make you aware of what the hazard is, what can
happen, and what you can do to prevent or decrease injury occur-
rence.
WARNING
!
WARNING INDICATES YOU CAN BE KILLED OR
SERIOUSLY INJURED IF THE SAFETY INSTRUC-
TIONS THAT FOLLOW THIS SIGNAL WORD ARE
NOT OBEYED.
DANGER
!
DANGER INDICATES YOU WILL BE KILLED OR
SERIOUSLY INJURED IF THE SAFETY INSTRUC-
TIONS THAT FOLLOW THIS SIGNAL WORD ARE
NOT OBEYED.
CAUTION
!
CAUTION INDICATES YOU CAN OR YOUR EQUIP-
MENT CAN BE HURT IF THE SAFETY INSTRUC-
TIONS THAT FOLLOW THIS SIGNAL WORD ARE
NOT OBEYED.
IMPORTANT
INDICATES HELPFUL INFORMATION FOR PROP-
ER ASSEMBLY, OPERATION, OR MAINTENANCE
OF YOUR ENGINE.

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 6
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
PRECAUTIONS
WARNING:
FUEL FILLING PRECAUTIONS
• FUEL AND FUEL VAPORS ARE HIGHLY FLAMMA-
BLE.
• NEVER FILL GAS TANK INDOORS OR IN A POORLY
VENTILATED AREA.
• TURN ENGINE OFF AND LET COOL BEFORE RE-
MOVING GAS CAP.
• DO NOT OVERFILL GAS TANK. IF FUEL SPILLAGE
OCCURS, WIPE AWAY CAREFULLY AND ALLOW
FUEL TO DRY BEFORE STARTING ENGINE.
• PREVENT FIRE AND EXPLOSION CAUSED BY STAT-
IC ELECTRIC DISCHARGE. USE ONLY NON-METAL,
PORTABLE FUEL CONTAINERS APPROVED BY
THE UNDERWRITER’S LABORATORY(U.L.) OR THE
AMERICAN SOCIETY FOR TESTING & MATERIALS
(ASTM).
• NEVER POUR FUEL OUT OF ENGINE GAS TANK.
• NEVER ALLOW CHILDREN TO FILL THE GAS TANK.
ADULTS ONLY.
• NEVER ALLOW YOURSELF, OR ANYONE UNDER
THE INFLUENCE OF DRUGS OR ALCOHOL,TO FILL
GAS TANK.
• GAS CAP MUST BE PROPERLY SECURED BEFORE
AND DURING OPERATION.
• REFRAIN FROM SMOKING AND STAY AWAY FROM
OPEN FLAMES AND SPARKS WHEN REFUELING.
!
WARNING:
EXHAUST PRECAUTIONS
• DO NOT INHALE EXHAUST FUMES. THEY GIVE OFF
CARBON MONOXIDE, AN ODORLESS, COLORLESS,
DEADLY GAS.
• USE EXTREME CARE WHEN RUNNING ENGINE
NEAR PEOPLE OR ANIMALS. ALWAYS POINT EX-
HAUST AND MUFFLER IN A SAFE DIRECTION.
• NEVER RUN ENGINE IN AN ENCLOSED OR PAR-
TIALLY ENCLOSED AREA. EXAMPLES INCLUDE:
BUILDINGS THAT ARE ENCLOSED ON ONE OR
MORE SIDES, CAR PORTS OR BASEMENTS.
• ALWAYS MAKE SURE EXHAUST PIPE IS FREE OF
FOREIGN OBJECTS.
!
WARNING:
FIRE & BURN PROTECTION
• KEEP ALL SPARKS, SMOKING MATERIALS, AND
OPEN FLAMES AWAY FROM ENGINE.
• DO NOT USE ENGINE AROUND DRY BRUSH, CLOTH
RAGS, OR OTHER FLAMMABLE MATERIALS.
• BE CAREFUL OF HOT PARTS. THE MUFFLER
GUARD AND OTHER PARTS BECOME EXTREMELY
HOT DURING AND IMMEDIATELY AFTER USE. HOT
PARTS CAN CAUSE SEVERE BURNS.
• ALWAYS KEEP MATERIALS AND DEBRIS CLEAR
OF MUFFLER GUARD AND OTHER HOT ENGINE
PARTS.
• NEVER OPERATE THE ENGINE WITHOUT THE MUF-
FLER GUARD IN PLACE.
!
WARNING:
OTHER SAFETY PRECAUTIONS
• STAY AWAY FROM ROTATING PARTS. PLACE PRO-
TECTIVE COVERS OVER ROTATING PARTS.
• DO NOT CARRY OR REMOVE ENGINE WHILE IN OP-
ERATION.
• OPERATE THE ENGINE ONLY ON LEVEL AND STA-
BLE SURFACES.
!
WARNING:
ENGINE REPAIR PRECAUTIONS
• BEFORE WORKING ON ENGINE, ENGINE SHOULD
BE OFF AND COOL.
• ALWAYS DISCONNECT THE SPARK PLUG WIRE
FROM THE SPARK PLUG.
• SECURE DISCONNECTED SPARK PLUGWIRE AWAY
FROM SPARK PLUG AND ANY METAL OBJECTS
TO AVOID ARCING (HAZARDOUS UNINTENTIONAL
CONNECTION).
• CHECK ALL PARTS THAT WERE REPAIRED OR RE-
MOVED TO ENSURE SECURE AND PROPER FIT.
• USE ONLY ORIGINAL VIPER EQUIPMENT AND
PARTS.
!

