MTD YM26CS EN - Manual (Page 21)

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 37).
NOTE: Careless adjustments can seriously damage your
unit. An authorized service dealer should make
carburetor adjustments.
Check Fuel
Old fuel is usually the main reason for the unit not
running properly. Drain and refill the tank with clean,
fresh unleaded fuel prior to doing any adjustments. Refer
to the Oil and Fuel Information section.
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 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 Adjustment Screw
Fig. 37
21
SECTION 7: MAINTENANCE AND REPAIR INSTRUCTIONS
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 screw. Refer to
Air Filter Maintenance in the Maintenance and Repair
Instructions section.
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 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.
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 engine cover
(Fig. 37). 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.
Fig. 36
Back Plate Slot
Slots
Choke Lever
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. 36).
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. 36).
9. Replace the fuel cap, if removed.
Back Plate
Fig. 35
5. Squeeze the filter to spread and remove excess oil
(Fig. 36).
6. Replace the filter (Fig. 35).
NOTE: If the unit is operated without the air filter, you
will VOID the warranty.