Hyster Fortis S40FT User manual

Hyster U005 (H80FT, H90FT, H100FT, H110FT,
H120FT) Forklift Service Repair Manual

MAIN CONTROL VALVE
WITH VARIABLE
DISPLACEMENT PUMP
S4.0FT, 4.5FT, 5.5FT, S5.5FTS (S80, 100,
120FT; S80, 100FTBCS; S120FTS; S120FTPRS)
[J004];
H4.0FT5/FT6; H4.5FTS5, H4.5FT6; H5.0-5.5FT
(H80, 90, 100, 110, H120FT) [U005]
PART NO. 4128559 2000 SRM 1899

SAFETY PRECAUTIONS
MAINTENANCE AND REPAIR
• The Service Manuals are updated on a regular basis, but may not reflect recent design changes to the
product. Updated technical service information may be available from your local authorized Hyster®
dealer. Service Manuals provide general guidelines for maintenance and service and are intended for
use by trained and experienced technicians. Failure to properly maintain equipment or to follow in-
structions contained in the Service Manual could result in damage to the products, personal injury,
property damage or death.
• When lifting parts or assemblies, make sure all slings, chains, or cables are correctly fastened, and
that the load being lifted is balanced. Make sure the crane, cables, and chains have the capacity to
support the weight of the load.
• Do not lift heavy parts by hand, use a lifting mechanism.
• Wear safety glasses.
• DISCONNECT THE BATTERY CONNECTOR before doing any maintenance or repair on electric lift
trucks. Disconnect the battery ground cable on internal combustion lift trucks.
• Always use correct blocks to prevent the unit from rolling or falling. See HOW TO PUT THE LIFT
TRUCK ON BLOCKS in the Operating Manual or the Periodic Maintenance section.
• Keep the unit clean and the working area clean and orderly.
• Use the correct tools for the job.
• Keep the tools clean and in good condition.
•Always use HYSTER APPROVED parts when making repairs. Replacement parts must meet or ex-
ceed the specifications of the original equipment manufacturer.
• Make sure all nuts, bolts, snap rings, and other fastening devices are removed before using force to
remove parts.
• Always fasten a DO NOT OPERATE tag to the controls of the unit when making repairs, or if the unit
needs repairs.
•Be sure to follow the WARNING and CAUTION notes in the instructions.
• Gasoline, Liquid Petroleum Gas (LPG), Compressed Natural Gas (CNG), and Diesel fuel are flamma-
ble. Be sure to follow the necessary safety precautions when handling these fuels and when working
on these fuel systems.
• Batteries generate flammable gas when they are being charged. Keep fire and sparks away from the
area. Make sure the area is well ventilated.
NOTE: The following symbols and words indicate safety information in this
manual:
WARNING
Indicates a hazardous situation which, if not avoided, could result in death
or serious injury.
CAUTION
Indicates a hazardous situation which, if not avoided, could result in minor
or moderate injury and property damage.
On the lift truck, the WARNING symbol and word are on orange back-
ground. The CAUTION symbol and word are on yellow background.

©2015 HYSTER COMPANY
TABLE OF CONTENTS
General .....................................................................................................................................................................1
Main Control Valve Repair .....................................................................................................................................3
Remove ................................................................................................................................................................ 3
Main Control Valve Sections ..............................................................................................................................5
General ............................................................................................................................................................5
Outlet Control Valve Section ......................................................................................................................... 5
Remove ........................................................................................................................................................5
Disassemble ................................................................................................................................................ 5
Clean ........................................................................................................................................................... 7
Inspect .........................................................................................................................................................7
Assemble ..................................................................................................................................................... 7
Install ..........................................................................................................................................................7
Auxiliary Control Valve Section .................................................................................................................... 7
Remove ........................................................................................................................................................7
Disassemble ................................................................................................................................................ 9
Clean ........................................................................................................................................................... 9
Inspect .........................................................................................................................................................9
Assemble ................................................................................................................................................... 10
Install ........................................................................................................................................................10
Tilt Control Valve Section ............................................................................................................................ 10
Remove ......................................................................................................................................................10
Disassemble .............................................................................................................................................. 10
Clean ......................................................................................................................................................... 11
Inspect .......................................................................................................................................................12
Assemble ................................................................................................................................................... 12
Install ........................................................................................................................................................12
Lift/Lower Control Valve Section .................................................................................................................12
Remove ......................................................................................................................................................12
Disassemble .............................................................................................................................................. 12
Clean ......................................................................................................................................................... 13
Inspect .......................................................................................................................................................14
Assemble ................................................................................................................................................... 14
Install ........................................................................................................................................................14
Transition Section .........................................................................................................................................14
Remove ......................................................................................................................................................14
Disassemble .............................................................................................................................................. 14
Clean ......................................................................................................................................................... 14
Inspect .......................................................................................................................................................15
Assemble ................................................................................................................................................... 16
Install ........................................................................................................................................................16
Install .................................................................................................................................................................16
Pressure Relief Valve Check and Adjustment .....................................................................................................20
General .............................................................................................................................................................. 20
Secondary Relief Valve ..................................................................................................................................... 20
Steering Control Unit Repair ............................................................................................................................... 22
Remove .............................................................................................................................................................. 22
Disassemble .......................................................................................................................................................22
Clean ..................................................................................................................................................................26
Inspect ............................................................................................................................................................... 26
Assemble ............................................................................................................................................................26
Table of Contents
i