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 7
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
ENGINE COMPONENTS
MODEL 31321 173CC HORIZONTAL SHAFT
This is a 4-cycle air cooled engine. This 173cc engine utilizes a
vertical shaft output.
Note: Figure 1 pictures may vary slightly from the actual
model.
WARNING
!
DO NOT REFUEL WHILE SMOKING, NEAR OPEN
FLAME, OR OTHER POTENTIAL HAZARDS.
FUEL IS HIGHLY FLAMMABLE AND MUST BE HAN-
DLED WITH CARE. NEVER FILL THE TANK WHEN
THE ENGINE IS HOT OR RUNNING. ALWAYS MOVE
OUTDOORS TO FILL THE TANK.
IMPORTANT
ENGINE IS SHIPPED FROM FACTORY WITHOUT
OIL. YOU MUST ADD ENGINE OIL BEFORE START-
ING ENGINE. IF ENGINE IS STARTED WITHOUT
OIL, ENGINE MAY BE DAMAGED BEYOND REPAIR
AND WILL NOT BE COVERED BY WARRANTY.
FIGURE 1
Fuel Filler Cap Oil Dipstick
Muffler
Fuel Tank
Starting Handle
Spark Plug
Air Cleaner

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 8
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
PRE-OPERATION PROCEDURES
PRE-OPERATION INSPECTION
1. Examine underneath and around engine for signs of oil or fuel
leaks.
2. Inspect fuel hoses and joints for tightness and fuel seepage.
3. Look for signs of engine damage.
4. Check that all guards and shields are in place, and all screws,
nuts and bolts are tightened.
5. Eliminate excessive debris around muffler and recoil starter.
6. Inspect the air filter component for air restrictions that may
reduce engine performance.
CHECKING & ADDING OIL
NOTE: Engine oil is a key factor in deciding the engine’s per-
formance. Do not apply engine oil with additives or 2-stroke
gasoline engine oil, as they haven’t enough lubrication, which
may shorten the engine’s service life.
Check the engine with it stopped on a level ground. Engine oil
recommended: SAE-30. SEE FIGURE 2. As viscosity varies with
regions and temperatures, so the lubricant has to be selected in
accordance with our recommendation.
OIL CAPACITY
27 oz.
CHECK
Procedure in checking oil level should be taken as follows: SEE
FIGURE 3
1. Ensure that the engine is stopped on a level ground.
2. Remove dipstick and clean it.
3. Reinsert the dipstick into the oil filler without screwing in, and
then withdraw it to check oil level.
4. If the oil level is too low, add recommeded engine oil to the up-
per level on the dipstick. SEE FIGURE 3
5. Reinstall the dipstick.
NOTE: Running with insufficient engine oil may damage the
engine severely.
CAUTION
!
FOR THE SAFETY OF THE USER, AND TO MAXI-
MIZE THE LIFE OF THE ENGINE, IT IS CRUCIAL TO
TAKE TIME TO CHECK THE CONDITION OF THE
ENGINE. PROBLEMS MUST BE CORRECTED BE-
FORE OPERATING.
AVOID INJURY! ENGINE OIL IS HAZARDOUS TO
YOUR HEALTH. DISPOSE OF OIL APPROPRIATELY.
USE A SAFE DISPOSAL/RECYCLING CENTER.
WARNING
!
DO NOT ATTEMPT TO START ENGINE IN THE FOL-
LOWING WAYS:
• DO NOT USE STARTING FLUID.
• DO NOT SPRAY FLAMMABLE LIQUIDS OR VA-
PORS INTO AIR CLEANER, CARBURETOR OR
SPARK PLUG CHAMBER.
• DO NOT REMOVE SPARK PLUG AND PULL
ON STARTER ROPE. FLAMMABLE FUEL CAN
SPRAY OUT AND IGNITE FROM A SPARK FROM
SPARK PLUG.
DO NOT REFUEL WHILE SMOKING, NEAR OPEN
FLAME, OR OTHER POTENTIAL HAZARDS.
FUEL IS HIGHLY FLAMMABLE AND MUST BE HAN-
DLED WITH CARE. NEVER FILL THE TANK WHEN
THE ENGINE IS HOT OR RUNNING. ALWAYS MOVE
OUTDOORS TO FILL TANK.
IMPORTANT
ENGINE IS SHIPPED FROM FACTORY WITHOUT
OIL. YOU MUST ADD ENGINE OIL BEFORE START-
ING ENGINE.
FIGURE 3
FIGURE 2

