Ryobi 768r - Manual (Page 19)

MAINTENANCE AND REPAIR INSTRUCTIONS
19
6. Replace the air filter in the air filter/muffler cover
(Fig. 29).
NOTE: Operating the unit without the air filter and
air filter/muffler cover assembly, will VOID the
warranty.
Reinstalling the Airfilter/Muffler Cover
1. Place the air filter/muffler cover over the back of the
carburator and muffler.
NOTE: The choke lever must be in the PARTIAL choke
position (B) (Fig. 28, Pg. 18) to install the air
filter/muffler cover.
2. Insert the four (4) screws into the holes in the air
filter/muffler cover (Fig. 28, Pg. 18) and tighten. Use
a flat blade or # T20 Torx bit screwdriver. Do not
over tighten. Do not force.
CARBURETOR ADJUSTMENT
The idle speed of the engine is adjustable though the Air
filter/muffler cover (Fig 33).
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 Oil and Fuel Information, Pg. 12.
Clean Air Filter
The condition of the air filter is important to the opera-
tion 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 screw. Refer to
Air Filter Maintenance Pg. 18.
5. Squeeze the filter to spread and remove excess oil
(Fig. 32).
Adjust Idle Speed Screw
WARNING: The cutting attachment may be
spinning 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 fil-
ter the engine still will not idle, adjust the idle speed
screw as follows.
1. Start the engine and let it run at a high idle for a
minute to warm up.
2. Release the throttle trigger and let the engine idle. If
the engine stops, insert a small phillips or flat blade
screwdriver into the hole in the air filter/muffler cover
(Fig. 33). Turn the idle speed screw in, clockwise, 1/8
of a turn at a time (as needed) until the engine idles
smoothly.
NOTE: The cutting attachment should not rotate when
the engine idles.
3. If the cutting attachment rotates when the engine
idles, turn the idle speed screw counterclockwise 1/8
of a turn at a time (as needed), to reduce idle speed.
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.
Idle Speed Screw
Fig. 32
Fig. 33