Toro Groundsmaster 328-D, Service Manual

Page: 133 / 402

Transmission Center Section (Fig. 28)
1 . Separate the center section from the motor and pump
housings; refer to "Separating Transmission Into
Sections".
2. Wrap the pump side of the center section with a clean
rag to protect its face. Set the center section on a clean
work bench so that the motor side faces up. The rag will
protect the pump side of the center section from direct
contact with the top of the work bench.
3. Remove the two slotted directional charge check
plugs from the motor side of the center section. Invert
the center section and allow the two valve springs and
check balls to fall into your cupped hand. Also remove
the two O-rings from the pump side of the center section.
4. If the needle bearings must be serviced, press them
out of the center section.
5. Clean and inspect the following parts:
A. Slotted plugs and O-rings - Check the slotted
plugs for damaged threads and burrs. Also check the
O-ring for tears. It is a good practice to install new
O-rings whenever the slotted plugs are removed.
B. Valve Springs and Check Balls - Check the valve
springs and check balls for damage. Spring
specifications are listed in the table below.
Check Valve Spring Specifications
Free Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.550 in
Number of Coils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Outside Diameter . . . . . . . . . . . . . . . . . 0.217 - 0.219 in.
Pounds Per Inch . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.67
C. Needle Bearings - Check for free rotation and any
noticeable damage.
D. Dowel Pins - Check the dowel pin on the motor
side and the pump side of the center section for wear
and damage.
NOTE: Replace any defective parts. The slotted plugs,
valve springs, and check balls are interchangeable.
6. If the needle bearings were removed, press new
bearings into the center section. Allow 3/32 - 1/8 inch of
the bearing to extend beyond the face of the center
section because the motor valve plate and pump valve
plate pilot on the two bearings.
7. Press the locating pins into the holes in the motor side
and pump side of the center section.
8. Insert the check balls and valve springs into the two
holes in the motor side of the center section. Slide the
O-rings onto the slotted plugs and install the plugs into
the two holes in the motor side of center section. Insert
the two new O-rings into the holes in the pump side of
the center section.
9. Assemble the transmission sections if no other ser-
vice work is required; refer to "Assembling Transmission
Sections".
Figure 28
Groundsmaster
®
300 Series Page 5 - 37 Repairs