Briggs & Stratton 120000 Installation and operation manual

Document: - page 1 (Black)
Screen angle and frequency: 45.0000, 150.0000
Model Series
Covered in
This Manual
110000
120000
Operating & Maintenance
Instructions
Model Type Code
Month Day Year
Note: General Model Series numbers noted above are inclusive of the specific model
number found on your engine. To get replacement parts or technical assistance in
the future, write your engine Model, Type, Code and date of purchase here.
TABLE OF CONTENTS
Safety 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Information 6. . . . . . . . . . . . . . . . . . . . . . . .
Oil 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel and Starting Information 8. . . . . . . . . . . . . . .
Starting and Stopping 9-10. . . . . . . . . . . . . . . . . . .
Maintenance 11-13. . . . . . . . . . . . . . . . . . . . . . . . .
Adjustments 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts and Service & Storage 15-16. . . . . . . . . . . .
Warranty Information 17. . . . . . . . . . . . . . . . . . . . .
WARNING
Briggs & Stratton does not approve or authorize the use of
these engines on 3-wheel All Terrain Vehicles (ATVs), motor
bikes, fun/recreational go-karts, aircraft products or vehicles
intended for use in competitive events. Use of these engines in
such applications could result in property damage, serious
injury (including paralysis), or even death.
Need assistance? Go to www.briggsandstratton.com
for detailed information regarding
Briggs & Stratton engines.
Or call, 1-800-233-3723, (U.S.A. and Canada)
to hear a menu of pre-recorded messages
offering engine maintenance information.
PRINTED IN U.S.A. Copyright 2003 by Briggs & Stratton Corporation FORM NO. 275749-8/03

2
The Power That Works For You.
Look For Relevant Emissions Durability Period and Air Index Information On
Your Engine Emissions Label
Engines that are certified to meet the California Air Resources Board (CARB) Tier 2 Emission Standards must display information regard-
ing the Emissions Durability Period and the Air Index. Briggs & Stratton makes this information available to the consumer on our emission
labels. The engine emission label will indicate certification information.
TheEmissions Durability Period describes the number of hours of actual running time for which the engine is certified to be emissions
compliant, assuming proper maintenance in accordance with the Operating & Maintenance Instructions. The following categories are
used:
Moderate: Engine is certified to be emission compliant for 125 hours of actual engine running time.
Intermediate: Engine is certified to be emission compliant for 250 hours of actual engine running time.
Extended: Engine is certified to be emission compliant for 500 hours of actual engine running time.
For example, a typical walk-behind lawn mower is used 20 to 25 hours per year. Therefore, the Emissions Durability Period of an
engine with an intermediate rating would equate to 10 to 12 years.
The Air Index is a calculated number describing the relative level of emissions for a specific engine family. The lower the Air Index,
the cleaner the engine. This information is displayed in graphical form on the emissions label.
After July 1, 2000, Look For Emissions Compliance Period On
Engine Emissions Compliance Label
After July 1, 2000 certain Briggs & Stratton engines will be certified to meet the United States Environmental Protection Agency (USEPA)
Phase 2 emission standards. For Phase 2 certified engines, the Emissions Compliance Period referred to on the Emissions Compliance
label indicates the number of operating hours for which the engine has been shown to meet Federal emission requirements. For engines
less than 225 cc displacement, Category C = 125 hours, B = 250 hours and A = 500 hours. For engines of 225 cc or more, Category
C = 250 hours, B = 500 hours and A = 1000 hours.
The displacement of model series 110000 engine is 167 cc, and model series 120000 engine is 190 cc.
This is a generic representation
of the emission label typically
found on a certified engine.

