Thomas 95 Operating instructions

95/105 /
115
Publication No. 46847
Date: February, 2001
REPAIR MANUAL
THOMAS

2
THOMAS EQUIPMENT LIABILITY WARRANTY
THE WARRANTY IS THE ONLY OBLIGATION OF THOMAS OR A THOMAS DEALER TO THE
PURCHASER OR ANYONE ELSE CONCERNING A PRODUCT, ITS SERVICE, ITS USE OR
PERFORMANCE OR ITS LOSS OF USE OR FAILURE TO PERFORM. NEITHER THOMAS NOR A
THOMAS DEALER HAVE MADE AND NEITHER WILL MAKE ANY OTHER EXPRESSED OR IMPLIED
REPRESENTATION, WARRANTY OR AGREEMENT CONCERNING A PRODUCT. NEITHER THOMAS
NOR A THOMAS DEALER HAVE MADE OR WILL MAKE ANY REPRESENTATION, WARRANTY OR
AGREEMENT CONCERNING A PRODUCTS MERCHANTABILITY OR OTHER QUALITY, ITS
SUITABILITY FOR PURCHASER’S PURPOSE (EVEN IF A PURCHASER HAS INFORMED THOMAS OR A
THOMAS DEALER OF THAT PURPOSE), ITS DURABILITY, PERFORMANCE OR OTHER CONDITION.
EVEN IF THOMAS OR A THOMAS DEALER WAS ADVISE OF THE POSSIBILITY OF SUCH LOSS,
NEITHER THOMAS NOR A THOMAS DEALER WILL BE LIABLE TO PURCHASER OR ANYONE ELSE
FOR ANY INDIRECT, INCIDENTAL CONSEQUENTIAL, PUNITIVE, ECONOMIC, COMMERCIAL, OR
SPECIAL LOSS WHICH IS IN ANY WAY ASSOCIATED WITH A PRODUCT. THIS INCLUDES ANY LOSS OF
USE OR NON-PERFORMANCE OF A PRODUCT, ANY REPLACEMENT RENTAL OR ACQUISITION COST,
ANY LOSS OF REVENUE OR PROFITS, ANY FAILURE TO REALIZE EXPECTED SAVINGS, ANY
INTEREST COSTS, ANY IMPAIRMENT OF OTHER GOODS, ANY INCONVENIENCE OR ANY LIABILITY
OF PURCHASER TO ANY OTHER PERSON.
PURCHASER MAY NOT ATTEMPT TO ENLARGE ITS RIGHTS UNDER THE WARRANTY BY MAKING
A CLAIM FOR INDEMNITY, FOR BREACH OF CONTRACT, FOR BREACH OF COLLATERAL WARRANTY,
FOR A TORT (INCLUDING NEGLIGENCE, MISREPRESENTATION OR STRICT LIABILITY) OR BY
CLAIMING ANY OTHER CAUSE OF ACTION.
THE WARRANTY IS A CONDITION OF SALE OF THE PRODUCT TO PURCHASER AND WILL
THEREFORE APPLY EVEN IF PURCHASER ALLEGES THAT THERE IS A TOTAL FAILURE OF THE
PRODUCT.
N.B. Read and practice your Thomas operating and servicing instructions. Failure to do this may void your warranty.
Publication Number 46847
February 2001

3
It is important when ordering replacement parts or making a service inquiry to provide both the
model number and serial number of your Thomas loader. The serial number plate is located at the
rear of the machine on the right hand side fuel tank. In the event that the serial number plate is
missing, the model number and serial number are both stamped into the main frame inside the rear
door, next to the hydraulic control valve.
FOREWORD
S / N Stamp location
C2347
S / N Tag location

