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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
®
310-2200 EZT
Integrated Zero-Turn Transaxle
Service and Repair Manual
BLN-51856
December 2008
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Page 2
Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
TABLE OF CONTENTS
Section Page
Foreword............................................................................................................................. 1
Description and Operation ................................................................................................ 2
Introduction .................................................................................................................................................. 2
General Description ..................................................................................................................................... 2
Hydraulic Schematic.................................................................................................................................... 3
External Features 310-2200 ......................................................................................................................... 4
Technical Specifications ............................................................................................................................... 5
Product Identification ................................................................................................................................... 5
Safety .................................................................................................................................. 6
Personal Safety ........................................................................................................................................... 6
Tool Safety................................................................................................................................................... 6
Work Area Safety ........................................................................................................................................ 6
Servicing Safety ........................................................................................................................................... 6
Troubleshooting .................................................................................................................7
Service and Maintenance .................................................................................................. 8
External Maintenance .................................................................................................................................. 8
Service and Maintenance Procedures .......................................................................................................... 8
Fluids .......................................................................................................................................................... 8
Fluid Volume and Level ................................................................................................................................8
Fluid Change Procedure .............................................................................................................................. 9
Purging Procedures ................................................................................................................................... 10
Return to Neutral Setting ........................................................................................................................... 11
Repair ................................................................................................................................ 13
How To Use This Section ........................................................................................................................... 13
General Instructions ................................................................................................................................... 13
Transaxle Removal ..................................................................................................................................... 13
Limited Disassembly ................................................................................................................................. 13
Tools and Torques ...................................................................................................................................... 14
Control Arm and Bypass Arm ..................................................................................................................... 15
Seal Kit Replacement ................................................................................................................................ 16
Cog Brake and Side Housing ..................................................................................................................... 17
Axle Shaft, Reduction Gears and Expansion Plate .................................................................................... 18
Motor Shaft ................................................................................................................................................ 19
Input Shaft and Bypass Rod ...................................................................................................................... 20
Hydraulic Components .......................................................................................................................... 21-25
Transaxle Installation ................................................................................................................................. 25
Assembly After a Complete Teardown ........................................................................................................ 26
Sealant Application........................................................................................................... 27
Parts List ..................................................................................................................... 28, 29
Glossary of Terms ...................................................................................................... 30, 31
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FOREWORD
Headquartered in Sullivan, Illinois, Hydro-Gear
is a world leader in the design, manufacture,
and service of quality hydrostatic transaxles for
the lawn and garden industry. The mission of
our company is to be recognized by our customers and the industry as a world-class supplier and the quality leader in everything we do.
This Service and Repair Manual is designed to
provide information useful in servicing and
troubleshooting the Hydro-Gear 310-2200 EZT
Integrated Zero-Turn Transaxle.
Also included is a glossary of terms that are
frequently used throughout the industry and in
Hydro-Gear service publications. Understanding terminology is very important!
It is necessary, and a good shop practice, that
your service area be equipped with the proper
tools and the mechanics be supplied the latest
information available. All repair procedures illustrated in this guide are suggested, but preferred methods of repair.
®
Repair procedures require that the transaxle unit
be removed from the vehicle.
This is not a certification, test or study guide for
a certification test. If a technician is interested
in certification, they should contact an agent
representing the ESA (Engine Service Association) at (610) 363-3844 or their Hydro-Gear
Central Service Distributor. Many distributors will
be hosting certification testing. These study
®
guides will cover most of the products and manufacturers in our industry.
For more information about Hydro-Gear or our
products, please contact your Central Service
Distributor, or call our Customer Service Department at (217) 728-2581.
310-2200 EZT
®
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
SECTION 1. DESCRIPTION AND OPERATION
INTRODUCTION
The purpose of this manual is to provide information useful in servicing the Hydro-Gear® Inte-
®
grated Zero-Turn Transaxle (EZT
includes the EZT’s general descriptions, hydraulic schematics, technical specifications, servicing and troubleshooting procedures.
The transaxle normally will not require servicing
during the life of the vehicle in which it is installed. Should other servicing be required, the
exterior of the transaxle will need to be thoroughly cleaned before beginning most procedures. Do not wash the transaxle while it is hot.
Do not use a pressure washer to clean the unit.
). This manual
GENERAL DESCRIPTION
The 310-2200 is a self contained unit designed
for the transfer and control of power. It provides
an infinitely variable speed range between zero
and maximum in both forward and reverse
modes of operation.
pump and thus reverses the direction of the motor output rotation. The pump and motor are of
the axial piston design and utilize spherical nosed
pistons which are held against a thrust race by
internal compression springs.
