Toro 51955 Manuel De L'utilisateur page 22

 Place the upper housing on the drive shaft. Make sure
the string head is fully seated.
 Install the hex bolt into the opening on the drive shaft
and secure using the hex-shaped opening in the knob to
tighten. Turn clockwise for curved shaft and counter-
clockwise for straight shaft to tighten.
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 51955, the spool should be
placed so "This side out for curved shaft" is visible. For
the 51975, 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.
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
Fuel Tank Assembly (Includes Fuel
Lines, Fuel Cap, and Fuel Filter)
Air Filter
Spark Arrester
Spark Plug
Muffler
High Altitude Engine Operation
Please have an authorized service center adjust this engine if it is to be run above 2000 feet. Failure to do so may
result in poor engine performance and increased emissions. An engine adjusted 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 autho-
rized service center restore high altitude modified engines to the original factory specification before operating
below 2000 feet.
22
Inspect
before
Clean every
each use
5 hours
X
X
Hex-Shaped
Opening
Clean every
Replace every
25 hours
25 hours
or yearly
or yearly
X
X
X
Knob
Hex Bolt
Figure 21
Replace
every
125 hours
X
Maintenance