TABLE OF CONTENTS (Continued)
Install .................................................................................................................................................................27
System Relief Valve .......................................................................................................................................... 28
Disassemble .................................................................................................................................................. 28
Clean ..............................................................................................................................................................28
Inspect ........................................................................................................................................................... 28
Assemble ....................................................................................................................................................... 28
Accumulator Replacement ....................................................................................................................................29
Remove .............................................................................................................................................................. 29
Install .................................................................................................................................................................30
This section is for the following models:
S4.0FT, 4.5FT, 5.5FT, S5.5FTS (S80, 100, 120FT; S80, 100FTBCS; S120FTS;
S120FTPRS) [J004];
H4.0FT5/FT6; H4.5FTS5, H4.5FT6; H5.0-5.5FT (H80, 90, 100, 110, H120FT)
[U005]
Table of Contents
ii

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General
This section contains a description and repair
procedures for a electro-hydraulic main control
valve with variable displacement pump used in the
hydraulic system for this series of lift trucks.
The electro-hydraulic (E-Valve) main control valve
is controlled electronically. It is mounted to the
cowl using three mounting bolts. See Figure 1.
NOTE: MAJOR COMPONENTS NOT SHOWN FOR
CLARITY. VIEW IS FROM THE FRONT.
1. COWL
2. INSERT
3. WASHER
4. MOUNTING CAPSCREW
5. MAIN CONTROL VALVE
6. FRAME
Figure 1. Main Control Valve Mounting
The E-Valve with variable displacement pump
(VDP) is electronically-controlled, closed-center,
single function compensated, and utilizes parallel
hydraulic circuitry. Load sensing is done through
the VDP. Operating multiple functions
simultaneously will result in a non-proportionate
increase in pump flow to functions which receive
the lowest amount of pressurized fluid. The
hydraulic circuitry will incorporate dual pressure
relief logic.
Lift function pressure is regulated by the pump
pressure compensator. The pump compensator will
be set to the maximum system pressure and a
clipper relief valve will be present in the transition
section of the valve and set slightly higher. The
clipper relief valve adjustment is tamper proof. Tilt
and auxiliary functions are on secondary relief
pressure setting. Lift pressure is not affected by
secondary relief operation.
The electronic main control valve with variable
displacement pump assembly is divided into the
following sections (see Figure 2):
• Steering Control Unit (SCU)
• Transition section
• Lift/Lower section
• Tilt section
• Auxiliary section(s)
• Outlet section
2000 SRM 1899 General
1

NOTE: FOUR FUNCTION CONTROL VALVE SHOWN.
1. STEERING CONTROL UNIT (SCU)
2. SCU MOUNTING CAPSCREW
3. CLIPPER RELIEF VALVE WITH TAMPER
PROOF CAP
4. LIFT/LOWER SECTION
5. PROPORTIONAL PRESSURE REDUCING
VALVE (PPRV)
6. TILT SECTION
7. SECONDARY RELIEF VALVE
8. AUXILIARY I SECTION
9. AUXILIARY II SECTION
10. ACCUMULATOR PORT
11. EMERGENCY LOWERING VALVE
12. TRANSITION SECTION
13. LOAD SENSING (LS) PORT
14. EF PORT
Figure 2. Electronic Control Valve With Variable Displacement Pump
General 2000 SRM 1899
2