The 310-2200 has a self contained fluid supply
and an internal filter. The fluid is forced through
the filter by a positive “head” on the fluid in the
housing/expansion tank with an assist by the
negative pressure created in the pump pistons
as they operate.
The check valves in the center section are used
to control the make-up flow of the fluid to the
low pressure side of the loop.
A cam style, block lifting bypass is utilized in the
310-2200 to permit moving the vehicle for a short
distance at a maximum of 2 m.p.h. (3.2 Km/h)
without starting the engine.
WARNING
This transaxle uses a variable displacement
pump with a maximum displacement of 10cc per
revolution, and motor with a fixed displacement
of 10cc per revolution. The variable displacement pump features a trunnion mounted
swashplate with a direct-proportional displacement control. Reversing the direction of the
swashplate reverses the flow of oil from the
Actuating the bypass will result in the loss
of hydrostatic braking capacity. The
machine must be stationary on a level
surface and in neutral when actuating the
bypass.
Figure 1. Hydraulic Schematic
2 310-2200 EZT
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
310-2200 EZT® HYDRAULIC FLOW SCHEMATIC
Figure 2. Hydraulic Flow Illustration
HYDRAULIC SCHEMATIC
Figure 2 provides an illustration of the hydraulic
oil circuit. The oil supply for the hydraulic system of the 310-2200 EZT® is also utilized for lubricating the components of the final drive assembly.
The input shaft and pump cylinder block are
turned in one direction only by the engine/drive
belt/pulley combination. Output of the oil flow is
controlled by the direction and amount that the
variable swashplate is angled. As the pump pistons compress they force the oil to flow through
one of two passageways (forward or reverse)
in the center section to the motor cylinder block
and motor shaft. Since the motor has a fixed
displacement angle it is forced to turn with the
flow of oil. As the angle of the pump swashplate
is increased the amount of oil being pumped will
increase and cause a higher speed output of the
motor. Reversing the angle of the pump
swashplate will reverse the direction of oil flow.
During the operation of the transaxle, fluid is
“lost” from the hydraulic loop through leak paths
designed into the product for lubrication purposes
(around pistons, under the rotating cylinder
blocks, etc.). This “lost” fluid returns to the
transaxle housing, then is pulled back into one
of the check valves depending upon the direction of vehicle operation. All of this oil must pass
through an internal filter.
The motor cylinder block mounts onto a splined
motor shaft which drives the gear train.
The bypass feature in the 310-2200 has a mechanical lever which lifts the motor block off of
the center section running surface. This allows
oil flow from the cylinder blocks to be discharged.
310-2200 EZT
®
3
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
EXTERNAL FEATURES 310-2200
4 310-2200 EZT
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
TECHNICAL SPECIFICATIONS
Technical specifications for the 310-2200 EZT® are listed in Table 1.
Table 1. Technical Specifications
Input Speeds Maximum Tire Diameter
Maximum: 3000 RPM 20 inch; 508 mm
Minimum: 1800 RPM
Weight of Unit Maximum Weight on Drive Tires
29.0 lbs. (13.15 Kg) 300 lbs. (136 Kg) with 20” Tires
340 lbs. (154 Kg) with 18” Tires
Table 2. 310-2200 EZT® Component Options
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:snoitpOdnEdnaretemaiDtfahSelxA
:noitacoLekarB
:epyTekarB
:noitacoLmrAlortnoC
:stnemegnarrAlortnoC
:noitcudeRelxasnarTllarevO
DD"4/3egnalF"1shtgnelsuoiravDD"1
draobnIdraobtuO
goCcsiDnoitcirF
draobnIdraobtuO
adnatS)elytsrossics(NTR
1:2.911:2.12
mrAlortnoCdr
PRODUCT IDENTIFICATION
The model and configuration of the 310-2200 EZT® can be determined from the label shown in Figure 3.
310-2200 EZT
Figure 3. Configuration Label
®
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
SECTION 2. SAFETY
This symbol points out important safety
instructions which, if not followed, could endanger the personal safety and/or property of yourself and others. Read and follow all instructions in this manual before attempting maintenance on your transaxle. When you see this
symbol - HEED ITS WARNING.