4
Practically all Service work involves the need to drive the
loader. The Owner’s / Operator’s Manual, supplied with
each loader, contains safety precautions relating to
driving, operating and servicing that loader. These
precautions are as applicable to the service technicians as
they are to the operator and should be read, understood
and practiced by all personnel.
Prior to undertaking any maintenance, repair, overhaul,
dismantling or re-assembly operations, whether within the
shop facility or “out in the field”, may have an effect
upon safety, not only upon the mechanic carrying out the
work but also upon bystanders.
PERSONAL CONSIDERATIONS
*CLOTHING
The wrong clothing or carelessness in dress can
cause accidents. Check to see that you are
suitably clothed. Some jobs require special
protective equipment.
*SKIN PROTECTION
Used motor oil may cause skin cancer. Follow
work practices that minimize the amount of skin
exposed and length of time used oil stays on
your skin.
*EYE PROTECTION
The smallest eye injury may cause loss of vision.
Injury can be avoided by wearing eye protection
when engaged in chiseling, grinding, welding,
painting and any other task that involves foreign
matter.
*BREATHING PROTECTION
Fumes, dust and paint spray are unpleasant and
harmful. These can be avoided by wearing
respiratory protection.
*HEARING PROTECTION
Loud noise may damage your hearing and the
longer the exposure the greater the risks of
hearing damage. Always wear hearing protection
when working around loud machinery.
*HAND PROTECTION
It is advisable to use a protective cream before
work to prevent irritation and skin
contamination. After work, clean your hands
with soap and water. Solvents such as white
spirits, paraffin, etc. may harm the skin.
*FOOTPROTECTION
Substantial or protective footwear with
reinforced toecaps will protect the feet from
falling objects. Additional oil-resistant
soles will help to avoid spilling.
*SPECIALCLOTHING
For certain work it may be necessary to wear
flame or acid resistant clothing.
EQUIPMENT CONSIDERATIONS
*MACHINE GUARDS
Before using any machine, check to ensure that
the machine guards are in position and
serviceable. These guards not only prevent parts
of the body or clothing coming in contact with
the moving parts of the machine but also ward
off objects that might fly off the machine and
cause injury.
*LIFTING APPLIANCES
Always ensure that lifting equipment, such as
chains, slings, lifting brackets, hooks and eyes
are thoroughly checked before use. If in doubt,
select stronger equipment. Never stand under a
suspended load or raised implement.
*COMPRESSED AIR
The pressure from a compressed air line is often
as high as 100 PSI (6.9 Bar). Any misuse may
cause injury.
Never use compressed air to blow dust, filing
dirt, etc. away from your work area unless the
correct type of nozzle is fitted.
Compressed air is not a cleaning agent. It will
only move dust etc. from one place to another.
Look around before using an air hose as
bystanders may get grit into their eyes, ears and
skin.
Avoid injury through incorrect handling of
components. Make sure your are capable of lifting
the object. If in doubt, get help.
SAFETY PRECAUTIONS
CAUTION