Main Control Valve Repair
REMOVE
WARNING
Lower carriage completely before working on con-
trol valve or hydraulic system. DO NOT work un-
der a raised carriage. Put mast in a vertical posi-
tion, with no forward or back tilt, and lower car-
riage completely before disconnecting any parts
of hydraulic system. The mast can lower suddenly
and cause injury if the carriage is not lowered.
NOTE: Most of the individual valve components
can be removed and replaced while the control
valve is installed in the truck. Removal of the con-
trol valve for repairs is normally only required to
replace a valve section, or to replace the O-rings be-
tween the sections.
1. Power wash the interior of the operator com-
partment to remove any dirt or debris.
2. Move truck to disassembly area and shut off en-
gine.
WARNING
Cleaning solvents can be flammable and toxic and
cause skin irritation. When cleaning solvents are
used, always follow the solvent manufacturer’s
recommended safety procedures. Wear protective
goggles or a face shield to prevent eye injuries.
WARNING
Be careful when cleaning with steam. Steam can
cause serious burns. Wear protective clothing,
gloves, and eye protection. Never expose your
skin to steam.
NOTE: Take all necessary steps to prevent debris,
dust, or other contaminants from entering the valve
cavities, hydraulic lines, or replacement parts.
3. Remove the floor plate, kick panel, seal plate,
and dashboard. See Frame 0100SRM1891 for
the procedures.
4. Before disconnecting any hydraulic hoses or re-
moving any parts from the control valve, clean
the outside of the valve either by steam clean-
ing or with cleaning solvent.
5. To remove the accelerator pedal or MONO-
TROL® pedal assembly, disconnect the cowl
wiring harness from the pedal assembly wiring
harness and remove three mounting capscrews.
See Figure 3.
NOTE: To aid in installation, tag all connectors
prior to disconnecting from the solenoids.
6. Disconnect the cowl wiring harness from the
top auxiliary function Proportional Pressure
Reducing Valve (PPRV) solenoids. See Figure 4.
NOTE: ACCELERATOR PEDAL NOT SHOWN,
HOWEVER, REMOVAL IS THE SAME.
1. MOUNTING CAPSCREW
2. MONOTROL PEDAL ASSEMBLY
3. PEDAL ASSEMBLY WIRING HARNESS
Figure 3. MONOTROL Pedal Removal
2000 SRM 1899 Main Control Valve Repair
3

CAUTION
To prevent any foreign matter from getting into ei-
ther the hydraulic hoses or the hydraulic control
valve sections, all openings must have plugs or
covers installed immediately after hoses are dis-
connected from the control valve. This also ap-
plies if any other items are removed from the con-
trol valve.
NOTE: To aid in correctly connecting hydraulic ho-
ses during installation, tag each hose prior to dis-
connecting from the control valve.
7. Disconnect hydraulic hoses from the control
valve. See Figure 4. Install plugs or caps on all
open hose ends and control valve ports to pre-
vent contamination.
8. Remove the two SCU mounting capscrews and
move the SCU approximately 1.3 cm (0.5 in.) to
the left. Lower the SCU until the steering shaft
is disengaged. Remove the SCU from the lift
truck. See Figure 4.
9. Remove and discard three O-rings located be-
tween the transition section and the SCU.
1. STEERING SYSTEM HOSES
2. HYDRAULIC INLET HOSE
3. STEERING CONTROL UNIT (SCU)
4. STEERING SHAFT
5. SCU MOUNTING CAPSCREWS
6. LOAD SENSE LINE
7. LIFT/LOWER HOSE
8. TILT HOSE
9. AUXILIARY I HOSE
10. AUXILIARY II HOSE
11. ACCUMULATOR
12. RETURN HOSE
13. AUXILIARY FUNCTION PROPORTIONAL
PRESSURE REDUCING VALVE HARNESS
(PPRV)
14. VEHICLE SYSTEMS MANAGER
Figure 4. Hydraulic Hose Removal
Main Control Valve Repair 2000 SRM 1899
4

