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12
SECTION 5: MAKING ADJUSTMENTS
Idle Speed Screw
Figure 13
Engine Specifications
Engine Type … … … … … … …Air-Cooled, 2-Cycle
Displacement
… … … … … … … … … … … 31cc
Idle Speed R.P.M.
… … … … …
3,400-4,400 rpm
Operating R.P.M. … … … … … …
6,600-8,000 rpm
Fuel/Oil Mixture Ratio.
… … … … … … … … 32:1
Unit Weight
(No fuel, with cutting attachment, cutting
attachment shield and D-handle) … 9.5 lbs. (4.31 kg)
Carburetor Adjustments
WARNING: If any adjustments are made
to the engine while the engine is running
(e.g. carburetor), keep clear of all moving
parts. Be careful of heated surfaces and
muffler.
The idle speed adjuster of the engine is adjustable
through the air filter/muffler cover. See Figure 13.
NOTE:
Careless adjustments can seriously damage
your unit. An authorized service dealer should make
carburetor adjustments.
Check Fuel Mixture
Old and/or improperly mixed fuel is usually the reason
for the unit not running properly. Drain and refill the
tank with fresh, properly mixed fuel prior to making
any adjustments. Refer to OPERATING YOUR TRIM-
MER in Section 4.
Clean Air Filter
The condition of the air filter is important to the
operation of the unit. A dirty air filter will restrict air
flow and change the air/fuel mixture. This is often
mistaken for an out of adjustment carburetor. Check
the condition of the air filter before adjusting the idle
speed adjuster. Refer to MAINTAINING YOUR
TRIMMER in Section 6.
Adjusting Idle Speed
WARNING: This unit will need to be
running during idle speed adjustment.
Wear protective clothing and observe all
safety instructions to prevent serious
personal injury.
If after checking the fuel mixture and cleaning the
air filter the engine still will not idle, adjust the idle
speed screw as follows.
1.
Start the engine and let it run about 2-3 minutes
at a high idle to warm up. Refer to OPERATING
YOUR TRIMMER in Section 4.
2.
Release the throttle control and let the engine
idle. If the engine stops, insert a small phillips or
flat blade screwdriver into the hole in the air fil-
ter/muffler cover. Turn the idle speed screw in,
clockwise, 1/8 of a turn at a time (as needed) until
the engine idles smoothly. See Figure 13.
3.
If the unit appears to be idling too fast, turn the
idle speed adjuster counterclockwise 1/8 of a turn
at a time (as needed), to reduce idle speed.
NOTE:
If a tachometer is available, set idle speed to
RPM specifications.
Checking the fuel mixture, cleaning the air filter, and
adjusting the idle speed screw should solve most
engine problems.
If not and:
•
The engine will not idle,
•
The engine hesitates or stalls on acceleration,
•
There is a loss of engine power,
have the carburetor adjusted by an authorized service
dealer.
WARNING:
When the unit is turned off
make sure the cutting attachment has
stopped before the unit is set down to
prevent serious personal injury.