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 9
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
WARNING
FUEL IS HIGHLY FLAMMABLE AND MUST BE HAN-
DLED WITH CARE. NEVER FILL THE TANK WHEN
THE ENGINE IS HOT OR RUNNING. ALWAYS MOVE
OUTDOORS TO FILL THE TANK.
!
drain plug
CHECKING & FILLING GAS TANK
FUEL AND FUEL TANK
The engine must run on unleaded gasoline with an octane number
over 86. Using unleaded gasoline will decrease the possibility of
producing carbon deposits and prolong the engine’s service life.
NOTE: Do not use E85, serious engine damage may result.
1. Never apply used or contaminated gasoline or a mixture of
gasoline and engine oil. Make sure the fuel is free of dirt and
water.
NOTE: Handle fuel with care because it can damage plastic
and painted surfaces.
2. Fuel tank capacity: 0.52 gal.
NOTE: 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 gasoline is stored or where the fuel tank is
refueled.
Do not overfill the tank (there should be no fuel in the filler
neck). After refueling, make sure the fuel tank cap is screwed
on.
Be careful not to spill fuel when refueling. Spilled fuel vapor
may ignite. If any fuel is spilled, make sure the area is com-
pletely dried before starting the engine.
Avoid repeated or prolonged contact with skin or breathing of
fuel vapor.
Keep out of reach of children.

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 10
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
ENGINE OPERATION
REVIEW SECTION “PRE-OPERATION INSPECTION” BEFORE
STARTING ENGINE.
STARTING & STOPPING ENGINE
ENGINE STARTING
1. Set the fuel shutoff to “ON” SEE FIGURE 5
2. Push the throttle lever to choke position.
NOTE: If the engine is hot, closing the choke may not be
necessary.
3. Start the engine as follows: Pull the starting rope handle up
slightly until feeling resistance, and then make a rapid pull.
OPERATION
1. After engine starts, push the choke lever back to “HIGH” or
“FAST”.
2. Set the throttle lever in proper position to ensure the engine
runs at preset RPM (high speed)
STOP
1. Move throttle to stop position.
WARNING
!
CARBON MONOXIDE GAS IS TOXIC. INHALATION
CAN CAUSE UNCONSCIOUSNESS AND DEATH.
NEVER LEAVE ENGINE RUNNING WHILE UNAT-
TENDED.
DO NOT ATTEMPT TO START ENGINE IN THE FOL-
LOWING WAYS:
• DO NOT USE STARTING FLUID.
• DO NOT SPRAY FLAMMABLE LIQUIDS OR VA-
PORS INTO AIR CLEANER, CARBURETOR OR
SPARK PLUG CHAMBER.
• DO NOT REMOVE SPARK PLUG AND PULL
ON STARTER ROPE. FLAMMABLE FUEL CAN
SPRAY OUT AND IGNITE FROM A SPARK FROM
SPARK PLUG.
CAUTION
!
DO NOT STOP ENGINE BY MOVING CHOKE CON-
TROL TO CHOKE. BACKFIRE, ENGINE DAMAGE,
OR FIRE MAY OCCUR.
FIGURE 5
Fuel Shutoff

