Service Manual

Transmission Acceleration Valves (Fig. 17)
1 . Place a drain pan below the acceleration valves.
2. Remove both acceleration valve plugs and O-rings
from the sides of the center section. Some oil may flow
into the drain pan.
3. Slide the acceleration valve and spring out of the
center section. Also slide the other acceleration valve
out of the opposite side of the center section.
NOTE: There are two acceleration valves in the center
s
ection, but only one spring.
4. Remove the O-rings from the plugs.
5. Inspect the plugs, valves and center section for
damage or stripped threads. Replace any damaged
part.
6. Inspect the bore of the acceleration valve for damage
and f
oreign material. If the valve is damaged, replace it;
however, clean the valve with cleaning fluid and use it
again if foreign material is in its bore.
7. Check the spring for damage and correct specifica-
t
ions. Replace the spring if its condition is doubtful.
Spring specifications are listed in the table below.
Acceleration Valve Spring Specifications
Free Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.25 in.
Number of Coils . . . . . . . . . . . . . . . . . . . . . . . . . . 23-1/2
Outside Diameter . . . . . . . . . . . . . . . . . . 0.297-0.303 in.
Pounds per Inch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
8. To install acceleration valves, place a new O-ring onto
both acceleration valve plugs.
9. Slide one acceleration valve into the center section,
then install plug. Then, slide the spring and remaining
acceleration valve into the opposite side of the center
section. Install the remaining plug to retain the parts in
place.
10. Since some oil has drained out of transmission when
t
he acceleration valves were removed, check the oil
level in the axle housing. Start the engine and let it run
for about one or two minutes. Then turn the engine off
and check the oil level in the axle housing again. Also
inspect the acceleration valve areas for oil leaks.
Figure 17
Repairs Page 5 - 28 Groundsmaster
®
300 Series