Service Manual
GOVERNOR
OPERATION
(Refer to Figure 2-1 3.) As load on the engine in-
creases the enginespeed will start to
decrease. As
the engine slows down the centrifugal force of the
flyweights (1) will decrease. The governor return
spring (4) will cause the governor collar (2) to move
in direction (A).
The
governorarm (3) will also move
in direction (A) causing the throttle to
open
until the
centrifugal force
of
the flyweights are in balance
with the governor return spring. As the load on the
engine decreases the engine will speed up caus-
ing the flyweights to move out forcing the governor
collar in direction (B).
The
collar will act against the
governor arm moving it in direction (B) and also
moving the throttle in direction
(B).
The engine
speed will drop until once again the flyweight and
return spring are in balance (Figure 2-1 3).
1
Figure 2-1
3
Models 47PD3,47PE4 and 47PF5 are equipped
with variable throttles. The linkage is described in
(Figure 2-1 4).
A
mounting boss was added to the
casting of the engine to accommodate the throttle
linkage assembly. The boss does not exist on
model 47PZ2 engines therefore thevariable throt-
tle linkage will not retrofit. Model 47PF5 engines
will include a weld stud on the governor linkage for
ease of reassembly (See Figure 2-1
5).
Governor
Arm
Governor
Spring
Figure 2-1 4
Figure 2-1
5
FUEL
TANK
!
CAUTION:
The gasoline in
the fuel tank is explosive.
Always drain or
fill
tank outdoors,
away from fire and flame.
Do
not
smoke when fuel vapors are present.
For the engine and carburetor to function properly
the fuel supply must be clean. Stale, dirty and im-
properly mixed fuel will cause starting and running
difficulties. To assure a clean fuel supply the fuel
tank may be removed and flushed with fresh fuel.
(See Disassembly Instruction.)
A
non-replaceable
sintered bronze fuel filter is inset into the fuel tank
outlet. In some cases, the filter can be cleaned by
back flushing with solvent or by blowing low pres-
sure compressed air through the fitting on the
bottom of the fuel tank. Commercial engines have
a replaceable inline fuel filter located between the
fuel tank
and carburetor. The
replacementfuel filter
is Toro Part Number 56-6360 (Figure 2-1 6). Period-
ically inspect the vent in the fuel tank cap. Remove
any foreign materials which may plug the
vent. The
gasket inside the cap may be removed to permit
further cleaning of the vent area.
Fuel
Cap
(molded into lank).
Fuel
Filter
Inline
Fuel Filter
Part
No.
56-6360
Figure 2-1 6
11-5