WARNING
POTENTIAL FOR SERIOUS INJURY
Inattention to proper safety, operation, or
maintenance procedures could result in
personal injury, or damage to the equipment. Before servicing or repairing the
310-2200 EZT®, fully read and understand the safety precautions described
in this section.
Wear appropriate clothing. Loose or hanging
clothing or jewelry can be hazardous. Use the
appropriate safety equipment, such as eye and
hearing protection, and safety-toe and slip-proof
shoes.
Never use compressed air to clean debris from
yourself or your clothing.
TOOL SAFETY
Use the proper tools and equipment for the task.
Inspect each tool before use and replace any
tool that may be damaged or defective.
WORK AREA SAFETY
Keep the work area neat and orderly. Be sure
it is well lit, that extra tools are put away, trash
and refuse are in the proper containers, and dirt
or debris have been removed from the working
areas of the machine.
PERSONAL SAFETY
Certain safety precautions must be observed
while servicing or repairing the 310-2200 EZT®.
This section addresses some of these precautions but must not be considered an all-inclusive
source on safety information. This section is to
be used in conjunction with all other safety material which may apply, such as:
1) Other manuals pertaining to this machine,
2) Local and shop safety rules and codes,
3) Governmental safety laws and regulations.
Be sure that you know and understand the equipment and the hazards associated with it. Do not
place speed above safety.
Notify your supervisor whenever you feel there
is any hazard involving the equipment or the performance of your job.
Never allow untrained or unauthorized personnel to service or repair the equipment.
The floor should be clean and dry, and all extension cords or similar trip hazards should be removed.
SERVICING SAFETY
Certain procedures may require the vehicle to
be disabled in order to prevent possible injury
to the servicing technician and/or bystanders.
The loss of hydrostatic drive line power may
result in the loss of hydrostatic braking capability.
Some cleaning solvents are flammable. Use only
approved cleaning materials: Do not use explosive or flammable liquids to clean the equipment.
To avoid possible fire, do not use cleaning solvents in an area where a source of ignition may
be present.
Discard used cleaning material in the appropriate containers.
6 310-2200 EZT
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
SECTION 3. TROUBLESHOOTING
WARNING
Do not attempt any servicing or adjustments with the engine running.
Use extreme caution while inspecting the
drive belt assembly and all vehicle linkage!
not related to a defective transaxle, but are
caused by slipping drive belts, partially engaged
bypass valves, and loose or damaged control
linkages. Be sure to perform all operational
checks and adjustments outlined in Section 4,
Service and Maintenance, before assuming the
pump is malfunctioning. Table 3 below provides
In many cases, problems with the 310-2200 are
Follow all safety procedures outlined in
the vehicle owner’s manual.
Table 3. 310-2200 EZT® Troubleshooting Checklist
a troubleshooting checklist to help determine the
cause of operational problems.
Possible Cause Corrective Action
UNIT OPERATES IN ONE DIRECTION ONLY
Control linkage bent or out of adjustment Repair or replace linkage, Page 8
Drive belt slipping or pulley damaged Repair or replace drive belt or pulley, Page 8
VEHICLE DOES NOT DRIVE/TRACK STRAIGHT
Vehicle tires improperly inflated Refer to vehicle manufacturer suggested pressure
Control linkage bent or out of adjustment Repair or replace linkage, Pages 8 and 11
Bypass assembly sticking Repair or replace bypass, Page 20
UNIT IS NOISY
Oil level low or contaminated oil Fill to proper level or change oil, Page 9
Excessive loading Reduce vehicle loading, Page 8
Loose parts Repair or replace loose parts
Bypass assembly sticking Repair or replace linkage
Air trapped in hydraulic system Purge hydraulic system, Page 10
UNIT HAS NO/LOW POWER
Engine speed low Adjust to correct setting
Control linkage bent or out of adjustment Repair or replace linkage, Page 8
Drive belt slipping or pulley damaged Repair or replace drive belt or pulley, Page 8
Oil level low or contaminated oil Fill to proper level or change oil, Page 9
Excessive loading Reduce vehicle loading, Page 8
Bypass assembly sticking Repair or replace linkage
Air trapped in hydraulic system Purge hydraulic system, Page 10
UNIT IS OPERATING HOT
Debris buildup around transaxle Clean off debris, Page 8
Cooling fan damaged Repair or replace cooling fan
Oil level low or contaminated oil Fill to proper level or change oil, Page 9
Excessive loading Reduce vehicle loading, Page 8
Air trapped in hydraulic system Purge hydraulic system, Page 10
TRANSAXLE LEAKS OIL
Damaged seals, housing, or gaskets Replace damaged component
Air trapped in hydraulic system Purge hydraulic system, Page 10
310-2200 EZT
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
SECTION 4. SERVICE AND MAINTENANCE
NOTE: Any servicing dealer attempting
a warranty repair must have prior approval before conducting maintenance of
a Hydro-Gear® product unless the servicing dealer is a current Authorized HydroGear Service Center.