5
*HAND TOOLS
Many cuts, abrasions and injuries are caused by
defective tools. Never use the wrong tool for the
job as this leads either to some injury or to a
poor job done.
Never Use:
A hammer with a loose or split handle.
Spanners or wrenches with splayed or worn
jaws.
Wrenches or files as hammers; drills or
clevis pins or bolts as punches.
For removing or replacing hardened pins use a
copper or brass drift rather than a hammer.
For dismantling, overhaul and assembly of major
and sub-components always use the Special
Service Tools recommended. These will reduce
the work effort, labor time and the repair cost.
Always keep tools clean and in good working
order.
*ELECTRICITY
Electricity has become so familiar in day to day
usage that it’s potentially dangerous properties
are often overlooked. Misuse of electrical
equipment can endanger life.
Before using any electrical equipment,
particularly portable appliances, make a visual
check to ensure that the cable is not worn or
frayed and that the plugs, sockets etc. are intact.
Make sure you know where the nearest isolating
switch for your equipment is located.
GENERAL CONSIDERATIONS
*SOLVENTS
Use only cleaning fluids and solvents that are
known to be safe. Certain types of fluids can
cause damage to components such as seals, etc.
and can cause skin irritation. Solvents should be
checked that they are suitable not only for the
cleaning of components and individual parts but
also that they do not affect the personal safety of
the user.
*HOUSEKEEPING
Many injuries result from tripping or slipping
over, or on, objects or materials left lying around
by a careless worker.
Prevent these accidents from occurring. If you
notice a hazard, don’t ignore it, remove it.
A clean, hazard free place of work improves the
surroundings and daily environment for
everybody.
*FIRE
Fire has no respect for persons or property. The
destruction that a fire can cause is not always
fully realized. Everyone must be constantly on
guard.
- Extinguish matches, cigars, cigarettes etc.
before throwing them away.
- Work cleanly, disposing of waste material into
proper containers.
- Locate all the fire extinguishers and ensure all
personnel know how to operate them.
- Do not panic, warn those near and sound the
alarm.
- Do not allow or use an open flame near the
loader fuel tank, battery or component parts.
*FIRST AID
In the type of work that mechanics are engaged
in, things such as dirt, grease, fine dust etc. all
settle upon the skin and clothing. If a cut,
abrasion or burn is disregarded it may be found
that a septic condition has formed in a short time.
What appears at first to be trivial could become
painful and injurious. It only takes a few minutes
to have a fresh cut dressed but it will take longer
if you neglect it.
*CLEANLINESS
Cleanliness of the loader hydraulic system is
essential for optimum performance. When
carrying out service and repairs, plug all hose
ends and components connections to prevent dirt
entry.
Clean the exterior of all components before
carrying out any form of repair. Dirt and abrasive
dust can reduce the efficiency and working life
of a component and lead to costly replacement.
Use of a high pressure washer or steam cleaner is
recommended.
SAFETY PRECAUTIONS

6
OPERATIONAL CONSIDERATIONS
*Stop the engine, if at all possible, before
performing any service.
*Place a warning sign on loaders which, due to
service or overhaul, would be dangerous to start.
Disconnect the battery leads if leaving such a
unit unattended.
*Do not attempt to start the engine while standing
beside the loader or attempt to bypass the safety
starting system.
*Avoid prolonged running of the engine in a
closed building or in an area with inadequate
ventilation as exhaust fumes are highly toxic.
*Always turn the radiator cap to the first stop to
allow pressure in the system to dissipate when
the coolant is hot.
*Never work beneath a loader which is on soft
ground. Always take the unit to an area which
has a hard working surface, preferably concrete.
*If it is found necessary to raise the loader for
ease of maintenance, make sure that safe and
stable supports are installed beneath the main
frame before commencing work.
*Use footsteps or working platforms when
servicing those areas of the loader that are not
within easy reach.
*Before loosening any hoses or tubes, switch off
the engine, remove all pressure in the lines by
operating the foot pedals several times. This will
remove the danger of personal injury by oil
pressure.
*Prior to pressure testing, make sure all the hoses
and connectors on both the loader and on the test
machine are in good condition and tightly sealed.
Pressure readings must be taken with the gauges
specified. The correct procedure should be
rigidly observed to prevent damage to the system
or the equipment and to eliminate the possibility
of personal injury.
*Always lower equipment to the ground when
leaving the loader.
*If high lift attachments are installed on a loader,
beware of overhead power and telephone lines
when travelling. Drop attachment near to ground
level to increase stability and minimize risks.
*Do not park or attempt to service a loader on an
incline. If unavoidable, take extra care and block
the wheels.
*Escaping hydraulic / diesel fluid under pressure
can penetrate the skin causing serious injury. Do
not use your hand to check for leaks. Use a piece
of cardboard or paper to search for leaks. Stop
the engine and relieve pressure before connecting
or disconnecting lines. Tighten all connections
before starting the engine or pressurizing the
lines. If any fluid is injected into the skin, obtain
medical attention immediately.
*Prior to removing wheels and tires from a loader,
check to determine whether additional ballast
(liquid or weight) has been added. Seek
assistance and use suitable equipment to support
the weight of the wheel assembly.
*When inflating tires beware of over inflation.;
constantly check the pressure. Over inflation can
cause tires to burst and result in personal injury.
*Safety precautions are very seldom the figment
of someone’s imagination. They are the result of
sad experience where most likely someone has
paid dearly through personal injury.
*Heed these precautions and you will protect
yourself accordingly. Disregard them and you
will duplicate the sad experiences of others.
SAFETY PRECAUTIONS