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 11
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
MAINTENANCE
Please read the maintenance schedule, and observe these
recommended care operating intervals to extend the life of
your engine.
Good maintenance is essential for safe, economical, and
trouble-free operation. It will also help reduce air pollution. To help
you properly care for your engine, the following pages include
a maintenance schedule, routine inspection procedures, and
simple maintenance procedures using basic hand tools. Other
service tasks that are more difficult, or require special tools, are
best handled by professionals and are normally performed by a
technician or other qualified mechanic.
Maintenance, replacement or repair of the emissions control
devices and systems may be performed by any non-road engine
repair establishment or individuals. However, items must be
serviced by an authorized dealer to obtain "no charge" emis-
sions control service.
The maintenance schedule applies to normal operating condi-
tions. If you operate your engine under unusual conditions,
such as sustained high-load or high-temperature operation, or
use in unusually wet or dusty conditions, consult your servic-
ing dealer for recommendations applicable to your individual
needs and use.
CAUTION
!
TO PREVENT ACCIDENTAL STARTING:
AVOID INJURY! ENGINE MUST BE TURNED OFF
AND COOL AND SPARK PLUG WIRE MUST BE RE-
MOVED FROM SPARK PLUG BEFORE CHECKING
AND ADJUSTING ENGINE OR EQUIPMENT.
AVOID INJURY! TEMPERATURE OF MUFFLER AND
NEARBY AREAS MAY EXCEED 150° F (65° C).
AVOID THESE AREAS.
AVOID INJURY! CHECK ENGINE OFTEN FOR
LOOSE NUTS AND BOLTS. KEEP THESE ITEMS
TIGHTENED.
MAINTENANCE ITEM
Every 8 hours
(daily)
Every 50 hours
or seasonally
Every 100 hours
or seasonally Yearly
Clean Engine and
Check Bolts & Nuts
X
Engine Oil Check X
(See Lubrication section) Change * (initial 5 hours) X
Air Filter Check X X
(See Air Filter section) Clean ** (20 hours)
Replace X
Spark Plug (Gap .030”) Check-Adjust X
(See Spark Plug section) Replace X
Fuel Filter Clean *** X
(See Fuel Filter section) Replace
* Perform initial oil change after first 5 hours of operation, then every 50 hours or every season
** Service more frequently under dusty conditions
*** These items should only be performed by a mechanically proficient person or by the servicing dealer
Failure to follow this maintenance schedule could result in nonwarrantable failures.

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 12
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
ENGINE MAINTENANCE
LUBRICATION
Choose engine oil that meets or surpasses the latest API service
classification. For temperatures higher than 32° F, use SAE 30 or
SAE 10W-30 motor oil. Use SAE 5W-30 or SAE 10W if tempera-
tures are below 32° F.
NOTE: Do not use SAE 10W-40 motor oil.
OIL MAINTENANCE
After the first five hours of operating a new Viper engine the oil
should be replaced, and every 50 hours of operating time thereaf-
ter. The oil should be changed every 25 hours if used under severe
conditions, such as in high temperatures or under heavy loads,
otherwise changed weekly. Check oil periodically; do not overfill!
CHANGING OIL
Be sure the engine is not operating and is located on a level
surface before checking or refilling oil. Engine should be warm for
easy removal of oil.
1. Detach spark plug wire and move away from spark plug. SEE
FIGURE 11.
2. Remove oil drain plug and empty oil into suitable oil container.
Dispose of oil properly. SEE FIGURE 12.
3. Reinstall drain plug. Remove dipstick (if applicable) or oil fill
cap. SEE FIGURE 2.
4. Fill with appropriate oil to “FULL” or top line of dipstick.
5. Reinsert dipstick or oil fill cap and tighten.
AIR FILTER
• Never run engine without air filter properly installed. Added
wear and engine failure may occur if air filter is not installed on
engine.
• Service air filter every 3 months or after 20 hours of operation.
Clean filter daily in extremely dusty conditions.
• Replace air filter yearly.
CAUTION
!
TO PREVENT ACCIDENTAL STARTING
AVOID INJURY! ENGINE MUST BE TURNED OFF
AND COOL AND SPARK PLUG WIRE MUST BE RE-
MOVED FROM SPARK PLUG BEFORE CHECKING
AND ADJUSTING ENGINE OR EQUIPMENT.
OIL IS HAZARDOUS WASTE
AVOID INJURY! ENGINE OIL IS HAZARDOUS TO
YOUR HEALTH. DISPOSE OF OIL APPROPRIATELY.
USE A SAFE DISPOSAL/RECYCLING CENTER.
FIGURE 11
air filter cover
wing nut
spark plug
spark plug
wire
FIGURE 12
Drain Plug