EXTERNAL MAINTENANCE
Regular external maintenance of the 310-2200
®
EZT
should include the following:
1. Check the vehicle operator’s manual for
the recommended load ratings. Insure
that the current application does not exceed load rating.
2. Check oil level in accordance with Figure 4
Page 9.
3. Inspect the vehicle drive belt, idler pulley(s),
and idler spring(s). Insure that no belt slippage can occur. Slippage can cause low input speed to the transmission.
4. Inspect the vehicle control linkage to the directional control arm on the transaxle. Also
insure that the control arm is securely fastened to the trunnion arm of the transaxle.
FLUIDS
The fluids used in Hydro-Gear products have been
carefully selected, and only equivalent, or better
products should be substituted.
Typically, an engine oil with a minimum rating of
9.0 cSt (55 SUS) at 230° F (110° C) and an API
classification of SL is recommended. A 20W50
engine oil has been selected for use by the factory and is recommended for normal operating
procedures.
FLUID VOLUME AND LEVEL
Fluid volume information is provided in Table 4.
Certain situations may require additional fluid to
be added or even replaced. Refer to Page 4
and Figure 4 for the proper fill port location.
Fill the 310-2200 so the oil level is .75”-1.50”
(19-38 mm) below the oil fill port.
Recheck the fluid level once the unit has been
operated for approximately 1 minute.
Purging will be required. Refer to the purging
procedures on Page 10.
5. Inspect the bypass mechanism on the
transaxle and the vehicle linkage to insure
that both actuate and release fully.
SERVICE AND MAINTENANCE
PROCEDURES
Some of the service procedures presented on
the following pages can be performed while the
310-2200 is mounted on the vehicle. Any repair
procedures as mentioned in the repair section
of this manual must be performed after the unit
has been removed from the vehicle.
8 310-2200 EZT
®
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FLUID CHANGE PROCEDURE
FLUID CHANGE
This transaxle is factory filled, sealed and does
not require oil maintenance. However, in the
event of oil contamination or degradation, oil
addition or change may alleviate certain performance problems.
1. Remove the transaxle from the vehicle.
2. Clean the oil fill port area of any debris.
3. Remove the oil fill port fitting.
4. Position the transaxle so the oil will drain
completely out of the housing.
Table 4. Fluid Volumes for the 310-2200 EZT
Fluid Description
20W50 engine oil
5. Fill the transaxle at the oil fill port according
to Figure 4.
6. Install the oil fill port fitting.
7. Purging will be required. Refer to the purging procedures on Page 10.
8. Recheck the fluid level once the unit has been
operated for approximately 1 minute.
®
Volume
54.1 fl.oz. (1600 ml) to 57.5 fl.oz. (1700 ml)
310-2200 EZT
Figure 4. Fluid Level and Fill Port
®
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PURGING PROCEDURES
Due to the effects air has on efficiency in hydrostatic drive applications, it is critical that it is
purged from the system.
These purge procedures should be implemented
any time a hydrostatic system has been opened
to facilitate maintenance or any additional oil
has been added to the system.
Air creates inefficiency because its compression and expansion rate is higher than that of
the oil approved for use in hydrostatic drive systems.
The resulting symptoms in hydrostatic systems
may be:
1. Noisy operation.
2. Lack of power or drive after short term operation.
3. High operation temperature and excessive
expansion of oil.
Before starting, make sure the transaxle/transmission is at the proper oil level. If it is not, fill to
the specifications outlined on Page 9, Figure 4.
The following procedures should be performed
with the vehicle drive wheels off the ground, then
repeated under normal operating conditions.
1. With the bypass valve open and the engine
running, slowly move the directional control
in both forward and reverse directions (5 or
6 times), as air is purged from the unit, the
oil level will drop.
2. With the bypass valve closed and the engine
running, slowly move the directional control
in both forward and reverse directions (5 to
6 times). Check the oil level, and add oil as
required after stopping the engine.