7
SERVICE TECHNIQUES
A. SERVICE SAFETY
Appropriate service methods and proper repair
procedures are essential for the safe, reliable
operation of all motor vehicles as well as the
personal safety of the individual doing the work. This
shop manual provides general directions for
accomplishing service and repair work with
tested effective techniques. Following them will help
assure reliability.There are numerous variations in
procedures, techniques, tools and parts for servicing
vehicles as well as in the skill of the individual doing the
work. This manual cannot possibly anticipate all such
variations and provide advice or cautions as to each.
Accordingly, anyone who departs from the instructions
provided in this manual must first establish that he or she
compromises neither his personal safety nor the vehicle
integrity by his choice of methods, tools or parts.
B. SERVICE TECHNIQUES
Clean the exterior of all components before carrying out
any form of repair. Dirt and abrasive dust can reduce the
efficient working life of a component and lead to costly
replacement.
Use cleaning fluids which are known to be safe. Certain
types of fluid can cause damage to O rings and cause skin
irritation. Solvents should be checked that they are
suitable for the cleaning of components and also that they
do not risk the personal safety of the user.
Time spent on the preparation and cleanliness of working
surfaces will pay dividends in making the job easier and
safer and will result in overhaul components being more
reliable and efficient in operation.
Replace O rings, seals or gaskets whenever they are
disturbed. Never mix new and old seals and O rings,
regardless of condition. Always lubricate new seals and O
rings with hydraulic oil before installation.
When replacing component parts use the correct tool for
the job.
C. HOSES AND TUBES
Always replace hoses and tubes if the end connections are
damaged. Be sure any hose installed is not kinked or
twisted.
When installing a new hose, loosely connect each end and
make sure the hose takes up the designed position before
tightening the connection. Clamps should be tightened
sufficiently to hold the hose without crushing and to
prevent chafing.
The hoses are the arteries of the unit; be sure they are in
good condition when carrying out repairs or maintenance
otherwise the machines output and productivity will be
affected.
After hose replacement to a moving component, check
that the hose does not foul by moving the component
through the complete range of travel.
Hose connections which are damaged, dented , crushed or
leaking, restrict oil flow and the productivity of the
components being served. Connectors which show signs
of movement from the original swaged position have
failed and will ultimately separate completely.
A hose with a chafed outer cover will allow water entry.
Concealed corrosion of the wire reinforcement will
subsequently occur along the hose length with resultant
hose failure.
Ballooning of the hose indicates an internal leakage due
to structural failure. This condition rapidly deteriorates
and total hose failure soon occurs.
Kinked, crushed, stretched or deformed hoses generally
suffer internal structural damage which results in oil
restriction, a reduction in the speed of operation and
ultimate hose failure.
Free moving, unsupported hoses must never be allowed to
touch each other or related working surfaces. This causes
chafing which reduces hose life.
D. PRESSURE TESTING
Prior to pressure testing, be sure all hoses are in good
condition and all connections tight. Pressure readings
must be taken with gauges of specified pressure readings.
The correct procedure should be rigidly observed to
prevent damage to the system or the equipment and to
eliminate the possibility of personal injury.
SAFETY PRECAUTIONS