WARNING
The main control valve weighs approximately
30.5 kg (67 lb). Use a lifting device capable of lift-
ing the main control valve to avoid the possibility
of injury to personnel.
10. Support the main control valve with a lifting
device. Remove three mounting capscrews,
washers, and inserts from the main control
valve. See Figure 5.
NOTE: To aid in installation, tag all connectors
prior to disconnecting from the solenoids.
11. Raise the main control valve approximately
25.4 cm (10 in.) to gain access to the lower tilt
and auxiliary function Proportional Pressure
Reducing Valve (PPRV) solenoids. Disconnect
the cowl harness from the lower tilt and auxili-
ary function (PPRV) solenoids.
1. COWL
2. INSERT
3. WASHER
4. MOUNTING CAPSCREW
5. MAIN CONTROL VALVE
6. FRAME
Figure 5. Main Control Valve Removal
12. Remove the main control valve from cowl.
MAIN CONTROL VALVE SECTIONS
General
CAUTION
While working on an electro-hydraulic main con-
trol valve section, place a cover over the remain-
ing sections of the control valve to prevent the
possibility of contaminants getting into the con-
trol valve openings which could cause damage to
the control valve.
CAUTION
If O-rings are to be replaced between two sections
that have a hydraulic oil leak, replace all O-rings
between all sections. This eliminates the possibil-
ity of a subsequent oil leak or possible damage to
another O-ring.
Disassemble the electro-hydraulic main control
valve only as necessary for repairs. Most repairs to
the control valve will be for the replacement of O-
rings to stop leaks between sections.
Outlet Control Valve Section
Remove
1. Remove four nuts from the control valve tie
rods. See Figure 6.
2. Remove the outlet control valve section from
the four tie rods and discard 10 O-rings (item
13 in Figure 7) from the auxiliary control valve
section.
Disassemble
1. If the secondary relief valve has been leaking,
remove it from the outlet control valve section.
See Step 2 through Step 7. See Figure 6.
2. Remove the plug from the adjusting nut. Re-
move and discard the O-ring from the plug. Re-
move and discard the backup rings and O-ring
from the adjusting nut. See Figure 6.
2000 SRM 1899 Main Control Valve Repair
5

3. While holding the adjustment nut, loosen the
jam nut.
NOTE: While performing Step 4, count and note
the number of turns used to remove the adjusting
nut.
4. Remove the adjusting nut and jam nut assem-
bly from the secondary relief valve plug and
discard the O-ring on the adjusting nut.
5. Remove the spring, washer, and poppet from
the secondary relief valve plug.
6. Remove secondary relief valve plug from outlet
control valve section.
7. Remove and discard the backup ring from the
secondary relief valve plug.
1. OUTLET SECTION
2. ACCUMULATOR PORT
3. BACKUP RING
4. SECONDARY RELIEF VALVE PLUG
5. POPPET
6. WASHER
7. SPRING
8. O-RING
9. JAM NUT
10. ADJUSTING NUT
11. PLUG
12. TIE ROD AND NUT (13 mm (½ in.))
13. TIE ROD AND NUT (15 mm (9/16 in.))
Figure 6. Outlet Control Valve Section
Main Control Valve Repair 2000 SRM 1899
6