3. It may be necessary to repeat Steps 1 and
2 until all the air is completely purged from
the system. When the transaxle moves forward and reverse at normal speed purging
is complete.
10 310-2200 EZT
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RETURN TO NEUTRAL SETTING
WARNING
POTENTIAL FOR SERIOUS INJURY
Inattention to proper safety, operation, or
maintenance procedures could result in
personal injury, or damage to the equipment. Before servicing or repairing the
310-2200 EZT®, fully read and understand the safety precautions described
in this section.
The return to neutral mechanism on the transmission is designed to set the directional control into
a neutral position when the operator releases the
vehicle hand control. Follow the procedures below to properly adjust the return to neutral mechanism on the transaxle:
1. Confirm the transaxle is in the operating mode
(bypass disengaged). Raise the vehicle’s drive
tires off the ground to allow free rotation.
NOTE: It may be necessary to remove the
drive tire from the axle hub to access the linkage control and the transaxle return arm.
2. Remove the Original Equipment Manufacturer’s
(OEM’s) control linkage at the control arm. Refer
to Figure 5.
3. Start the engine and increase the throttle to
full engine speed.
WARNING
Do not attempt any servicing or adjustments with the engine running.
Use extreme caution while inspecting the
drive belt assembly and all vehicle linkage!
Follow all safety procedures outlined in
the vehicle owner’s manual.
4. Check for axle rotation. If the axle does not
rotate, go to Step 5. If the axle rotates, go to
Step 6.
5. Stop the vehicle’s engine. Reattach and ad-
just the OEM linkage according to Step 3 and
Step 4. Stop the vehicle engine. Refer to Figure
5.
6. Note the axle directional movement. Stop the
vehicle engine. Loosen the RTN adjustment
screw until the control arm can be rotated. Rotate the control arm in the opposite direction of
the wheel rotation in 5 degree increments.
Tighten the RTN adjustment screw. Refer to
table 6. Required Torque values, page 14. Recheck according to steps 3 and 4. Stop the vehicle engine. Reattach and adjust the OEM linkage according to the OEM manual. Recheck according to steps 3 and 4. Refer to Figure 5.
310-2200 EZT
RTN Adjustment Screw
Speed and Directional Control
Figure 5. Return to Neutral Setting (Model 618-04163)
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NOTES
12 310-2200 EZT
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
SECTION 5. REPAIR
HOW TO USE THIS MANUAL
Each subassembly illustrated in this section is
illustrated with an exploded view showing the
parts involved. The item reference numbers
in each illustration are for assembly instructions only. See page 29 for part names and de-
scriptions. A complete exploded view and item
list of the transaxle is provided at the end of the
repair section.
GENERAL INSTRUCTIONS
Cleanliness is a primary means of assuring
satisfactory life on repaired units. Thoroughly
clean all exposed surfaces prior to any type of
maintenance. Cleaning of all parts by using a
solvent wash and air drying is usually adequate.
As with any precision equipment, all parts must
be kept free of foreign material and chemicals.
Protect all exposed sealing surfaces and open
cavities from damage and foreign material. The
external surfaces should be cleaned before
beginning any repairs.
Parts requiring replacement must be replaced
from the appropriate kits identified in the Items
Listing, found at the end of this manual. Use
®
only original Hydro-Gear
found in BLN-51427 (CD).
IMPORTANT: When internal repair is performed
on the 310-2200 EZT®, the filter assembly must
be replaced.
replacement parts
TRANSAXLE REMOVAL
It is necessary to remove the 310-2200 from
the vehicle before performing the repair procedures presented in this section.
LIMITED DISASSEMBLY
The following procedures are presented in the
order in which they must be performed to completely disassemble the unit. Do not disassemble
the unit any farther than is necessary to accomplish the required repairs. Each disassembly procedure is followed by a corresponding assembly procedure.
Upon removal, it is recommended that all seals,
O-rings, and gaskets be replaced. During installation lightly lubricate all seals, O-rings and
gaskets with a clean petroleum jelly prior to
assembly. Also protect the inner diameter of
seals by covering the shaft with a cellophane
(plastic wrap, etc.) material.
Reassembly is accomplished by performing the
“Assembly” portions of the procedures. If the
unit has been completely disassembled, a summary of the assembly procedures, in the order
in which they should occur, is given on page 24.