8
E. BEARINGS
Bearings which are considered suitable for further service
should be cleaned in a suitable solvent and immersed in
clean lubricating oil until required.
Installation of a bearing can be classified into two (2)
ways:
press fit on rotating parts such as shafts and gears,
push fit into static locations such as reduction gear
houses.
Where possible, always install the bearing onto the
rotating components first. Use the correct tools or a press
to install a bearing or bushing. In the absence of the
correct tools or press, heat the bearing and / or casing in
hot oil to assist the installation of the bearing.
When bearings or bushings are removed, always carefully
check that the bearing is free from discoloration and signs
of overheating. Also check for mechanical damage such
as excessive clearance, nicks and scuffing. If in doubt,
replace the bearings or bushings.
Bearings should never be removed unless absolutely
necessary. Always use the recommended puller to reduce
the risk of bearing or related component failure.
These bearings and bushings are subjected, in normal
operation, to high working loads and adverse conditions.
Be sure during normal routine servicing, maintenance or
repair that bearings are given the right attention and are
installed with care.
F. BOOM SUPPORTS
For safety while performing regular service or
maintenance work, the loader is equipped with boom
supports.
The boom supports, when extended, prevent the boom
arms from dropping if hydraulic pressure is relieved or
the foot control pedals are accidentally cycled.
To operate the boom supports, first remove any bucket or
attachment from the quick - tach; raise the boom arms to
full height and shut off the engine. Raise the boom
handles up and push out toward the boom arms to extend
the boom supports. (fig. C729, C321)
SAFETY PRECAUTIONS
To avoid personal injury, service the loader with the
boom arms down and the bucket or attachment
lowered to the ground. If it is necessary to service the
loader with the boom arms raised, be sure to engage
the boom supports. Never work under or around a
loader with raised boom arms without the boom
supports engaged.
C729
WARNING

9
THOMAS

10
TABLE OF CONTENTS
Section 1 Hydraulic System
Hydraulic Circuit...............................................................................1.1
Gear Pump .........................................................................................1.2
Control Valve.....................................................................................1.3
Hydraulic Cylinders...........................................................................1.4
Oil Filter.............................................................................................1.5
Oil Cooler..........................................................................................1.6
Oil Reservoir......................................................................................1.7
Trouble Shooting ...............................................................................1.8
Torque Chart ......................................................................................1.9
Section 2 Hydrostatic Drive System
Hydrostatic Drive Circuit..................................................................2.1
Specifications.....................................................................................2.2
General Information...........................................................................2.3
Trouble Shooting ...............................................................................2.4
Pressure Tests.....................................................................................2.5
Towing Procedure..............................................................................2.6
Flushing The Hydraulic System ........................................................2.7
Start - up Procedure ...........................................................................2.8
Gear Pump Replacement...................................................................2.9
Tandem Pump Replacement ..............................................................2.10
Tandem Pump Parts Diagram............................................................2.11
Drive Motor .......................................................................................2.12
Section 3 Final Drive
Specifications and Maintenance ........................................................3.1
Lubrication.........................................................................................3.2
Drive Chain........................................................................................3.3
Drive Motor Sprocket........................................................................3.4
Axle Assembly...................................................................................3.5
Trouble Shooting ...............................................................................3.6
Section 4 Controls
Steering..............................................................................................4.1
Foot Pedals.........................................................................................4.2
Hand Controls....................................................................................4.3
Throttle...............................................................................................4.4
Restraint Bar......................................................................................4.5
Parking Brake ....................................................................................4.6
Trouble Shooting ...............................................................................4.7

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TABLE OF CONTENTS
Section 5 Electrical
General Information...........................................................................5.1
Wiring Schematics.............................................................................5.2
Instrumentation..................................................................................5.3
Ignition Switch...................................................................................5.4
Engine Glow Plugs............................................................................5.5
Battery................................................................................................5.6
Electrical Panel..................................................................................5.7
Starter Circuit.....................................................................................5.8
Charging Circuit ................................................................................5.9
Safety Circuit .....................................................................................5.10
Cooling Fan Circuit ..........................................................................5.11
Auxiliary Circuit ................................................................................5.12
Accessory Circuit...............................................................................5.13
Trouble Shooting ...............................................................................5.14
Section 6 Main Frame
Quick - Tach.......................................................................................6.1
Boom Arms........................................................................................6.2
Boom Support....................................................................................6.3
ROPS .................................................................................................6.4
Rear Door...........................................................................................6.5
Section 7 Engine
Maintenance.......................................................................................7.1
Cylinder Head....................................................................................7.2
Replacement.......................................................................................7.3
Specifications.....................................................................................7.4
Trouble Shooting ...............................................................................7.5
Section 8 Maintenance & Specifications
Maintenance.......................................................................................8.1
Trouble Shooting ...............................................................................8.2
Special Tools ......................................................................................8.3
Specifications.....................................................................................8.4
Conversion Charts..............................................................................8.5