3
BEFORE OPERATING ENGINE THE OPERATING & MAINTENANCE
INSTRUCTIONS CONTAIN SAFETY
INFORMATION TO:
•Make you aware of hazards associated with
engines
•Inform you of the risk of injury associated with
those hazards, and
•Tell you how to avoid or reduce the risk of injury.
275749
•Read entire Operating & Maintenance Instructions
AND the instructions for the equipment this engine
powers.*
•Failure to follow instructions could result in serious
injury or death.
*Briggs & Stratton does not necessarily know what equipment this en-
gine will power. For that reason, you should carefully read and under-
stand the operating instructions for the equipment on which your engine
is placed.
The 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.
DANGER indicates 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.
WARNING
The engine exhaust from this
product contains chemicals known
to the State of California to cause
cancer, birth defects, or other
reproductive harm.
HAZARD SYMBOLS AND MEANINGS
Explosion
Toxic Fumes
Moving Parts Shock
Hot Surface
Kickback
Fire
THE INTERNATIONAL SYMBOLS USED
ON THE ENGINE OR
IN THIS MANUAL INCLUDE:
On Off
Fuel Shutoff
Read Owner’s
Manual
Stop Fuel
Choke
Safety Alert
Oil
Hazardous
Chemical
DANGER
•FreshStart fuel cap is designed to hold a cartridge which contains fuel stabilizer.
•IF SWALLOWED, call physician immediately. Do not induce vomiting. If inhaled,
remove to fresh air. In case of eye or skin contact, flush with water for 15 minutes.
•Store unopened cartridges in a cool, dry, well-ventilated area. Keep open cartridge
in fuel cap, and fuel cap closed on fuel tank when not in use.
Contents are HARMFUL OR FATAL IF SWALLOWED. Avoid contact to
eyes, skin, or clothing. Do not take internally. Avoid breathing the mist or
vapor. Overexposure to eyes or skin can cause irritation. Keep stabilizer
out of the reach of children.
Fuel stabilizer is a hazardous chemical. **
Your engine may be
equipped with a
FreshStartEfuel cap.
** Fuel stabilizer contains: 2,6-di-tert-butylphenol (128-39-2) and aliphatic petroleum distillate (64742-47-8).

4
SAFETY
Gasoline and its vapors are extremely
flammable and explosive.
Fire or explosion can cause severe burns
or death.
WARNING
WHEN ADDING FUEL
•Turn engine OFF and let engine cool at least 2
minutes before removing gas cap.
•Fill fuel tank outdoors or in well-ventilated area.
•Do not overfill fuel tank. Fill tank to approximately
1-1/2 inches below top of neck to allow for fuel
expansion.
•Keep gasoline away from sparks, open flames,
pilot lights, heat, and other ignition sources.
•Check fuel lines, tank, cap, and fittings frequently
for cracks or leaks. Replace if necessary.
WHEN STARTING ENGINE
•Make sure spark plug, muffler, fuel cap and air
cleaner are in place.
•Do not crank engine with spark plug removed.
•If fuel spills, wait until it evaporates before starting
engine.
•If engine floods, set choke to OPEN/RUN position,
place throttle in FAST and crank until engine starts.
WHEN OPERATING EQUIPMENT
•Do not tip engine or equipment at angle which
causes gasoline to spill.
•Do not choke carburetor to stop engine.
WHEN TRANSPORTING EQUIPMENT
•Transport with fuel tank EMPTY or with fuel shut-off
valve OFF.
WHEN STORING GASOLINE OR EQUIPMENT
WITH FUEL IN TANK
•Store away from furnaces, stoves, water heaters or
other appliances that have pilot light or other
ignition source because they can ignite gasoline
vapors.
Starting engine creates sparking.
Sparking can ignite nearby flammable
gases.
Explosion and fire could result.
WARNING
•If there is natural or LP gas leakage in area, do not
start engine.
•Do not use pressurized starting fluids because
vapors are flammable.
WARNING
Rapid retraction of starter cord (kickback) will
pull hand and arm toward engine faster than
you can let go.
Broken bones, fractures, bruises or sprains
could result.
•When starting engine, pull cord slowly until
resistance is felt, then pull rapidly.
•Remove all external equipment/engine loads
before starting engine.
•Direct coupled equipment components such as,
but not limited to, blades, impellors, pulleys,
sprockets, etc., must be securely attached.
WARNING
Rotating parts can contact or entangle
hands, feet, hair, clothing, or accessories.
Traumatic amputation or severe laceration
can result.
•Operate equipment with guards in place.
•Keep hands and feet away from rotating parts.
•Tie up long hair and remove jewelry.
•Do not wear loose-fitting clothing, dangling
drawstrings or items that could become caught.