310-2200 EZT
®
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TOOLS AND TORQUES
Table 5. Required Tools
Miscellaneous
310-2200 Service & Repair Manual
Flat Blade Screw Driver (2)
Torque Wrench
Air Impact Wrench
Rubber Mallet
Breaker Bar
Side Cutters/Snips
Pliers
Needle Nose
Large External Snap Ring
Small Internal Snap Ring
Table 6. Required Torque Values
Sockets
1/2”-3/8” Adapter
3/8” Deep
1/2” Deep
7/16” Deep
9/16” Deep
3/4” Deep
13/16” Deep
7/8”
T-25 Torx Head
T-40 Torx Head
Apex AN-08
Operation Torque Item Description
Side Housing Screws 135-185 lb-in [15-21 Nm] 9 Screw 1/4-20 x 1.25
Control Arm Screw 230-310 lb-in [26-35 Nm] 25 Screw 5/16-24 x 1
Control Arm Stop Stud 50-120 lb-in [6-18 Nm] 21 Stud 5/16-24
Center Section Bolts 525-700 lb-in [60-80 Nm] 12 Screw 3/8-24 x 2.5
Check Plugs 200-360 lb-in [23-41 Nm] 56 Check Plug Assembly
Expansion Plate Screws 25-50 lb-in [3-6 Nm] 53 Screw 10-32 x 0.50
Fan/Pulley Lock Nut 360-520 lb-in [41-59 Nm] 122 Lock Nut 1/2 x 20
Cog Brake Bolt 80-120 lb-in [9-14 Nm] 55 Bolt 1/4-20 x 1
RTN Adjustment Screw 85-120 lb-in [10-14 Nm] 131 Screw 5/16-24 x 1.00
Hub Nut 100-160 lb-ft [136-217 Nm] 99 Nut, Hex 3/4-16 Lock
14 310-2200 EZT
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CONTROL ARM AND BYPASS ARM
Refer to Figure 6.
Disassembly
1. Loosen and remove the lock nut (26) and flat
washer (24). Discard the lock nut (26) and
flat washer (24).
2. Remove the torx head screw (25) from the
directional control.
3. Remove control arm (23) and pucks (22).
Discard the pucks.
4. Remove the bypass arm retaining ring (18)
and bypass arm (17). Discard the retaining
ring.
5. If necessary, remove and replace the control arm stop stud (21).
Inspection
Assembly
1. Install the bypass arm (17) onto the bypass
rod. Secure the bypass arm with a new retaining ring (18).
2. Replace the control arm stop stud (21) if
removed. Torque according to specifications
in Table 6 on page 14.
3. Install the control arm (23).
4. Install the control arm screw (25). Refer to
Table 6 for screw torque specifications.
1. Inspect the control arm stop stud (21) for
wear or damage.
2. Inspect the control arm (23) for wear or damage.
3. Inspect the bypass arm (17) for wear or damage.
310-2200 EZT
Figure 6. Control Arm and Bypass Arm
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SEAL KIT REPLACEMENT
Before disassembly, wipe the unit free of any
debris to avoid contamination.
Refer to Figure 7.
Input Seal
1. Remove the input pulley from the input shaft.
2. Remove the seal retaining ring (34).
3. Carefully pull the input seal (33) out of the
housing bore with a “hook” type tool. Care
must be taken to avoid damage to the housing bore or shaft sealing area.
4. Lubricate the new seal with petroleum jelly
prior to installation.
5. Wrap the shaft keyway (splines) with cellophane to prevent damage to the seal lip during installation.
6. Slide the seal over the shaft and press it into
the housing bore.
Trunnion Seal
1. Remove the control arm and any attachments
to the control arm. See page 15.
2. The seal (20) can be replaced by following
steps 3-6 of the procedure used to replace
the input shaft.
Bypass Seal
1. Remove the bypass arm and any attachments to the bypass arm. See page 15.
2. Remove the seal retaining ring (16). Remove
the bypass rod, keeping the retaining ring
(14) attached. Remove the bypass rod seal
(13). Deburr the bypass rod.
3. Install the seal (13). Install the bypass rod
with the retaining ring (14) attached. Install
the seal retaining ring (16).
7. The seal should seat against the spacer.
8. Install the seal retaining ring (34) and make
sure it is fully seated in its groove.
Output Seal
1. The seal (51) can be replaced by following
steps 2-6 of the procedure used to replace
the input seal.
2. Install the retaining ring (34) and make sure
it is fully seated in its groove.
Motor Shaft Seal
1. Remove the cog brake. See page 17.
2. The seal (10) can be replaced by following
steps 3-6 of the procedure used to replace
the input shaft.