12
THOMAS

1-1
SECTION 1 HYDRAULIC SYSTEM
Hydraulic Circuit 1.1
Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-2
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-3
Maintenance Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-3
General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-4 ~ 5
Gear Pump 1.2
Replacing the Gear Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-6
Start - up Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-7
Testing (See control valve relief). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-14 ~ 15
Control Valve 1.3
Testing / Adjusting the Relief Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-8
Control Valve Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-9
Control Valve Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .pg. 1-10
Exploded Illustration (to S / N LC001080) . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-12 ~ 13
Exploded Illustration (S / N LC001081 onward) . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-15
Control Valve Disassembly / Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-16 ~ 25
Hydraulic Cylinders 1.4
General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-26
Testing Piston Seals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-27
Lift Cylinder Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-28
Tilt Cylinder Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-29
Cylinder Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-30 ~ 31
Cylinder Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-32
Cylinder Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-32 ~ 33
Hydraulic Oil Filter 1.5
General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-34
Filter Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-34
Hydraulic Oil Cooler 1.6
General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-35
Oil Cooler Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-35
Hydraulic Oil Reservoir 1.7
General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-36
Checking the Oil Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-36
Adding Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-36
Servicing the Reservoir . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-37
Trouble Shooting 1.8
Trouble Shooting Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-38 ~ 39
Torque Chart 1.9
Hydraulic Hose and Fitting Torque Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pg. 1-39
1

1-2
HYDRAULIC CIRCUIT 1.1
C1008
Lift Cylinders Tilt CylindersAuxiliary Couplers
Control Valve Outlet
NOTE: Foot pedal control operated machine illustrated. Hydraulic fluid comes out the port closest to the spool
end of the valve when the spool is pushed in.
Hydraulic fluid received at the fixed end of the cylinder
pushes it out. When the hydraulic cylinder receives fluid
at the ram (rod) end, it retracts.
1

1-3
SPECIFICATIONS & MAINTENANCE 1.1
Pump Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gear, 0.61 cu. in. (11cc)
Pump Brand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sauer Sundstrand
Pump Capacity (theoretical) . . . . . . . . . . . . . . . . . . . . . . . . . 8.7 GPM (33 LPM)
Rated Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3000 RPM
Control Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Parallel Type
Main Relief Pressure, +/- 50PSI (3.5 Bar) . . 2150 PSI (148 Bar) @ Zero Flow
Reservoir Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 L (9 gallons)
Fluid Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10W30 API SE / CD Oil
Reservoir Filtration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Micron
System Filtration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Micron
Lift Cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (2) 2’’ Bore Diameter
Lift Cylinder Rods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.125’’ Diameter
Tilt Cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (2) 2’’ Bore Diameter
Tilt Cylinder Rods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.125’’ Diameter
Lift Cycle + / - 1.5 seconds (Up / Down) . . . . . . . . . . . . . . . . . . . . . . 5.4 / 3.54
Tilt Cycle + / - 1.5 seconds (Up / Down) . . . . . . . . . . . . . . . . . . . . . 2.35 / 3.06
Allowable Drop, Measured at the Cylinder Rod, Engine Off,
@ Rated Capacity and Operating Temperature . . . . . . 1.5’’ (38mm) / 3 Minutes
Maintenance Schedule . . . . . . . . . First (HRS) . . . . Every (HRS)
Oil level check . . . . . . . . . . . . . . . . . . . . . . . . . 8. . . . . . . . . . . . . . . . . . 8
Oil filter change . . . . . . . . . . . . . . . . . . . . . . . . 50 . . . . . . . . . . . . . . . . . 150
General system check (leaks etc.) . . . . . . . . . . 8. . . . . . . . . . . . . . . . . . 8
Lubricate (grease pivots) . . . . . . . . . . . . . . . . . 8. . . . . . . . . . . . . . . . . . 8
Reservoir filter change . . . . . . . . . . . . . . . . . 1000 . . . . . . . . . . . . . . . 1000
Hydraulic oil change . . . . . . . . . . . . . . . . . . . 1000 . . . . . . . . . . . . . . . 1000
1
Hydraulic Specifications

