Ryobi 790r Trimmer User Manual


 
18
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 (Fig. 33) and tighten.
Do not over tighten.
SPARK ARRESTOR MAINTENANCE
1. Remove air filter/muffler cover. Refer to Removing
the Air Filter/Muffler Cover.
2. Locate muffler front and the two (2) bolts securing it
to the engine (Fig. 38). 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 (Fig. 38).
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 (Fig. 39).
Remove the spark arrestor from the muffler.
5. Clean the spark arrestor with a wire brush. Replace it
if it is damaged or if it is impossible to clean
thoroughly (Fig. 39).
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 (Fig. 38).
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)
9. Reinstall the air filter/muffler cover.
Fig. 39
Fig. 38
Muffler - Front Side
Muffler - Back Side
Bolts
Exhaust
Gasket
Spark
Arrestor
Muffler - Back Side
Spark
Arrestor
Flatblade
Screwdriver
Spark Arrestor
WARNING:
If the muffler is not tightened
securely, it could fall off causing damage to
the unit and possible serious personal injury
MAINTENANCE AND REPAIR INSTRUCTIONS