Clean
WARNING
Cleaning solvents can be flammable and toxic and
can cause skin irritation. When using cleaning
solvents, always follow the solvent manufactur-
er's recommended safety procedures.
WARNING
Compressed air can move particles so they cause
injury to the user or to other personnel. Make sure
the path of the compressed air is away from all
personnel. Wear protective goggles or a face
shield to prevent injury to the eyes.
1. If all components of the outlet control valve sec-
tion have been removed, clean the outlet control
valve section using cleaning solvent and dry us-
ing compressed air.
2. If all components have not been removed, clean
the outlet control valve section using a lint-free
cloth.
Inspect
Inspect the outlet control valve section mating sur-
faces and the bore of the secondary relief valve, if
removed, for damage. If either the mating surface
or the secondary relief valve bore are damaged, re-
place the outlet control valve section.
If disassembled, inspect the components of the sec-
ondary relief valve. If any components other than
O-rings, backup rings, and the spring are damaged,
replace the secondary relief valve.
NOTE: If the outlet control valve section is not to
be reassembled immediately, coat surfaces with
clean hydraulic oil to prevent the possibility of rust.
Cover the outlet control valve section with a clean,
dry, lint-free cloth to prevent the possibility of con-
taminants entering the outlet control valve section.
Assemble
NOTE: Coat all backup rings and O-rings with a
light coat of clean hydraulic oil to make installation
easier.
NOTE: Perform Step 1 through Step 7 only if the
secondary relief valve was repaired.
1. Install a new backup ring on the secondary re-
lief valve plug. See Figure 6.
2. Install the poppet, washer, and spring into the
secondary relief valve plug.
3. Install a new O-ring on the adjusting nut, and
install the adjusting nut and jam nut assembly
into the secondary relief valve plug using the
number of turns noted during disassembly.
4. While holding the adjusting nut in place,
tighten the jam nut to 24 ±3 N•m (18 ±2 lbf ft).
5. Install a backup ring, O-ring, and backup ring
into the adjusting nut.
6. Install a new O-ring onto the plug. Install the
plug into the adjusting nut.
7. If removed, install secondary relief valve into
outlet control valve section. Tighten relief valve
plug to 45 ±4 N•m (33 ±3 lbf ft). See the section
Pressure Relief Valve Check and Adjustment to
adjust the secondary relief valve and check the
pressure.
Install
NOTE: Coat all O-rings with light coat of clean hy-
draulic oil to make installation easier.
1. Install new O-rings (13, Figure 7 ) into the aux-
iliary valve section. Install the outlet control
valve section on the four tie rods.
2. Install the four nuts on the tie rods. Tighten
the three 13 mm (½ in.) nuts to 24 ±2 N•m (212
±18 lbf in) and the 15 mm (9/16 in.) nut to 45
±4 N•m (33 ±3 lbf ft). See Figure 6.
Auxiliary Control Valve Section
NOTE: There is the possibility of having two auxil-
iary control valve sections depending upon how
many functions are on the lift truck. If the main
control valve is a four-function control valve, there
will be two auxiliary control valve sections. These
sections are repaired the same way.
Remove
1. Remove the outlet control valve section. See
Outlet Control Valve Section, Remove.
2000 SRM 1899 Main Control Valve Repair
7

Figure 7. Auxiliary I and II Control Valve Sections
Main Control Valve Repair 2000 SRM 1899
8

Legend for Figure 7
A. AUXILIARY I CONTROL VALVE SECTION B. AUXILIARY II CONTROL VALVE SECTION
1. PLUG
2. O-RING
3. SPRING
4. WASHER
5. SOCKET HEAD CAPSCREW
6. PROPORTIONAL PRESSURE REDUCING
VALVE (PPRV)
7. SPOOL
8. POPPET
9. AUXILIARY I CONTROL VALVE BODY
10. BACKUP RING
11. AUXILIARY II CONTROL VALVE BODY
12. O-RING
NOTE: For four function control valve, perform
Step 2 and Step 3. For three function control valve,
perform Step 3.
2. Remove the auxiliary II control valve section
from the four tie rods. Remove and discard O-
rings (13, Figure 7) from side of the auxiliary I
control valve section.
3. Remove the auxiliary I control valve section
from the four tie rods. Remove and discard O-
rings from the side of tilt control valve section.
See Figure 7.
Disassemble
NOTE: Disassemble the auxiliary control valve sec-
tion only as needed to accomplish the repairs re-
quired. The disassemble procedures for the auxili-
ary I and II sections are the same. The auxiliary I
section is used in the procedures described below
because it contains the anti-stall valve.
1. Remove four capscrews and two proportional
pressure reducing valves (PPRV) from the aux-
iliary control valve section. Remove and discard
the backup ring, two O-rings, backup ring, and
O-ring from each PPRV. See Figure 7.
2. Remove the plug, spring, washer, and spool
from the auxiliary control valve section. Dis-
card the O-ring on the plug. See Figure 7.
3. Remove the plug, spring, and washer from the
auxiliary control valve section. Discard the O-
ring on the plug. See Figure 7.
4. Remove two plugs, two springs, and two pop-
pets from the auxiliary control valve section.
Discard one O-ring from each plug. See Fig-
ure 7.
Clean
WARNING
Cleaning solvents can be flammable and toxic and
can cause skin irritation. When using cleaning
solvents, always follow the solvent manufactur-
er's recommended safety procedures.
WARNING
Compressed air can move particles so they cause
injury to the user or to other personnel. Make sure
the path of the compressed air is away from all
personnel. Wear protective goggles or a face
shield to prevent injury to the eyes.
1. If all components of the auxiliary control valve
section have been removed, clean the auxiliary
control valve section and components, except
the two PPRVs, using cleaning solvent and dry
using compressed air.
2. If all components have not been removed, clean
the auxiliary control valve section using a lint-
free cloth.
Inspect
Inspect the auxiliary control valve section mating
surfaces and any open bores for damage. If damage
is found, replace the auxiliary control valve section.
If the spool has been removed, inspect the spool
and the bore for damage. If damage to either the
spool or the bore is found, replace the auxiliary con-
trol valve section.
NOTE: If the auxiliary control valve section is not
to be reassembled immediately, coat surfaces with
clean hydraulic oil to prevent the possibility of rust.
Cover the auxiliary control valve section with a
clean, dry, lint-free cloth to prevent the possibility
of contaminants entering the auxiliary control
valve section.
2000 SRM 1899 Main Control Valve Repair
9

