Section 2. Engine Care - Tecumseh HH100 Handbook

FUELS. Use clean, fresh unleaded automotive gasoline
in all Tecumseh four-cycle engines. (Leaded "regular"
gasoline is an acceptable substitute.)
NOTE: Do Not use gasoline containing methanol
(wood alcohol). Gasoline containing a maximum of
10 ethanol or grain alcohol (sometimes called "gasohol")
may be used but requires special care when engine
is unused for extended periods.
See "STORAGE" instructions.
ENGINE OIL, ALL FOUR CYCLE ENGINES:
USE A CLEAN, HIGH QUALITY, DETERGENT OIL.
Be sure original container is marked with engine
service classification "SF - SJ."
DO NOT USE SAE10W40 OIL.
FOR SUMMER (ABOVE 32°F, 0°C) USE SAE 30 OIL
(SAE10W30 is an acceptable substitute.)
FOR WINTER (BELOW 32°F, 0°C) USE SAE 5W20
OR 5W30 OIL.
(SAE10W is an acceptable substitute.)
(BELOW 0°F, -18°C ONLY) Use 0W30 oil or SAE10W
oil diluted with 10% kerosene is acceptable.
NOTE: For severe, prolonged, winter operation of
HH120 model, SAE10W oil is recommended.
OIL CHANGE INTERVALS. Change oil after first two
(2) hours of operation and every 25 hours thereafter,
or more often if operated under dusty or dirty conditions.
OIL CHECK. Check oil every 5 hours or each time
the equipment is used. Position equipment so the
engine is level when checking the oil.
BREAK-IN PROCEDURE. Proper break-in procedure
is important for proper seating of rings, on a new
engine or newly overhauled engine.
Do normal work with the unit, running the engine
under load. Vary the load on the engine frequently
to aid in seating of the rings.
The engine should not be allowed to idle or run at
part throttle for extended periods during break-in.
Work the engine but do not abuse it.
TUNE-UP PROCEDURE. The following is a minor
tune-up procedure. When this procedure is completed,
the engine will operate properly or you may discover
that further repairs may have to be performed.
NOTE: It is recommended to use only factory parts
in a Tecumseh engine. This is especially important
with an air filter, since the use of any other than the
specified part number may result in serious damage
to the engine.
2

SECTION 2. ENGINE CARE

CAUTION: Remove spark plug wire before doing
any service work on engine.
1. Service or replace air cleaner as necessary.
2. Inspect level and condition of oil; drain oil.
3. Remove blower housing, clean all dirt, grass or
4. Remove cylinder head, remove carbon, inspect
5. Remove carburetor, clean and install carburetor
6. Remove flywheel, check for leaks in oil seals,
7. Make sure all remote linkage is properly adjusted
8. Replace fuel and oil.
9. Run engine and adjust carburetor and set R.P.M.
STORAGE:
Gasoline can become unstable in less than 30 days
and form deposits that can impede proper fuel flow
and engine operation. To prevent deposits from forming,
all gasoline must be removed from the fuel tank and
the carburetor. An acceptable alternative to removing
all gasoline is adding a fuel stabilizer to the gasoline.
Fuel stabilizer (such as Tecumseh's Part No. 730245)
is added to the fuel tank or storage container. Always
follow the mix ratio found on the stabilizer container.
Run the engine at least 10 minutes after adding the
stabilizer to allow it to reach the carburetor.
debris from intake screen, head and cylinder cooling
fins and carburetor governor levers and linkage.
valves and cylinder bore. Replace head using
a new head gasket. Torque to specifications.
kit, make adjustment pre-sets where needed.
Make sure fuel tank, fuel filters and fuel lines
are clean. Reinstall carburetor, replacing any worn
or damaged governor springs or linkage. Make
proper governor adjustment.
check flywheel key and reinstall flywheel. Replace
spark plug and check for spark.
for proper operation.
to specifications found on Microfiche or computer
parts lookup.
(IF THE ENGINE IS TO BE UNUSED
FOR 30 DAYS OR MORE)
CAUTION: NEVER STORE THE ENGINE WITH
FUEL IN THE TANK INDOORS , IN ENCLOSED
POORLY VENTILATED AREAS WHERE FUEL
FUMES MAY REACH AN OPEN FLAME, SPARK
OR PILOT LIGHT AS ON A FURNACE, WATER
HEATER, CLOTHES DRYER OR OTHER GAS
APPLIANCE.