Figure 7. Seal Kit Replacement
16 310-2200 EZT
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Page 19
Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
COG BRAKE AND SIDE HOUSING
Refer to Figure 8.
Disassembly
1. Remove the control arm and bypass arm. See
page 15.
2. Remove the oil from the transaxle. See page
9.
3. Remove the brake arm assembly (55), retaining ring (14) and cog brake disc (100).
4. Remove the lip seal (10).
5. Remove the housing screws (9).
6. Pull the side housing (2), leaving the axle
(49) and bull gear (46) assembled in the main
housing. It may be necessary to use screwdrivers at the pry points to break loose the
sealant (positions H-L and M-P, Figure 8).
7. Clean off
main housings. Take care not to damage the
sealing surfaces. A wire brush and solvent is
effective.
all the old sealant on the side and
Inspection
1. Check the brake arm brake disc for excessive wear or teeth damage. Replace if necessary.
2. Check for excessive looseness at the arm
pivot point.
3. Inspect the bearing and bushing areas in the
side housing.
Assembly
1. Apply a bead of sealant around the perimeter of the side housing face. See sealant
pattern on page 27.
2. Install the locating pins (8), if not already installed.
3. Install the side housing (2). Use care not to
smear the sealant bead.
4. Install the side housing screws (9). Refer to
the screw tightening pattern in Figure 8 and
torque specification in Table 6 on page 14.
5. Install the remaining seals. Refer to page 16.
Remember to use a seal protector during installation.
6. Install the brake disc (100), retaining ring
(14) and brake arm assembly (55).
7. Fill the transaxle with new oil. See page 9.
8. Install the bypass arm and control arm. See
page 15.
310-2200 EZT
Figure 8. Cog Brake and Side Housing Assembly
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
AXLE SHAFT, REDUCTION GEARS AND EXPANSION PLATE
Refer to Figure 9.
Disassembly
1. Remove the bypass arm and control arm. See
page 15.
2. Remove oil from the transaxle. See page 9.
3. Remove the side housing. See page 17.
4. Remove the spiral retaining ring (45), bull
gear (46), inboard sleeve bearing (48) and
washer (47).
5. Remove the reduction gears (42 &43), jack
shaft pin (44) and washers (41).
6. Remove seal retaining ring (34), seal (51),
axle (49) and bushing (50).
7. If necessary, remove the expansion plate assembly (53).
NOTE: Expansion plate removal will typically
destroy the plate. Clean all sealant from the
expansion plate area.
Inspection
1. Inspect the bull gear for wear or damage.
2. Inspect the reduction gears, jack shaft pin
and washers.
3. Inspect the axle shaft, bearing and bushing.
4. Inspect the expansion plate.
Assembly
1. Apply a small bead of sealant to the expansion plate area of the housing. See page 27.
Install the expansion plate (53). Torque the
screws according to Table 6.
2. Reassemble and install the reduction gears
(42 & 43), jack shaft pin (44) and washers
(41).
3. Install the bull gear (46), retaining ring (45),
bearing (48) and washer (47) onto the axle
(49).
4. Install the axle (49) and bushing (50) into the
housing (1).
5. Install the axle seal (51) and retaining ring
(34).
6. Install the side housing. See page 17.
7. Install all remaining seals. See page 16.
8. Fill the transaxle with oil. See page 9.
9. Install the bypass arm and control arm. See
page 15.
Figure 9. Axle Shaft, Reduction Gears and Expansion Plate
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
MOTOR SHAFT
Refer to Figure 10.
Disassembly
1. Remove the control arm and bypass arm. See
page 15.
2. Drain the oil from the transaxle. See page 9.
3. Remove the side housing. See page 17.
4. Remove the reduction gears. See page 18.
5. Remove flat washer (36), motor shaft and pinion gear (39 & 38) and flat washer (40).
Inspection
1. Inspect the motor shaft (39), pinnion gear (38)
and flat washers (36 & 40) for wear or damage.
Assembly
1. Insert the motor shaft (39) with the pinnion
gear (38) and flat washers (36 & 40) into the
center section (57).
2. Install the reduction gears. See page 18.
3. Install the side housing. Refer to page 17.
4. Install new seals. Refer to page 16.
5. Fill the transaxle with oil. See page 9.
6. Install the bypass arm and control arm. See
page 15.
310-2200 EZT
Figure 10. Motor Shaft
®
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
INPUT SHAFT AND BYPASS ROD
Refer to Figure 11.
