Craftsman 917.271650 Owner's Manual page 26

ENGINE
Maintenance, repair, or replacement of the
emission control devices and systems, which
are being done at the customers expense,
may be performed by any non-road engine
repair establishment or individual Warranty
repairs must be performed by an authorized
engine manufacturer's service outlet.
TO ADJUST THRO'I-rLE CONTROL
CABLE
The throttle control has been preset at the
factory and adjustment should not be
necessary. Check adjustment as described
below before loosening cable. If adjustment
is necessary, proceed as follows:
1. With engine not running, move throttle
control lever from slow to choke posiUon.
Slowly move lever from choke to fast
position.
2. Check that holes "A" in govemor control
lever and hole in govemor plate line-up.
If holes "A" are not aligned, loosen clamp
screw and move throttle cable until holes
are aligned. Tighten clamp screw
securely.
Governor Governor
Lever Plate
Holes "A"" Throttle
Screw Cable
TO ADJUST CARBURETOR
NOTE: The carburetor on this engine is low
emission. It is equipped with an idle fuel
adjusting needle with a limiter cap, which
allows some adjustment w_in the limits
allowed by the cap. Do not attempt to remove
the limiter cap. The limiter cap cannot be
removed without breaking the adjusting
needle.
The carburetor has been preset at the factory
and adjustment should not be necessary.
However, minor adjustment may be required
to compensate for differences in fuel,
temperature, altitude or load. If the carburetor
does need adjustment, proceed as follows:
In general, turning idle mixture valve in
(clockwise) decreases the supply of fuel to
the engine giving a leaner fueVair mixture.
Tuming the idle mixture valve out (counter-
clockwise) increases the supply of fuel to the
engine giving a richer fuel/air mixture.
IMPORTANT: Damage to the needle valve
and the seat in carburetor may resultif screw
istumed in too tight.
PRELIMINARY SETI'ING -
1. Air cleaner assembly must be assembled
to the carburetor when making carburetor
adjustments.
2. Be sure the throttle control cable is
adjusted properly (see above).
FINAL SETI'ING -
1. Start engine and allow to warm for five
minutes. Make final adjustments with
engine running and shift/motion control
lever in neutral (N) position.
2. Move throttle control lever to slow
position. With finger, rotate and hold
throttle lever against idle speed screw.
Tum idle speed screw to attain 1750
RPM.
3. While still holding throttle lever against
idle speed screw, rum idle mixture valve
full travel clockwise then counterclock-
wise until engine runs rough. Turn valve
to a point midway between those two
positions. Release throttle lever.
ACCELERATION TEST -
4. Move throttle control lever from slow to
fast position. If engine hesitates or dies,
turn idle mixture valve out (counterclock-
wise) 1/8tum. Repeattest and continue
to adjust, if necessary, until engine
accelerates smoothly.
High speed stop is factory adjusted. Do riot
adjust or damage may result.
IMPORTANT: Never tamper with the engine
govemor, which is factory set for proper
engine speed. Overspeeding the engine
above the factory high speed setting can be
dangerous. If you think the engine-governed
high speed needs adju_ng, contact a
Sears or other qualified service center,
which has proper equipment and experience
to make any necessary adjustments.
Idle Speed Throttle
Screw_Lever
Idle Mixture Valve _
With Limiter
26