Toro Groundsmaster 7210 Service Manual page 182

Disassembling the Polar Trac Hydraulic Control Valve (continued)
Inspecting the Polar Trac Hydraulic Control Valve
Assembling the Polar Trac Hydraulic Control Valve
Hydraulic System: Service and Repairs
Match-mark spools to their associated bores before disassembly.
The spools must be installed again to the bore from which they
were removed.
2. Remove the 2 spool caps (item 10 in
assemblies from their bores.
3. Remove the O-ring (item 12 in
assembly.
4. Remove the wiper seals (item 20 in
bore ends that are opposite to the spool caps.
Note: Disassemble the spool assemblies only if the retaining ring (item 13 in
Figure 126), spacer, spool spring, or washer needs replacement.
5. Remove the seat retaining plugs (items 7 and 15 in
washers, O-rings, and check spring from the valve body.
6. Remove the check poppet (item 1 in
plungers from the valve body.
7. Remove the solid plug (item 6 in
from the opposite end of the plunger.
8. Remove the detent plug (item 19 in
body, and remove the disc, spring, and detent plunger from the body.
1. Inspect the spools and spool bores for wear. If wear is excessive, replace the
control valve with new one.
2. Inspect the springs and replace as necessary.
3. Inspect the plunger and detent plunger for wear. Replace as necessary.
4. Inspect the caps and plugs for damaged threads and inspect the O-ring
sealing surfaces. Replace as necessary.
Do not wipe the control valve parts dry with paper towels or a cloth.
They let lint accumulate in the hydraulic system, which will damage
it.
Use eye protection such as goggles when using compressed air.
1. Clean all the metal parts with solvent and blow dry with compressed air.
2. Replace the check poppet (item 1 in
washers with new ones.
3. Install new O-rings (item 12 in
IMPORTANT
Figure
Figure 126) and bushing from each spool
Figure
Figure
Figure 126), back-up washer, and O-ring
Figure
IMPORTANT
CAUTION
Figure
Figure 126) into the valve body.
Page 4–122
126) and slide the spool
126) and O-rings from the spool
Figure 126), back-up
126), seats, O-rings, and
126) and O-ring from the valve
126), O-rings, and back-up
Groundsmaster 7210
16222SL Rev C