5
SAFETY
Engines give off carbon monoxide, an
odorless, colorless, poison gas.
Breathing carbon monoxide can cause
nausea, fainting or death.
WARNING
•Start and run engine outdoors.
•Do not start or run engine in enclosed area, even if
doors or windows are open.
WARNING
Running engines produce heat. Engine
parts, especially muffler, become extremely
hot.
Severe thermal burns can occur on contact.
Combustible debris, such as leaves, grass,
brush, etc. can catch fire.
•Allow muffler, engine cylinder and fins to cool
before touching.
•Remove accumulated combustibles from muffler
area and cylinder area.
•Install and maintain in working order a spark
arrester before using equipment on forest-covered,
grass-covered, brush-covered unimproved land.
The state of California requires this (Section 4442
of the California Public Resources Code). Other
states may have similar laws. Federal laws apply
on federal land.
WARNING
Unintentional sparking can result in fire or
electric shock.
Unintentional start-up can result in en-
tanglement, traumatic amputation, or
laceration.
BEFORE PERFORMING ADJUSTMENTS OR
REPAIRS
•Disconnect spark plug wire and keep it away from
spark plug.
•Disconnect battery at negative terminal (only
engines with electric start).
WHEN TESTING FOR SPARK
•Use approved spark plug tester.
•Do not check for spark with spark plug removed.
ENGINE INFORMATION
TECHNICAL INFORMATION
POWER RATINGS: The power ratings for an individual engine
model are initially developed by starting with SAE (Society of Auto-
motive Engineers) code J1940 (Small Engine Power & Torque
Rating Procedure) (Revision 2002-05). Given both the wide array
of products on which our engines are placed, and the variety of en-
vironmental issues applicable to operating the equipment, it may
be that the engine you have purchased will not develop the rated
horsepower when used in a piece of power equipment (actual “on-
site” power). This difference is due to a variety of factors including,
but not limited to, the following: differences in altitude, tempera-
ture, barometric pressure, humidity, fuel, engine lubrication, maxi-
mum governed engine speed, individual engine to engine variabil-
ity, design of the particular piece of power equipment, the manner
in which the engine is operated, engine run-in to reduce friction
and clean out of combustion chambers, adjustments to the valves
and carburetor, and other factors. The power ratings may also be
adjusted based on comparisons to other similar engines utilized
in similar applications, and will therefore not necessarily match the
values derived using the foregoing codes.

6
ENGINE INFORMATION
1. Primer bulb
2. Air cleaner
3. Fuel fill
4. Finger guard
5. Spark plug wire
6. Carburetor
7. Rope handle
8. Fuel tank
9. Oil fill/Dipstick
10. Side drain plug (if equipped)
11. Muffler/Muffler guard (if equipped)
12. Spark arrester (if equipped)
13. Engine Model Type Code
xxxxx xxxx xx xxxxxxxx
7
4
3
2
1
8
9
11
13
6
5
12
10
GENERAL INFORMATION
This is a single cylinder, overhead valve (OHV), air-cooled engine.
It is a low emissions engine.
In the state of California, OHV Model Series 110000 and
120000 engines are certified by the California Air Resources
Board to meetemissions standardsfor 125 hours. Suchcertifi-
cation does not grant the purchaser, owner or operator of this
engine any additional warranties with respect to the perfor-
mance or operational life of this engine. This engine is war-
ranted solely according to the product and emissions warran-
ties stated elsewhere in this manual.
MODEL SERIES 110000
Bore 2-11/16 in. (68.26 mm). . . . . . . . . . . . . . . . . . . . . . . . .
Stroke 1-51/64 in. (46.00 mm). . . . . . . . . . . . . . . . . . . . . . .
Displacement 10.20 cu. in. (167.4 cc). . . . . . . . . . . . . . . .
MODEL SERIES 120000
Bore 2-11/16 in. (68.26 mm). . . . . . . . . . . . . . . . . . . . . . . . .
Stroke 2-3/64 in. (52.00 mm). . . . . . . . . . . . . . . . . . . . . . . .
Displacement 11.58 cu. in. (189.7 cc). . . . . . . . . . . . . . . . .
TUNE-UP SPECIFICATIONS
Armature air gap 0.006 - 0.014 in. (0.25 - 0.36 mm). . .
Spark plug gap 0.020 in. (0.51 mm). . . . . . . . . . . . . . . . . .
Valve clearance with valve springs installed and piston 1/4 in.
(6 mm) past top dead center (check when engine is cold).
See Repair Manual P/N 272147.
Intake 0.004 - 0.006 in. (0.10 - 0.15 mm). . . . . . . . . . . . .
Exhaust 0.004 - 0.008 in. (0.10 - 0.20 mm). . . . . . . . . . .
Note: For practical operation, the horsepower loading should
not exceed 85% of rated horsepower. Engine power will
decrease 3-1/2% for each 1,000 feet (300 meters) above
sea level and 1% for each 10°F (5.6°C) above 77°F
(25°C). It will operate satisfactorily at an angle up to 15°.