1-4
GENERAL INFORMATION 1.1
Oil is drawn from the hydraulic oil reservoir through a
100 micron element. From there it travels to the main
hydraulic pump. (fig. C2353).
The hydraulic pump is a gear type which is driven by a
shaft and coupler through the hydrostatic drive pump at
engine speed. The oil then flows from the gear pump to
the hydraulic control valve. (fig. C2347).
The hydraulic control valve is equipped with an
adjustable relief valve which is adjusted to 2150 PSI (148
Bar). The control valve is a parallel type with 3 spools
(banks). The various spools activate the boom, bucket and
auxiliary hydraulic functions.
When the spools are in neutral, oil flows from the
hydraulic gear pump, through the control valve and
returns to the 10 micron hydraulic filter. From the
hydraulic filter, the fluid flows to charge the tandem
hydrostatic pump and pressurize the hydraulic brake
release system and then back to the hydraulic reservoir.
Each control valve section spool end contains a centering
spring which returns the spool to neutral when the foot
pedal, or control handle, is released. (fig. C2350).
The boom section, on foot control operated loaders, has a
detent mechanism to hold the spool in the float position.
The auxiliary section is operated by foot pedal operation,
or may have an optional electrical solenoid operated
control, and may be engaged momentarily by the control
lever mounted switch, forward or reverse, or by engaging
the dash mounted toggle switch for constant power in the
forward direction only.
The system relief valve operates whenever a hydraulic
function has been restricted or over loaded. (fig. C2248).
To protect against excessive pressure build up, the relief
valve opens and allows oil to return to the return outlet.
The system relief valve is adjustable, and is preset at
2150 PSI. (148 Bar)
Gear pump location
Control valve location
Relief valve
1
C2353
C2347
Spring return
C2348
C2350
Hydraulic System

1-5
GENERAL INFORMATION 1.1
1
THOMAS

1-6
GEAR PUMP 1.2
Start the gear pump removal procedure by removing any
attachment, raising the boom arms and engaging the
boom support pins. Shut off the engine.
1Remove the seat and hydrostatic shield. (fig. C2358,
C2360)
2Attach a vacuum system to the hydraulic oil reservoir
filler location. Or drain the oil reservoir. Seal the threads
on the drain plug, if removed, with teflon tape or a liquid
form of pipe sealant before installing.
3Disconnect the hydraulic hoses from the gear pump.
(fig. C2353) Remove the pump fittings. Cap all open
hoses to prevent contamination. After capping ends you
may unhook vacuum system from oil reservoir.
4Remove the 2 bolts holding the gear pump to the
hydrostatic tandem section. (fig. C2353) Remove the gear
pump. Check the seal. Replace if required.
5Replace gear pump in reverse order.
6Start the engine and check for leaks. Do not use your
hands to find leaks.
7Check the fluid level in the hydraulic oil reservoir
and replenish as required. (fig. C2354)
8Follow the Start Up Procedure upon completing
repairs. See next page.
C2358
C2360
C2353
C2354
Gear pump
Screws
Hydrostatic shield
Oil level
Replacement
1
WARNING
To prevent personal injury, never work under the
boom arms without the boom supports engaged.
WARNING
Use caution when dealing with fluid under pressure.
Escaping fluid under pressure can penetrate the skin
and cause serious injury.
IMPORTANT
If gear pump replacement is being done because of
failure, the hydraulic system and oil should be
checked for contamination. See section 2.7.
IMPORTANT
When making repairs to the hydraulic system, keep
the work area and parts clean. Use caps and plugs on
all open lines and ports. Follow the torque chart
when tightening lines and fittings.
Hyd. lines

