Toro Groundsmaster 3500 30807 Service Manual page 184

Disassembly
1. Plug all ports and clean the outside of the valve thor-
oughly.
IMPORTANT: Match−mark spools to their associat-
ed bores before disassembly. Spools must be rein-
stalled to the bore from which they were removed.
2. Remove both spool caps and slide the spool assem-
blies from their bores.
3. Remove O–ring and bushing from each spool as-
sembly.
4. Remove wiper seals and O–rings from the spool
bore ends that are opposite the spool caps.
NOTE: Disassemble spool assemblies only if the re-
taining ring, spacer, spring, or washer need replacing.
5. Remove seat retaining plugs, back−up washers,
O–rings, and check springs from the valve body.
6. Remove check poppets, seats, O–rings, and plung-
ers from the valve body.
7. Remove solid plug, back−up washer, and O–ring
from the opposite end of the plunger.
8. Remove plug and O–ring from the top of the valve
body next to the detent plug.
9. Remove detent plug and O–ring from the valve body.
Remove disc, spring, and detent plunger from the body.
Inspection
1. Inspect spools and spool bores for wear. If wear is
excessive, replace valve with new one.
2. Inspect springs and replace as necessary.
3. Inspect plunger, detent plunger, and check poppet
for wear. Replace as necessary.
4. Inspect seat, spacer, and bushing for wear. Replace
as necessary.
5. Inspect disc and washer. Replace as necessary.
6. Inspect cap and plugs for damaged threads and in-
spect O–ring sealing surfaces. Replace as necessary.
Assembly
IMPORTANT: Do not wipe parts with dry paper tow-
els or rags. Lint may cause damage to the hydraulic
system.
Hydraulic System
Use eye protection such as goggles when using
compressed air.
1. Clean all metal parts with solvent and blow dry with
compressed air.
2. Replace check poppets, O–rings, and back−up
washers with new ones.
3. Install new O–rings into the valve body.
4. Slide bushings and new O–rings over the spools.
5. If a spool was disassembled, install washer, spool
spring, spacer, and retaining ring to the spool.
6. Lubricate spools liberally with clean hydraulic fluid
and install into their proper bore.
7. Install spool caps into valve body. Torque caps from
20 to 25 ft−lb (27 to 34 N−m).
8. Lubricate both plungers liberally with clean hydraulic
fluid and install into their proper bore.
9. Install new O–rings, seats, check poppets, and
check springs into the plunger bores.
10.Install O–rings, back−up washers, and seat retaining
plugs into their plunger bores. Torque both plugs from 30
to 35 ft−lb (41 to 48 N−m).
11. Install new O–ring, back−up washer, and solid plug
into the bore with the grooved plunger. Torque plug from
30 to 35 ft−lb (41 to 48 N−m).
12.Install new O–ring, seat, check poppet, check spring,
new O–ring, back−up washer, and seat retaining plug
into the bore with the plunger. Torque plug from 30 to 35
ft−lb (41 to 48 N−m).
13.Install O–ring and plug into the top of the valve body
next to the detent plug bore. Torque plug from 10 to 12
ft−lb (14 to 16 N−m).
14.Lubricate plunger detent, spring, and disc liberally
with clean hydraulic fluid and install into its valve body
bore.
15.Install O–ring and detent plug into its proper bore.
Torque plug from 4 to 5 ft−lb (5.4 to 6.8 N−m).
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CAUTION
Groundsmaster 3500