Troy-Bilt TB425CS - Manual (Page 18)

18
Fig. 60
Back Plate Slot
Slots
6. Replace the filter (Fig. 60).
NOTE: If the unit is operated without the air filter, you
will VOID the warranty.
7. Reinstall the air filter cover. Position the hooks on
the left side of the air filter cover into the slots at the
left side of the back plate (Fig. 60).
NOTE: It may be necessary to remove the fuel cap to
reinstall the air filter cover.
8. Swing the cover to the right until the tab on the air
filter cover snaps into place in the slot on the back
plate (Fig. 60).
9. Replace the fuel cap if it was removed.
Back Plate
CARBURETOR ADJUSTMENT
The idle speed of the engine is adjustable. An idle
adjustment screw is reached though a hole in the top of
the engine cover (Fig. 61).
NOTE: Careless adjustments can seriously damage your
unit. An authorized service dealer should make
carburetor adjustments.
Check Fuel
Old fuel is usually the reason for improper unit
performance. Drain and refill the tank with fresh fuel prior
to making any adjustments. Refer to Oil and Fuel
Information.
MAINTENANCE AND REPAIR INSTRUCTIONS
Idle Adjustment Screw
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. 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.
Adjust Idle Speed Screw
If, after checking the fuel 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 at a high idle for a minute
to warm up. Refer to Starting/Stopping Instructions.
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. 61). 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, cleaning the air filter, and adjusting
the idle speed should solve most engine problems. If not
and all of the following are true:
• 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.
Fig. 61
The cutting
attachment may spin
during idle speed adjustments. Wear
protective clothing and observe all safety
instructions to prevent serious personal injury.
WARNING:
To prevent serious
personal injury,
make sure the cutting attachment has
stopped rotating before you turn it off and
set it down.
WARNING: