Replacing The Spark Plug; Inspecting/Cleaning The Muffler - Ryobi 310r Operator's Manual

MAINTENANCE AND REPAIR INSTRUCTIONS (Continued)
NOTE: If the carburetor adjustments do not help
the unit to run properly, contact your
authorized service dealer.
Fig. 32

REPLACING THE SPARK PLUG

Use a Champion RDJ7Y spark plug (or equivalent). Correct
air gap is .025 in (0.635 mm). Remove plug after every 50
hours of operation and check its condition.
1. Stop the engine and pull the wire off of the spark
plug.
2. Clean around the spark plug and remove it from the
cylinder head.
NOTE: Replace a cracked, fouled or dirty spark
plug. Do not sand blast, scrape or clean
electrodes because the engine could be
damaged by grit entering thecylinder.
3. Set the air gap at .025 in (0.635 mm) using a wire
feeler gauge (Fig. 33). Install a correctly gapped spark
plug into the cylinder head. Torque to 110-120 in•lb
(12.3-13.5 N•m).
.025 in
(0.635 mm)
Fig. 33

INSPECTING/CLEANING THE MUFFLER

The muffler should be removed every 25 hours of opera-
tion to inspect for excessive carbon build-up. Excessive
deposits around the exhaust ports or exhaust holes will
cause poor engine performance.
Use the following procedure to remove, inspect and clean
and reinstall the muffler.
WARNING
Make sure the muffler is cool before inspecting
and cleaning it.
1. Remove the muffler mounting bolts (Fig. 34).
2. Remove the muffler (with heat shield) and gasket.
Discard the old gasket.
Muffler Mounting Bolts
Fig. 34
Exhaust Exit Tube Removal
The exhaust exit tube is removable on blower and
blower/vac mufflers. To remove the exhaust exit tube:
1. Remove the screws securing the exhaust exit tube to
the muffler body (Fig. 35).
2. Remove the exhaust exit tube and gasket.
15