Service Manual

GAS POWER SHOVEL
9 - 6 Single Stage Snowthrower Service Manual
PRIMER OPERATION
The primer, used on the Toro Gas Power Shovel is
designed to pump a small amount of fuel from the
carburetor into the carburetor throat. This extra fuel
mixture assists with starting of a cold engine.
The primer is operated by depressing the primer bulb
while ensuring that the vent hole in the bulb is covered.
Pressing the primer bulb forces air against the outside
of the diaphragm in the carburetor. The upward
movement on the diaphragm lifts the inlet needle and
allows fuel into the fuel chamber. The fuel in the fuel
chamber is then forced through the fuel passages and
into the carburetor throat. For temperatures below 0°F
(-18°C) use two or three primes. For temperatures
above 0°F (- 18°C) use one or two primes. In colder
conditions, more primes may be necessary. If the
engine is warm, do not use the primer.
CHOKE OPERATION
The carburetor choke control or shutter meters the
amount of air passing into the engine. When starting
the engine, the carburetor choke should be closed.
The choke shutter allows air to enter the carburetor
only through openings in and around the choke shutter.
When the engine is cranked, a low pressure area is
created in the engine and carburetor. Since only a
limited amount of air can enter the low pressure area
because of the closed choke shutter, a greater amount
of fuel is pushed through the fuel passages to fill the
void. This creates the richer mixture needed for engine
starting and restarting after the engine is warm.
After the engine starts, more air must pass into the
engine. Therefore, after the engine is started, open the
choke shutter to allow more air to pass into the engine.
On the Toro Gas Power Shovel, the choke control knob
should be rotated clockwise to open the choke.
On/Off Switch
The Gas Power Shovel ignition switch allows the
engine to be started with the switch knob in the “ON”
position. Rotating the knob to the “OFF” position will
ground the ignition system and will stop the engine.
TESTING THE SWITCH
The On/Off switch used on the Gas Power Shovel
consists of a set of contact switch terminals and an
actuator switch (Figure 193).
Figure 193 0406-014
To check the switch:
1. Visually inspect the individual switch parts for
damage. To determine if the contact switch
terminals have adequate contact pressure against
the actuator switch, gently pull upward on both of
the switch terminals to ensure that they spring
back into position. If the individual switch parts
are damaged, they should be replaced.
The switch contact terminals are riveted to the
control bracket. The rivets can be removed from
the bracket with a punch and new terminals can
be attached to the bracket with a rivet gun.
2. Disconnect either one or both of the ignition
module wires from the contact switch terminals.
Inspect the wires for damage.
3. Remove the On/Off switch knob from the upper
shroud and insert it into the On/Off switch control.
With the switch knob “arrow” turned
counterclockwise to the 10 o’clock position, the
raised portion of the switch actuator should be
located midway between the two contact switch
terminals.