MTD YM90 - Manual (Page 19)

19
SECTION 7: MAINTENANCE AND REPAIR INSTRUCTIONS
Air Filter
Inside Muffler
Cover
Figure 38 Figure 37
Figure 40 Figure 39
6. Replace the air filter inside the air filter/muffler cover.
See Figure 37.
NOTE: Operating the unit without the air filter and air
filter/muffler cover assembly, will VOID the warranty.
Reinstalling the Air Filter/Muffler Cover
1. Place the air filter/muffler cover over the back of the
carburetor and muffler. Align the screw holes.
2. Insert the four (4) screws into the holes in the air
filter/muffler cover and tighten. See Figure 36.
Do not over tighten.
Spark Arrestor Maintenance
1. Remove air filter/muffler cover. See Removing the Air
Filter/Muffler Cover.
2. Locate muffler front and the two (2) bolts securing it
to the engine. See Figure 41. Remove the two (2)
bolts using a flatblade screwdriver or 5/16-inch
socket or nut driver. Pull muffler off of the engine.
3. Turn muffler over to the back side and locate the
exhaust gasket. Remove the muffler gasket from the
muffler. See Figure 41.
NOTE: If the exhaust gasket is torn or damaged, replace
it with a new gasket before reassembling muffler.
4. Using a small flatblade screwdriver, carefully pry up the
spark arrestor from the recessed hole. See Figure 42.
Remove the spark arrestor from the muffler.
Muffler - Front Side Muffler - Back Side
Bolts Exhaust
Gasket
Spark
Arrestor
Muffler - Back Side
Spark
Arrestor
Flat blade
Screwdriver
Spark Arrestor
5. Clean the spark arrestor with a wire brush. Replace it
if it is damaged or if it is impossible to clean
thoroughly. See Figure 42.
6. Reinstall the spark arrestor by pressing it into the
recessed hole on the muffler's back side. Make sure
it fits tightly against the muffler and is not raised up.
7. Place the exhaust gasket against muffler's back side.
Align the gasket bolt holes with the bolt holes in the
muffler. While holding exhaust gasket in place, insert
the bolts into the muffler's front side. See Figure 41.
8. Place the muffler (with the exhaust gasket in place
and bolts inserted), against the engine, aligning the
bolt holes. Tighten the bolts to secure the muffler to
the engine. If using a torque wrench torque to:
80-90 in.•lb. (9-10.2 N•m).
WARNING: If the muffler is not tightened
securely, it could fall off causing damage to
the unit and possible serious personal injury.
9. Reinstall the air filter/muffler cover.
Figure 42
Figure 41