Assemble
NOTE: Coat all backup rings and O-rings with a
light coat of clean hydraulic oil to make installation
easier.
NOTE: The assembly procedures for the auxiliary I
and II sections are the same. The auxiliary I sec-
tion is used in the procedures described below be-
cause it contains the anti-stall valve.
1. Install the spool, washer, spring, and plug, with
new O-ring, into the bore of the auxiliary con-
trol valve section. Tighten the plug to 14
±1 N•m (120 ±12 lbf in). See Figure 7.
2. Install the washer, spring, and plug, with new
O-ring, into the auxiliary control valve section.
See Figure 7. Tighten the plug to 14
±1 N•m (120 ±12 lbf in).
3. Install two poppets, two springs, and two plugs,
with new O-rings installed, into the auxiliary
control valve section. See Figure 7. Tighten the
plugs to 81 ±8 N•m (60 ±6 lbf ft).
4. Install the new O-ring, backup ring, two O-
rings, and backup ring on each PPRV. Install
two PPRVs and four capscrews into the auxili-
ary control valve section. See Figure 7. Tighten
the capscrews to 3 ±0.3 N•m (24 ±2 lbf in).
Install
NOTE: Step 1 and Step 2 are for a three-function
control valve. Step 3 through Step 5 are for four-
function control valves.
1. Install new O-rings into the side of tilt control
valve section. Install the auxiliary I control
valve section on the four tie rods. See Figure 8.
2. Install the outlet control valve section. See Out-
let Control Valve Section, Install.
3. Install new O-rings into the side of tilt control
valve section. Install the auxiliary I control
valve section on the four tie rods. See Figure 8.
4. Install the auxiliary II control valve section on
the four tie rods. Install new O-rings into the
side of auxiliary II control valve section.
5. Install the outlet control valve section. See Out-
let Control Valve Section, Install.
6. Install the four nuts on the tie rods on the out-
let control valve section. Tighten the three
13 mm (½ in.) nuts to 24 ±2 N•m (212
±18 lbf in) and the 15 mm (9/16 in.) nut to 45
±4 N•m (33 ±3 lbf ft). See Figure 6.
Tilt Control Valve Section
Remove
1. Remove the outlet control valve section. See
Outlet Control Valve Section, Remove.
2. Remove the auxiliary control valve section(s).
See Auxiliary Control Valve Section, Remove.
3. Remove the tilt control valve section from the
lift/lower control valve section.
4. Remove and discard O-rings from the side of
lift/lower control valve section.
Disassemble
NOTE: Disassemble the tilt control valve section
only as needed to accomplish the repairs required.
1. Remove four socket head capscrews and two
proportional pressure-reducing valves (PPRV)
from the tilt control valve section. See Figure 8.
Remove and discard the backup ring, two O-
rings, backup ring, and O-ring from each
PPRV.
2. Remove the plug, spring, washer, and spool
from the tilt control valve section. Discard the
O-ring on the plug. See Figure 8.
3. Remove the socket head capscrew, spring and
piston from the spool.
4. Remove the plug, spring, and washer from the
tilt control valve section. Discard the O-ring on
the plug. See Figure 8.
5. Remove two plugs, two springs, and two pop-
pets from the tilt control valve section. Discard
one O-ring from each plug. See Figure 8.
Main Control Valve Repair 2000 SRM 1899
10