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 13
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
SPARK PLUG
The recommended spark plug is a Torch F6TC which cross refer-
ences to an NGK BPR6ES or Champion N9YC.
CHECKING AND CHANGING SPARK PLUG
1. Check spark plug every 50 operating hours.
2. Disconnect the spark plug cap, and clean any debris form
around the spark plug area.
3. Remove spark plug and replace if any of the following occur;
pitted electrodes, burned electrodes, cracked porcelain, or de-
posits around electrodes.
4. After analysis, seat spark plug and tighten with spark plug
wrench to compress the sealing washer. SEE FIGURE 11.
• Reinstall original spark plug, tighten additional 1/2 turn.
• Installing new spark plug, adjust spark plug gap to .030” and
tighten additional 1/8 – 1/4 turn .
NOTE: Loose spark plug may overheat and damage
engine. Over tightened spark plug may damage threads in
the cylinder head.
SPARK PLUG MAINTENANCE
Spark plug should be removed, cleaned and gap adjusted after ap-
proximately fifty hours of operating time.
NOTE: A sand blaster should not be used to clean spark
plugs. Microscopic particles remaining in the plug may
score the engine cylinder during operation. Use solvent
and a wire brush to clean the plug and compressed air to
blow out completely.
CARBURETOR
• Never tamper with factory setting of the carburetor.
• Contact your service provider or Ardisam, Inc. if adjustment is
needed.
WARNING
!
FUEL IS HIGHLY FLAMMABLE AND MUST BE HAN-
DLED WITH CARE. NEVER FILL THE TANK WHEN
THE ENGINE IS HOT OR RUNNING. ALWAYS MOVE
OUTDOORS TO FILL GAS TANK.

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 14
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
SERVICE AND TROUBLESHOOTING
SERVICE INFORMATION
At Ardisam, we build quality and durability into the design of our
products. Nevertheless, no amount of careful design by us, or thor-
ough maintenance by you, can guarantee a repair-free life for your
engine. Most repairs will be minor and easily fixed by following the
suggestions in the troubleshooting guide of this section.
This section will help you pinpoint the causes of common problems
and identify remedies.
For more complicated repairs you may want to rely on your retailer,
an authorized mechanic or Ardisam, Inc. (contact your retailer
for a list of authorized mechanics in your area). A parts catalog
is included in this section. We will always be glad to answer any
questions you encounter or find suitable assistance to meet your
needs. To order parts or inquire about our warranty call, write or
browse our website at the address found below under the section
“ordering repair parts.”
ORDERING REPAIR PARTS
Parts can be obtained from the store where your engine was pur-
chased or direct from the factory. To order from the factory, call or
write to:
Ardisam, Inc.
1160 Eighth Avenue, Cumberland, WI 54829
Phone [phone] Fax [phone]
1-800-345-6007
Email: [e-mail]
www.ardisam.com
Please include the following information with your order:
1. Part numbers
2. Part description
3. Quantity
4. Model number and serial number
CAUTION
!
PRACTICE SAFETY AT ALL TIMES. ENGINE MUST
BE TURNED OFF AND ALLOWED TO COOL AND
SPARK PLUG WIRE MUST BE DISCONNECTED
BEFORE ATTEMPTING ANY MAINTENANCE OR
REPAIR.

