Toro VACU-POWER Service Manual page 46

TRANSMISSION
Figure
57
14.
Place the wheel pinion onto the output shaft.
It is
symmetrical and can be put on either way.
15, Install the internally tabbed thrust washer onto
the output shaft making sure that the contours of
the tab follow the contours of the keyway.
16.
Slip the spring onto the end of the output shaft
and secure with the special retaining clip. Again,
make sure that the center tab fits properly into
the keyway to prevent rotation of the clip. See
Figure
58.
Figure
58
17. Slip the wheel, the original number of spacers,
and the wheel cover onto the shoulder bolt and
secure to the pivot arm using the nylon locknut.
18.
Grease with a No. 2 type lithium-based grease.
As a rule, use two pumps to insure that you do
not overgrease. Be sure to grease after every 25
hours of use to insure maximum service life.
Vacu-Power Mower
41
Transmission Operation
Power from the engine is transferred to the wheels by
means of a belt and a three speed transmission. The
belt and transmission are easiest to understand when
broken down into smaller systems.
Input
System: Power is transferred from the engine to
the transmission via a belt. The self-propel pulley at
the engine is keyed to the crankshaft. The
self-propelled pulley on top of the transmission is
supported by a ball bearing and drives a pinion gear
inside the transmission. Tensioning of the belt is
accomplished by rocking the transmission. When the
operator squeezes the control bar toward the handle,
a
cable is tightened which tilts the transmission
backward and tensions the
belt.
When the control bar
is released, gravity rocks the transmission forward to
loosen the belt.
Belt guides at the engine pulley and atop the
transmission insure disengagement by forcing the belt
to loop around the pulleys. See Figure 59.
Figure 59
Speed Reduction System: Speed reduction is
accomplished by two sets of gears--one set on the
intermediate shaft and the other
set
on the output
shaft. The gears on the intermediate shaft are
powdered metal and ride on a hexagonal shaft
supported on each end by
oil
impregnated bushings.
These gears are driven by the pinion at the bottom of
the input shaft. The driven bevel gear turns the shaft
so
that
all three gears on the intermediate shaft have
the same rotational velocity. See Figure 60.
There are also three gears on the output shaft,
however, these three gears rotate freely on the gear
sleeve. The gear sleeve is coupled to the output shaft
Self-Propel System