Clean
WARNING
Cleaning solvents can be flammable and toxic and
can cause skin irritation. When using cleaning
solvents, always follow the solvent manufactur-
er's recommended safety procedures.
WARNING
Compressed air can move particles so they cause
injury to the user or to other personnel. Make sure
the path of the compressed air is away from all
personnel.
Wear protective goggles or a face shield to pre-
vent injury to the eyes.
1. If all components of the tilt control valve sec-
tion have been removed, clean the tilt control
valve section and components, except the two
PPRVs, using cleaning solvent and dry using
compressed air.
2. If not all components have been removed, clean
the tilt control valve section using a lint-free
cloth.
1. PLUG
2. O-RING
3. SPRING
4. WASHER
5. SOCKET HEAD CAPSCREW
6. PISTON
7. PROPORTIONAL PRESSURE-REDUCING
VALVE (PPRV)
8. TILT CONTROL VALVE BODY
9. POPPET
10. BACKUP RING
11. SPOOL
Figure 8. Tilt Control Valve Section
2000 SRM 1899 Main Control Valve Repair
11

Inspect
Inspect the tilt control valve section mating surfa-
ces and any open bores for damage. If damage is
found, replace the tilt control valve section. If the
spool has been removed, inspect the spool and the
bore for the spool for damage. If damage to either
the spool or the bore is found, replace the tilt con-
trol valve section.
NOTE: If the tilt control valve section is not to be
reassembled immediately, coat surfaces with clean
hydraulic oil to prevent the possibility of rust.
Cover the tilt control valve section with a clean,
dry, lint-free cloth to prevent the possibility of con-
taminants entering the tilt control valve section.
Assemble
NOTE: Coat all backup rings and O-rings with a
light coat of clean hydraulic oil to make installation
easier.
1. Install the piston, spring, and socket head cap-
screw in the spool. See Figure 8.
2. Install the spool, washer, spring, and plug, with
new O-ring, into the bore of the tilt control
valve section. Tighten the plug to 14
±1 N•m (120 ±12 lbf in).
3. Install the washer, spring, and plug, with new
O-ring, into the tilt control valve section.
Tighten the plug to 14 ±1 N•m (120 ±12 lbf in).
4. Install two poppets, two springs, and two plugs,
with new O-rings installed, into the tilt control
valve section. Tighten the plugs to 81
±8 N•m (60 ±6 lbf ft). See Figure 8.
5. Install the new O-ring, backup ring, two O-
rings, and backup ring on each PPRV. Install
two PPRVs and four capscrews into the tilt con-
trol valve section. Tighten the capscrews to 3
±0.3 N•m (24 ±2 lbf in).
Install
1. Install new O-rings on the side of lift/lower con-
trol valve section.
2. Install the tilt control valve section on the lift/
lower control valve section.
3. Install the auxiliary I and II (if equipped) con-
trol valve sections. See Auxiliary Control Valve
Section, Install.
4. Install the outlet control valve section. See Out-
let Control Valve Section, Install.
5. Install the four nuts on the tie rods of the outlet
control valve section. Tighten the three
13 mm (½ in.) nuts to 24 ±2 N•m (212
±18 lbf in) and the 15 mm (9/16 in.) nut to 45
±4 N•m (33 ±3 lbf ft). See Figure 6.
Lift/Lower Control Valve Section
Remove
1. Remove the outlet control valve. See Outlet
Control Valve Section, Remove.
2. Remove the auxiliary control valve section(s).
See Auxiliary Control Valve Section, Remove.
3. Remove the tilt control valve section. See Tilt
Control Valve Section, Remove.
4. Remove lift/lower control valve section from
transition control valve section.
5. Remove and discard O-rings from side of transi-
tion control valve section.
Disassemble
NOTE: Disassemble the lift/lower control valve sec-
tion only as needed to accomplish the repairs re-
quired.
1. Remove four socket head capscrews and two
proportional pressure-reducing valves (PPRV)
from top and bottom of lift/lower control valve
section. See Figure 9. Remove and discard the
O-rings and backup rings from each PPRV.
2. Remove the socket head plug from bottom of
lift/lower control valve section. Remove and dis-
card O-ring from plug. See Figure 9.
3. Remove the spring, spool, piston, backup ring,
and washer from the bottom of lift/lower control
valve section. See Figure 9.
Main Control Valve Repair 2000 SRM 1899
12

