High Altitude Operation; Oxygenated Fuels; Specifications; Tuneup Specifications - Honda GS160 Owner's Manual

Carburetor Modifications for High Altitude Operation
At high altitude, the standard carburetor air-fuel mixture will be too
rich. Performance will decrease, and fuel consumption will increase. A
very rich mixture will also foul the spark plug and cause hard starting.
Operation at an altitude that differs from that at which this engine was
certified, for extended periods of time, may increase emissions.
High altitude performance can be improved by specific modifications
to the carburetor. If you always operate your trimmer at altitudes
above 5,000 feet (1,500 meters), have your servicing dealer perform
this carburetor modification. This engine, when operated at high
altitude with the carburetor modifications for high altitude use, will
meet each emission standard throughout its useful life.
Even with carburetor modification, engine horsepower will decrease
about 3.5% for each 1,000-foot (300-meter) increase in altitude. The
effect of altitude on horsepower will be greater than this if no
carburetor modification is made.
NOTICE
When the carburetor has been modified for high altitude operation,
the air-fuel mixture will be too lean for low altitude use. Operation at
altitudes below 5,000 feet (1,500 meters) with a modified carburetor
may cause the engine to overheat and result in serious engine
damage. For use at low altitudes, have your servicing dealer return
the carburetor to original factory specifications.

Oxygenated Fuels

Some conventional gasolines are being blended with alcohol or an
ether compound. These gasolines are collectively referred to as
oxygenated fuels. To meet clean air standards, some areas of the
United States and Canada use oxygenated fuels to help reduce
emissions.
If you use oxygenated fuel, be sure it is unleaded and meets the
minimum octane rating requirements.
Before using an oxygenated fuel, try to confirm the fuel's contents.
Some states/provinces require this information to be posted on the
pump.
The following are the EPA approved percentages of oxygenates:
ETHANOL — (ethyl or grain alcohol) 10% by volume
You may use gasoline containing up to 10% ethanol
by volume. Gasoline containing ethanol may be
marketed under the name Gasohol.
MTBE — (methyl tertiary butyl ether) 15% by volume
You may use gasoline containing up to 15% MTBE
by volume.
METHANOL — (methyl or wood alcohol) 5% by volume
You may use gasoline containing up to 5%
methanol by volume as long as it also contains
cosolvents and corrosion inhibitors to protect the
fuel system. Gasoline containing more than 5%
methanol by volume may cause starting and/or
performance problems. It may also damage metal,
rubber, and plastic parts of your fuel system.
If you notice any undesirable operating symptoms, try another service
station or switch to another brand of gasoline.
Fuel system damage or performance problems resulting from the use
of an oxygenated fuel containing more than the percentages of
oxygenates mentioned above are not covered under the Engine
warranty.
E
Specifications – GS160
Length x Width x Height
Dry weight
Engine type
Displacement
[Bore x Stroke]
Max. output
Max. torque
Fuel tank capacity
Fuel consumption
Cooling system
Ignition system
PTO shaft rotation
Specifications – GS190
Length x Width x Height
Dry weight
Engine type
Displacement
[Bore x Stroke]
Max. output
Max. torque
Fuel tank capacity
Fuel consumption
Cooling system
Ignition system
PTO shaft rotation

Tuneup Specifications

ITEM
Valve clearance (cold) IN: 0.15 ± 0.04 mm
EX: 0.20 ± 0.04 mm
Other specifications

Quick Reference Information

Fuel Type
Capacity
Engine oil Type
Capacity
Carburetor Idle speed
Spark plug Type
Gap
Maintenance Before each use
First 5 hours
Subsequent
337 x 369 x 331 mm (13.3 x 14.5 x 13.0 in)
13.6 kg (30 lb)
4-stroke, overhead cam, single cylinder
3
160 cm (9.8 cu-in)
[64 x 50 mm(2.5 x 2.0 in)]
4.6 PS (4.6 bhp, 3.4 kW ) at 3,600 rpm
0.96 kg/m(6.9 ft-lb, 9.4 N•m) at 2,500 rpm
1.8 
1.5 l /h at 3,600 rpm
Forced air
Transistorized magneto
Counterclockwise
345 x 369 x 331 mm (13.6 x 14.5 x 13.0 in)(
13.8 kg (30 lb)
4-stroke, overhead cam, single cylinder
3
187 cm (11.4 cu-in)
[69 x 50 mm (2.7 x 2.0 in)]
5.3 PS (3.9 kW, 5.2 bhp) at 3,600 rpm
1.14 kg/m (11.2 N•m, 8.3 ft-lb) at 2,500 rpm
1.8 
1.6 l /h at 3,600 rpm
Forced air
Transistorized magneto
Counterclockwise
SPECIFICATION MAINTENANCE
See your authorized
Honda dealer
No other adjustments needed.
Unleaded gasoline with a pump octane
rating of 86 or higher (page 5).
1.8  (0.53 US gal)
SAE 10W-30, API SH or SJ, for general use.
Refer to page 5.
0.58  (0.61 US qt)
1,400 ± 150 rpm
BPR6ES (NGK)
0.7 – 0.8 mm (0.028 – 0.031 in)
Refer to page 6.
Check engine oil level. Refer to page 5.
Check air filter. Refer to page 6.
Change engine oil. Refer to page 6.
Refer to the maintenance schedule on
page 5.
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