MTD Yard Machines LT31S, Operator'S Manual

Page: 14 / 20

14
MAINTENANCE AND REPAIR INSTRUCTIONS
CARBURETOR ADJUSTMENT
The idle speed of the engine is adjustable through the air
filter/muffler cover (Fig. 27).
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 improper unit performance. Drain and refill the tank
with fresh, properly-mixed fuel prior to making any
adjustments. Refer to Oil and Fuel Information.
SPARK ARRESTOR MAINTENANCE
NOTE: The exhaust can only flow in one direction: AWAY
from the engine. Pay close attention when
disassembling the muffler so you can put it back
together correctly. Failure to do so will damage
the unit and may cause serious personal injury.
1. Remove air filter/muffler cover. Refer to Removing
the Air Filter/Muffler Cover.
2. Locate the muffler, but do not remove it. Find the two
(2) screws on the bottom of the muffler (Fig. 26).
These two screws hold the Spark Arrestor Hood
Assembly and the spark arrestor screen to the
bottom of the muffler. Remove the two (2) screws
using either a torx #20 or flat blade screwdriver.
3. Using a small flat blade screwdriver, carefully pry up
the spark arrestor screen from the recessed hole,
taking care to notice that the “raised” part of the
spark arrestor screen is inside the recessed hole.
Remove the spark arrestor screen from the muffler.
4. Clean the spark arrestor screen with a wire brush.
Replace it if it is damaged, or if you are unable to
clean it thoroughly.
5. Reinstall the spark arrestor screen by putting the
“raised” portion of the screen inside the recessed
hole of the muffler. Make sure that the spark arrestor
screen fits flat against the muffler.
6. Place the spark arrestor plate on top of the spark
arrestor with the “raised” side up and the opening
facing towards the engine (Fig. 26).
7. Place the spark arrestor hood on top of the spark
arrestor plate with the “raised” side up and the
opening facing AWAY from the engine (Fig. 26). Verify
that the exhaust will be directed AWAY from the
engine.
8. Replace the two screws you removed in Step 2 and
tighten them securely.
9. Reinstall the air filter/muffler cover.
If the exhaust
deflector assembly is
not tightened securely, it could fall off causing
damage to the unit and possible serious
personal injury.
WARNING:
Spark Arrestor
Screen
Spark Arrestor
Plate
Spark Arrestor
Hood
Screws
Muffler
Recessed Hole
Engine
Spark Arrestor Hood
Assembly Includes:
Spark Arrestor Plate
Spark Arrestor Hood
and Screws
Opening
Fig. 26