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 15
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
TROUBLESHOOTING
PROBLEM POSSIBLE CAUSE REMEDY/ACTION
Engine will not start 1. Power switch off 1. Flip switch to ON position
2. Spark plug wire disconnected 2. Connect spark plug wire to spark plug
3. Out of fuel 3. Refuel
4. Spark plug wet, faulty or improperly
gapped
4. Clean, replace or gap sparkplug
Engine runs rough, floods during opera-
tion
1. Dirty air filter 1. Clean or replace air filter
2. Choke partially engaged 2. Turn off choke
3. Carburetor out of adjustment 3. Call factory
Engine is hard to start 1. Stale fuel 1. Drain old fuel and replace with fresh.
Use gas stabilizer at end of season
2. Spark plug wire loose 2. Make sure spark wire is securely at-
tached to spark plug
3. Dirty carburetor 3. Clean carburetor, use gas stabilizer,
new gas can
Engine misses or lacks power 1. Clogged gas tank 1. Remove and clean
2. Clogged air filter 2. Clean or replace
3. Improper carburetor adjustment 3. Call factory
4. Spark plug dirty, improper gap, or
wrong type
4. Replace spark plug and adjust gap to
.030”
Engine runs, then quits 1. Gas cap not venting 1. Check cap for venting
Contact service provider if above remedies fail.

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 16
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
173cc VERTICAL SHAFT ENGINE PARTS
Note: Some parts are listed and shown for illustration purposes only, and are not available individually as
replacement parts.

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 17
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
1
37
35 36
27
27
31
29
31
31
28
27
30
27
25
24
32
30
22
23
33
30
14
14
12
20
11
18
18
8
17
16
13
14
12
9
7
10
6
4
3
22
26
5
2
21
19
22
31
31
19
34
15
38
16
16
32
9
9
9
39
ENGINE GASKET KIT
40
173cc VERTICAL SHAFT ENGINE PARTS EXPLOSION
Note: Duplicate key numbers indicates part is only available as a service kit.

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 18
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
6.0 HP VERTICAL SHAFT ENGINE PARTS LIST
KEY
NO.
PART
NO. DESCRIPTION QTY.
1 913142 RECOIL STARTER ASSEMBLY 1
2 913249 FLYWHEEL NUT 1
3 913250 STARTER FLANGE 1
4 913251 FLYWHEEL FAN 1
5 913207 BOLT M6 X 20 1
6 913205 GAS CAP ASSEMBLY 1
7 913206 FUEL TANK 1
8 913130 BOLT M6 X 28 1
9 913133 DIPSTICK AND TUBE ASSEMBLY 1
10 913101 BREATHER SERVICE KIT 1
11 913159 FLYWHEEL KEY 1
12 913208 SPACER SERVICE KIT 4
13 913212 FUEL SHUTOFF AND FILTER 1
14 913149* RECOIL STUD SERVICE KIT 1
15 913155** ENGINE SHORTBLOCK W/GASKET
SET
1
16 913145* MUFFLER SERVICE KIT 1
17 913124 MUFFLER NUT 2
18 913128 DRAIN PLUG ASSEMBLY 1
19 913129* OIL SEAL SERVICE KIT 1
20 913136 MUFFLER STUD AND NUT
SERVICE KIT
1
21 913137 SPARK PLUG 1
22 913144* VALVE COVER AND GASKET
SERVICE KIT
1
23 913147 CARB STUD 2
24 913158 CARB REPAIR SERVICE KIT 1
KEY
NO.
PART
NO. DESCRIPTION QTY.
25 913187 AIR CLEANER GASKET 1
26 913219 NUT AIR FILTER HOUSING M6 2
27 913218* AIR FILTER BASE SERVICE KIT 1
28 913216 AIR FILTER 1
29 913215 AIR CLEANER COVER 1
30 913114 BREATHER AND FUEL LINE
SERVICE KIT
1
31 913150 GOV LINKAGE/SPRING REPAIR
SERVICE KIT
1
32 913189 HEAT INSULATOR AND GASKET 1
33 913146 CYLINDER HEAD ASSEMBLY 1
34 913170 PUSHROD SERVICE KIT 1
35 913253 IGNITION COIL 1
36 913236 SPEED CONTROL ASSEMBLY 1
37 913231 ACORN NUT M6 3
38 913186 CARB COMPLETE 1
39 31321 REPLACEMENT ENGINE 1
40 913178 ENGINE GASKET SET 1
*Duplicate key numbers indicates part is only available as a
service kit.
**Limited availability

ENGINES
ARDISAM
.com
Ardisam, Inc. Page 19
800-345-6007
OPERATING AND MAINTENANCE INSTRUCTIONS
173cc Vertical Shaft Engine
NOTES
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________

VIPER Engines, Manufactured by Ardisam, Inc.
1160 Eighth Avenue
Cumberland, Wisconsin 54829
800-345-6007 · Fax [phone]
Email: inf[email protected]
ARDISAM
.com
ENGINES