1-7
GEAR PUMP 1.2
1
Start up Procedure
1Mount the gear pump to the loader. (fig. C2353)
2Connect the hydraulic lines. Torque fittings and lines
according to the torque chart section 1.8.
3Start the pump and run for 3 minutes each @
a. Half speed at zero flow
b. Half speed, intermittently loaded to 500 psi (35
bar)
c. Full speed, intermittently loaded to 1000 psi (69
bar)
4Check for leaks.
5Check flow and pressure at rated speed as outlined in
section 1.3.
C2352
Intermittently load the gear pump at start up
Flow test meter p / n 960456
WARNING
Use caution when dealing with fluid under
pressure. Escaping fluid under pressure can
penetrate the skin and cause serious injury. Never
use your hands to check for system leaks.
C2353
Screws
Hyd. lines
IMPORTANT
Be sure the hydraulic oil reservoir is at the proper
level before performing test.

1-8
CONTROL VALVE 1.3
Testing and Adjusting the Relief Valve Pressure
NOTE: This test also checks the status of the gear
pump capacities.
Hoses and gauges required for this test must be capable
of withstanding 3000 PSI (207 Bar) continuous pressure,
and hydraulic flow meter capable of measuring 30 gallons
per minute. (113 LPM)
1The female coupler attached to the loader provides
the power out when the auxiliary control is engaged. (fig.
C2351) Connect the flow meter and pressure gauge inlet
side to match the power out of the female auxiliary
coupler to prevent meter and gauge damage. Be sure to
connect a return line to the male auxiliary hydraulic quick
coupler. Install the flow meter / pressure tester to the
auxiliary hydraulic quick couplers. (fig. C2352)
2Start the engine and engage the auxiliary hydraulic
system. Increase the engine speed to full operating RPM.
(See Section 7 for checking and adjusting engine speed to
3000 RPM plus or minus 25 RPM)
3Turn the flow control valve on the flow meter to
restrict the oil flow down to 2 GPM. (7.5 LPM) As you
are turning the flow control valve, watch the pressure
gauge and make sure it does not go over 3000 PSI.(207
Bar) Stop further adjustment immediately if the reading
goes over this setting. Shut off the auxiliary hydraulic
system and shut off the engine. Move to step 6 to make
initial setting.
4Repeat steps 2 and 3 if necessary. Allow the loader to
operate at this setting until the oil temperature has
increased to 160° F (71ºC), operating temperature.
5Turn the flow control valve further to restrict the oil
flow to no flow. (Zero) Correct pressure setting is 2150
PSI +/- 100 PSI. (148 Bar, +/-6.9 Bar)
6If adjustment is necessary, shut down the auxiliary
hydraulic system, shut off the engine and return the flow
control valve to the open position. Locate the control
valve in the engine compartment.
7Loosen the jam nut on the relief valve adjusting
screw and turn the screw clockwise, counting the turns,
until the screw bottoms out. (fig. C2348)
8Turn the screw back out lesser turns than you turned
in to increase pressure, or out more turns to decrease
pressure.
9Retake the pressure readings by performing steps 2
through 5. If necessary make further adjustments by
repeating steps 6 through 9.
NOTE: If inadequate pressure and / or flow is not
available, the gear pump could be failing or the inlet
to the gear pump is restricted.
C2351
1
C2348
Relief valve
Jam nut
Pressure out
CAUTION
Adjusting the relief valve setting too high may cause
damage to the gear pump.
Auxiliary couplers
C2352
WARNING
To prevent personal injury or damage to the loader,
do not adjust the relief valve while the engine is
operating.