GB
4
Follow the hourly or calendar intervals, whichever occur first. More frequent
service is required when operating in adverse conditions noted below.
First 5 Hours
D
Change oil
Every 5 Hours or Daily
D
Check oil level
D
Clean around muffler
D
Clean around finger guard
Every 25 Hours or Every Season
D
Change oil if operating under heavy load or high ambient temperature
D
Service air cleaner Oil Foam element *
Every 50 Hours or Every Season
D
Change oil
D
Inspect spark arrester, if equipped
Every 100 Hours or Every Season
D
Replace spark plug
D
Clean cooling system*
*
Clean more often under dusty conditions, or when airborne debris is present or after
prolonged operation cutting tall, dry grass.
CHANGING OIL
Fig. 9
Change oil after first 5 hours of operation, then every 50 hours or every season. Change oil
every 25 hours when operating the engine under heavy load or in high temperatures.
Change oil while engine is warm.
Before tipping engine or equipment to drain oil, drain fuel from tank by running
engine until fuel tank is empty.
WARNING
1. Run engine until it runs out of fuel. Otherwise, fuel can leak out, creating a fire/explosion
hazard, when you tip engine in Step 4.
2. With engine OFF but still warm remove dipstick.
3. Top oil drain:
Keep spark plug side up. On bottom oil drain: By removing drain plug
with a ratchet and square extension
, oil can be drained from engine bottom.
Replace drain plug.
Note: Top oil drain is recommended method, however oil can drain from bottom as shown.
4. Place engine level. Add new oil. Oil capacity of engine is approximately 0.61l (20 oz). Fill
to FULL mark on dipstick. DO NOT OVERFILL. Replace dipstick.
5. Reconnect spark plug wire before starting.
CAUTION: Used oil is a hazardous waste product. Dispose of used oil properly.
AIR CLEANER MAINTENANCE
Fig. 10
All engines have an air cleaner cartridge. Check and clean the cartridge after every 25 hours
of use, more often under dusty conditions. Replace the cartridge after every 100 hours of
use or before each season.
1. Loosen screws and lift cover off.
2. Carefully remove air cleaner cartridge
, preventing debris from falling into carburetor
area
or air vent opening
.
3. Do not use water or solvents to clean cartridge. Simply tap gently to release loose dirt from
cartridge. Replace if worn or very dirty.
CAUTION: Do not use pressurized air or solvents to clean cartridge. Pressurized air will
damage cartridge, solvents will dissolve cartridge.
4. Install new or cleaned filter with the bottom cartridge sealing air vent on base. Replace
cover onto base, and tighten screws.
SPARK PLUG MAINTENANCE
Fig. 11
Check the spark plug every 100 hours or every season, whichever occurs first. Replace the
spark plug if upon inspection the electrodes
are burned or worn. Ensure the spark plug is
clean. Check the gap
with a feeler gage
and reset to 0.51mm or 0.020 in. if
necessary.
Note: In some areas, local law requires using a resistor spark plug to suppress ignition signals.
If this engine was originally equipped with resistor spark plug, use same type of spark plug for
replacement.
DO NOT attempt to start engine with spark plug removed. Fuel can ignite and cause a
fire or explosion.
WARNING
CLEANING DEBRIS
Fig. 12
Daily or before every use, clean grass, chaff, or accumulated debris from engine. Keep
linkage, s‐ring and controls clean. Keep area around and behind muffler free of any
combustible debris. Remove spark arrester. Keeping engine clean allows air movement
around engine.
Do not spray engine with water to clean because water could contaminate fuel. Clean with a
brush or compressed air.
Clean cooling system
To prevent overheating and engine damage, we recommend that you have an authorized
Briggs & Stratton Service dealer clean the air cooling system per the maintenance intervals.
STORAGE
Engines stored over 30 days need to be protected or drained of fuel to prevent gum from
forming in fuel system or on essential carburetor parts. For engine protection, use a Fresh
Start fuel cap. Fuel containers for storage use Fuel Stabilizer. Fresh Start fuel cap cartridge
has enough stabilizer to keep fuel fresh up to 6 months.
If stabilizer is not used or if engine is operating on gasoline containing alcohol, e.g. gasohol,
remove all fuel from tank and run engine until it stops from lack of fuel.
1. Change oil.
2. Remove spark plug and pour about 15 ml (1/2 oz) of engine oil into cylinder. Replace
spark plug and crank slowly to distribute oil.
3. Clean chaff and debris from cylinder and cylinder head fins, under finger guard and
behind muffler.
4. When removing the unit from storage, only use fresh gasoline. Perform operation checks,
see maintenance schedule, before starting engine.
SERVICE
See an Authorized Briggs & Stratton Service Dealer. Each one carries a stock of Genuine
Briggs & Stratton Parts and is equipped with special service tools.
Need Assistance? Go to the website or call, 1‐800‐233‐3723, (U.S.A. and Canada) to hear
a menu of pre‐recorded messages offering engine maintenance information.
Air cleaner cartridge
792038
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oil
100005 ‐or‐ 100028
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel stabilizer (4.2 oz., 125 ml bottle)
5041
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Standard spark plug
692051
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spark tester
19368
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spark plug wrench
89838 (5023)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oil pump kit
5056
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
(uses standard electric drill to remove oil from engine quickly)
To purchase, or view other products Briggs & Stratton has available, see an
Authorized Briggs & Stratton Service Dealer. Use our web site at
www.briggsandstratton.com
to find a dealer nearest you, or check the
“Yellow Pages
™
”.
™
Walking fingers logo and “Yellow Pages” are registered
trademarks in various jurisdictions.
Insist on Genuine Briggs & Stratton replacement parts with our logo on the box and/or part.
Non‐original parts may not perform as well and may void your warranty.
TUNE‐UP SPECIFICATIONS
Armature air gap
0.15 - 0.35 mm (0.006 - 0.014 in.)
. . . . . . . . . . . . . . . . . . . . . . . . . . .
Spark plug gap
0.51 mm (0.020 in.)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Model 100000
Bore
64.00 mm (2.52 in.)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stroke
49.99 mm (1.968 in.)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Displacement
161 cc (9.82 cu in.)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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 105 F (5.65 C) above 775 F (255 C). It will operate satisfactorily at an
angle up to 155. Refer to the equipment operator manual for safe allowable operating limits
on slopes.