4. Remove the socket head plug, spring, and
washer from top of lift/lower control valve sec-
tion. Remove and discard O-ring from plug. See
Figure 9.
5. Remove load check valve, spring, O-ring, and
poppet. Discard O-ring. Remove and discard O-
ring from load check valve. See Figure 9.
Clean
WARNING
Cleaning solvents can be flammable and toxic and
can cause skin irritation. When using cleaning
solvents, always follow the solvent manufactur-
er's recommended safety procedures.
WARNING
Compressed air can move particles so they cause
injury to the user or to other personnel. Make sure
the path of the compressed air is away from all
personnel. Wear protective goggles or a face
shield to prevent injury to the eyes.
1. If all components of the lift/lower control valve
section have been removed, clean the lift/lower
control valve section and components, except
the two PPRVs, using cleaning solvent and dry
using compressed air.
2. If all components have not been removed, clean
the lift/lower control valve section using a lint-
free cloth.
A. TOP B. BOTTOM
1. PROPORTIONAL PRESSURE REDUCING
VALVE
2. SOCKET HEAD PLUG
3. SPRING
4. POPPET
5. O-RING
6. SPOOL
7. LOAD CHECK VALVE
8. PISTON
9. BACKUP RING
Figure 9. Lift/Lower Control Valve Section
2000 SRM 1899 Main Control Valve Repair
13

Inspect
Inspect the lift/lower control valve section mating
surfaces and any open bores for damage. If damage
is found, replace the lift/lower control valve section.
If the spool has been removed, inspect the spool
and the bore for damage. If damage to either the
spool or the bore is found, replace the lift/lower con-
trol valve section.
NOTE: If the lift/lower control valve section is not
to be reassembled immediately, coat surfaces with
clean hydraulic oil to prevent the possibility of rust.
Cover the lift/lower control valve section with a
clean, dry, lint-free cloth to prevent the possibility
of contaminants entering the lift/lower control
valve section.
Assemble
1. Install new O-ring on load check valve. Install
poppet, O-ring, spring, and load check valve on
lift/lower control valve section. See Figure 9.
2. Install new O-ring on plug. Install washer,
spring, and socket head plug on top of lift/lower
control valve section. See Figure 9. Tighten
plug to 81 ±8 N•m (60 ±6 lbf ft).
3. Install washer, backup ring, piston, spool, and
spring on bottom of lift/lower control valve sec-
tion. See Figure 9.
4. Install new O-ring on plug. Install socket head
plug on bottom of lift/lower control valve sec-
tion. See Figure 9. Tighten plug to 81
±8 N•m (60 ±6 lbf ft).
5. Install backup rings and O-rings on two propor-
tional pressure-reducing valves (PPRV). Install
two PPRV and four socket head capscrews in
top and bottom of lift/lower control valve sec-
tion. Tighten capscrews to 14 ±1 N•m (120
±12 lbf in).
Install
1. Install new O-rings on side of transition control
valve section.
2. Install lift/lower control valve section on transi-
tion control valve section.
3. Install the tilt control valve section. See Tilt
Control Valve Section, Install.
4. Install the auxiliary control valve section. See
Auxiliary Control Valve Section, Install.
5. Install the outlet control valve section. See Out-
let Control Valve Section, Install.
Transition Section
Remove
1. Remove the outlet control valve section. See
Outlet Control Valve Section, Remove.
2. Remove the auxiliary control valve section(s).
See Auxiliary Control Valve SectionRemove.
3. Remove the tilt control valve section. See Tilt
Control Valve Section, Remove.
4. Remove the lift/lower control valve section. See
Lift/Lower Control Valve Section, Remove.
5. Remove four tie rods from the transition control
valve section.
Disassemble
CAUTION
The transition section is equipped with a clipper
relief valve. DO NOT disassemble or adjust the
clipper relief valve. Removing the tamper proof
cap and disassembling and/or adjusting the clip-
per relief valve will void and/or cancel any warran-
ties. Contact your dealer for more information.
CAUTION
When removing the emergency load lowering
valve, use care to not damage the tip of the emer-
gency load lowering valve.
NOTE: Disassemble the transition control valve
section only as needed to accomplish the repairs re-
quired.
Remove the emergency load lowering valve from
the transition section. Remove and discard the O-
ring from valve. See Figure 10.
Clean
Clean the transition control valve section using a
lint-free cloth.
Main Control Valve Repair 2000 SRM 1899
14