7
OIL
275749
CAUTION: This engine is shipped from Briggs &
Stratton without oil. Check oil level before starting
engine. If you start the engine without oil, the engine
will be damaged beyond repair and will not be covered
under warranty.
OIL CAPACITY
Engine holds approximately 2/3 quart (22 ounces; 0.65 liter).
TYPE OF OIL TO USE
•Use a high quality detergent oil classified “For Service
SF, SG, SH, SJ” or higher, such as Briggs & Stratton
SAE 30, Part Number 100005 (20 oz) 100028 (48 oz), or
Briggs & Stratton Synthetic Oil, Part Number 100074
(32 oz).
•Do not use special additives.
•Choose a viscosity according to the table opposite.
Note: Synthetic oil meeting ILSAC GF-2, API
certification mark and API service symbol
(shown at left) with “SJ/CF ENERGY CON-
SERVING” or higher, is an acceptable oil at all
temperatures. Use of synthetic oil does not
alter required oil change intervals.
°F-20 0 20 40 60 80 100
°C-30 -20 -10 0 10 20 30 40
STARTING TEMPERATURE RANGE ANTICIPATED BEFORE NEXT OIL CHANGE
*
**
32
*CAUTION: Air cooled engines run hotter than
automotive engines. The use of non-synthetic
multi-viscosity oils (5W-30, 10W-30, etc.) in
temperatures above 40°F (4°C) will result in
higher than normal oil consumption. When using a
multi-viscosity oil, check oil level more frequently.
** CAUTION: SAE 30 oil, if used below 40°F (4°C),
will result in hard starting and possible engine bore
damage due to inadequate lubrication.
SAE Viscosity Grades
CHECKING AND ADDING OIL
•Check oil level before starting the engine.
•Check level daily, or after every eight (8) hours.
•Keep oil level at FULL.
CAUTION:
Do not overfill. Overfilling with oil may cause:
•Smoking
•Hard starting
•Spark plug fouling
•Oil saturation of air filter.
[1] Place engine level
and clean around oil
fill area.
[2] Remove dipstick and
wipe clean with cloth.
[3] Replace and tighten dipstick.
Remove and check oil level.
Oil Fill FULL
[4] Oil level should be at FULL line
on dipstick.
[5] If needed, add oil slowly.
[6] Recheck oil level.
Do not over fill.
[7] Replace and tighten dipstick.

8
FUEL
TYPE OF FUEL TO USE
•Use clean, fresh, regular unleaded gasoline with a
minimum of 85 octane. Fresh fuel prevents gum from
forming in the fuel system or on essential carburetor parts.
Purchase fuel in quantity that can be used within 30 days.
•Do not use gasoline which contains Methanol.
•Do not mix oil with gasoline.
•If not equipped with a Fresh Start fuel cap, for engine
protection, use Briggs & Stratton Gasoline Additive
available from your Authorized Briggs & Stratton Dealer
(P/N 5041 or single use pouch).
•This engine is certified to operate on gasoline. Exhaust
Emission Control System: EM (Engine Modifications).
CAUTION: Some fuels, called oxygenated or reformu-
lated gasoline, are gasoline blended with alcohols or
ethers. Excessive amounts of these blends can damage
the fuel system or cause performance problems. If any
undesirable operating symptoms occur, use gasoline
with a lower percentage of alcohol or ether.
ADDING FUEL
[1] Remove cap. Fill tank to approximately 1-1/2
inches below top of neck to allow for fuel
expansion. Be careful not to overfill.
Briggs & Stratton Smart-fillfuel can fills to the
correct level and automatically shuts off, reducing
spills and emissions.
[2] Replace cap before starting.
Fuel Fill
Note: Remove and discard blue plug in fuel fill.
FRESH START FUEL CAP
DANGER
•IF SWALLOWED, call physician immediately.
Cartridgewith Lift N’ PeelEtab.
Cartridge with tab removed.
Contents are HARMFUL OR FATAL IF SWALLOWED.
Avoid contact to eyes, skin, or clothing. Do not take
internally. Avoid breathing the mist or vapor. Overexposure
to eyes or skin can cause irritation. Keep stabilizer out of the
reach of children.
Fuel stabilizer is a hazardous chemical. **
** Fuel stabilizer contains 2,6-di-tert-butylphenol
(128-39-2)and aliphatic petroleum distillate (64742-47-8).
[1] Place cartridge
into fuel cap. [2] Push to “snap” cartridge into
place.
[3] Remove the
tab to expose
membrane.
[4] Reinstall fuel
cap on engine
fuel tank.
[5] Periodically check
the cartridge to
ensure there is still
stabilizer liquid
inside. If it is
empty, remove
cartridge and
replace.

