22
High Altitude Engine Operation:
Please have an authorized service center modify this engine if it is to be run above 2000 feet. Failure to do so may
result in poor engine performance, spark plug fouling, hard starting, and increased emissions. Carburetor modi-
cation by an authorized service center will improve performance and allow that this engine meet the EPA (Envi-
ronmental Protection Agency) and California ARB (Air Resources Board) emission standards. An engine modied
for high altitudes can not be run at 2000 feet or lower. In doing so, the engine will overheat and cause serious
engine damage. Please have an authorized service center restore high altitude modied engines to the original fac-
tory specication before operating below 2000 feet.
Maintenance
Emissions Maintenance Schedule
Maintenance, replacement, or repair of the emission control device and systems may be performed by any non-
road engine repair establishment or individual.
Emission Part
Inspect
before
each use
Clean every
5 hours
Replace every
25 hours
or yearly
Clean every
25 hours
or yearly
X
X X
X
X
X
Fuel Tank Assembly (Includes Fuel
Lines, Fuel Cap, and Fuel Filter)
Air Filter
Spark Arrester
Spark Plug
Mufer
Replace
every
125 hours
Note: Only use the knob to tighten the bolt. The use of
other tools may allow overtightening of the bolt, which
could damage the string head.
If removed, replace the spring into the string head and
push down to seat.
Reinstall the spool. For the 51954, the spool should be
placed so “This side out for curved shaft” is visible. For
the 51974, the spool should be placed so “This side out
for straight shaft” is visible.
Replace the knob in the spool.
Replace the string head cover, aligning latches with
openings in the string head. Press cover and string head
together until both latches snap into openings securely.
Install line as described in the operation section of this
manual.
Figure 21
Hex-Shaped
Opening
Knob
Hex Bolt
To Next Page
Loading...
Need help?
General
