Stopping, Maintenance and adjustments, Throttle control to check operation – Bolens 139-402A User Manual
Page 9: Carburetor adjustments: see figure 14, To adjust: see figure 13
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3. Slowly release the clutch pedal.
4. To stop, depress the clutch and the brake
pedals.
5.
The blades can be engaged either while
moving or while standing still. Move the lift
and disengagement lever forward slowly until
the blades are running.
STOPPING
Engine—Turn the ignition key to the left to the
OFF position.
Rider—Depress the clutch and brake pedals.
Blades—Pull the lift and disengagement lever all
the way back and lock it.
MAINTENANCE AND
ADJUSTMENTS
THROTTLE CONTROL
To Check Operation:
1. Remove air cleaner.
2.
Move
throttle
control
lever
to
CHOKE
position. The carburetor choke should be
closed.
3. Move throttle control lever to STOP position.
Lever should make good contact with stop
switch.
CARBURETOR ADJUSTMENTS: See figure 14.
Minor carburetor adjustment may be required to
compensate for differences in fuel, temperature,
altitude and load.
Initial Adjustment:
Turn needle valve clockwise to close it. Then
open 2 turns. This initial adjustment will permit
the engine to be started and warmed up before
making final adjustment.
FIGURE 14. CARBURETOR ADJUSTMENT
Final Adjustment:
With engine running at normai operating speed
(approximately
3000
RPM
without
load)
turn
needle valve clockwise until engine starts to lose
speed (lean mixture). Then slowly turn needle
valve counterclockwise past the point of smooth
est operation, until engine just begins to run
unevenly. This mixture will give best performance
under load.
To Adjust: See figure 13.
Place remote control lever on equipment in FAST
(high speed) position.
Lever C on carburetor should be just touching
choke arm at D. To adjust, loosen casing clamp
screw A on blower housing. Move control casing
B forward or backward until correct position is
obtained. Tighten screw A.
Recheck operation of controls after adjustment.
Replace air cleaner.
To check adjustment move engine control from
SLOW to FAST speed. If engine tends to stali or
die out, it usually indicates that the mixture is
slightly lean and it may be necessary to open the
needle valve slightly to provide a richer mixture.
This richer mixture may cause a slight unevenness
in idling.
CHAIN ADJUSTMENT: See figure 15.
After the first five hours of operation the initial
slack should be removed from the chain. The
chain should be tight enough so that it deflects
approximately Va” when it is depressed with the
thumb.
To Adjust:
The adjusting bolt is located under the frame,
above the cutting deck on the right side of
the mower.
Turn the adjusting bolt clockwise with an open
end wrench until the chain reaches the proper
tension.