9
STARTING
WARNING
•Do not use pressurized starting fluids.
•Vapors are flammable.
•Smoking,
•Hard starting,
•Spark plug fouling,
•Oil saturation of air filter.
CAUTION
If engine must be tipped to transport equipment, inspect or
remove grass, keep spark plug side of engine up.
Transporting or tipping engine with spark plug down may
cause: KEEP SPARK PLUG UP
STARTING AND OPERATING TIPS
♦Store and fuel equipment in level position.
♦Use fresh fuel. (See Fuel.)
♦Use correct type of oil for expected starting
temperature. (See Oil.)
♦Remove external equipment/engine loads. (See
equipment operating instructions.)
♦Start lawn mower on hard surface or over previously
cut grass.
♦Periodically remove grass buildup under mower
deck. (See Maintenance.)
♦After engine has started, let it warm up several
seconds to several minutes, depending on outside
temperature.
♦For maximum performance and life, operate engine
with choke (if equipped) in RUN and throttle in FAST.
REWIND (MANUAL) STARTER
TO START ENGINE
[1] Check oil level (see p. 7).
[2] Open fuel shut-off valve
(if equipped) 1/4 turn.
[3] Move throttle to FAST (if equipped).
Operate engine with throttle in FAST.
[4] Push stop switch (if equipped) to ON.
[5] Firmly push primer bulb 3 times OR
[6] Rotate choke knob or move choke
control lever to CHOKE position.
Primer Choke
[7] Close safety brake
handle on lawn mowers
and any other equipment
with this feature.
[8] Grasp rope handle. Pull slowly until
resistance is felt, then pull rapidly to
start engine and avoid kickback.
[9] Allow engine to
warm up.
If choke
equipped:
Slowly adjust to-
ward RUN posi-
tion. Wait until
engine runs
smoothly before
each choke
adjustment.
WARNING

10
STARTING AND STOPPING
ELECTRIC (KEY) STARTER (if equipped)
TO START ENGINE
[1] Check oil level (see p. 7).
[2] Open fuel shut-off valve
(if equipped) 1/4 turn.
[3] Move throttle to FAST (if
equipped). Operate en-
gine with throttle in
FAST position.
[4] Firmly push primer bulb 3 times OR
rotate choke knob or move choke control
lever to CHOKE position.
Primer Choke
[5] Close safety brake
handle on lawn mowers
and any other equipment
with this feature.
[6] Insert key and
turn to START.
CAUTION: To prolong starter life, use short
starting cycles (5 seconds maximum, then wait
one minute). Follow equipment manufacturer’s
recommendations for charging battery. [7] Allow engine to warm up.
If choke equipped:
Slowly adjust toward
RUN position. Wait until
engine runs smoothly
before each choke
adjustment.
TO STOP ENGINE
CAUTION: Do not stop engine by moving choke
control to CHOKE. Backfire, fire or engine damage
could occur.
[1] Move throttle (if
equipped) to
SLOW, then re-
lease safety brake
control handle.
[2] Move throttle
(if equipped)
to SLOW,
then to STOP.
OR [3] Push stop switch (if equipped) to
OFF.
[4] Turn key to OFF. Remove key
and store out of reach of
children.
[5] Close fuel
shut-off valve
(if equipped).
OR