Disassembly
1. Remove the control arm and bypass arm. See
page 15.
2. Drain the oil from the transaxle. See page 9.
3. Remove the side housing. See page 17.
4. Remove the reduction gears. See page 18.
5. Remove the motor shaft. See page 17.
6. Remove the retaining ring (34) and shaft seal
(33). Discard the seal.
7. Remove the spacer (32) and input shaft assembly (29, 30 & 31).
8. Remove the compression spring (27) and
washer (28).
5. Deburr the end of the bypass rod. Install the
bypass rod (15), retaining ring (14), seal (13)
and retaining ring (16).
6. Install the motor shaft. See page 19.
7. Install the reduction gears. See page 18.
8. Install the side housing. See page 17.
9. Install new seals in the side housing. See
page 16.
10.Fill the transaxle with oil. See page 9.
11.Install the bypass arm and control arm. See
page 15.
9. Remove the rings (14 & 16), bypass rod (15)
and seal (13).
Inspection
1. Inspect the input shaft components and bypass rod for wear or damage.
Assembly
1. Visually ensure that the pump block is aligned
concentrically with the center section running face.
2. Install the compression spring (27) and
washer (28).
3. Insert the input shaft (29), with bearing (30)
and retaining ring (31), into the pump block
assembly. NOTE: Do not force the shaft
and bearing as damage may occur. If alignment is correct, the shaft assembly will fit
into place.
4. Install the washer (32), seal (33) and retaining ring (34). Use a seal protector when installing the input shaft seal.
20 310-2200 EZT
Figure 11. Input Shaft and Bypass Rod Assembly
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Page 23
Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
HYDRAULIC COMPONENTS
Refer to Figures 12-21.
Disassembly
1. Remove the bypass arm and control arm. See
page 15.
2. Drain the oil from the transaxle. See page 9.
3. Remove the side housing. See page 17.
4. Remove the reduction gears. See page 18.
5. Remove the motor shaft. See page 19.
6. Remove the input shaft and bypass rod. See
page 20.
7. (See Figure 12) Remove the swashplate
(19) and pump cylinder block (4) as one assembly. NOTE: Removal will be aided by applying a small amount of pressure on the trunnion mounted swashplate towards the center section. Also note that the control arm (23,
page 28) may be loosely assembled at this
point to assist in swashplate removal. While
gently removing the swashplate and block
assembly, keep the block face flush with the
center section to minimize damage to the
running surface.
(Center Section/Filter)
12.(See Figure 16) Remove the center section
mounting screws (12). NOTE: The center
section is under motor block piston spring
pressure. These screws are factory installed
to 700 lb-in (80 Nm) and use an anaerobic
thread adhesive. A breaker bar will be required at this step. Clean the internal threads
of the mounting holes with compressed air.
13.Remove the center section and filter assembly (57, Figure 17). NOTE: Bypass plate (Figure 17) may slide out of the center section.
14.Remove the filter cover by pressing in and
down on the filter cover tabs. Discard the
cover.
15.Note the location of both check plugs (56)
before removal for correct replacement during reassembly. Remove and inspect the
check plug assemblies (56) for debris or
damage.
16.Remove the filter base (61) and discard it.
NOTE: The filter base is included in the filter
kit to be installed during reassembly of the
unit.
8. (See Figure 13) Disassemble the pump cyl-
inder block (4) from the swashplate (19).
9. (See Figure 14) Check each piston for
proper operation by pressing the pistons in
and releasing them in the block bore. Disassemble the pump cylinder block. Check for
piston/block wear in the cylinder bore. Inspect
the pistons (A), piston springs (C) and thrust
washers (B) for excessive wear or damage.
NOTE: Thrust washers may be held in place
in the piston by residual oil.
10.Reassemble the pistons, springs and washers into the cylinder block and set aside.
11. (See Figure 15) Remove the thrust bearing
assembly (35) from the swashplate (19).
310-2200 EZT
®
(Motor Block)
17.(See Figure 19) Remove the motor cylinder
block assembly (4) from the housing (1).
18.Disassemble the motor cylinder block assembly (4). Check each piston for proper
operation by pressing the pistons in and releasing them in the block bore. Disassemble
the motor cylinder block. Check for piston/
block wear in the cylinder bore. Inspect the
pistons, piston springs and thrust washers
for excessive wear or damage. NOTE:
Thrust washers may be held in place in the
piston by residual oil.
19.Reassemble the pistons, springs and thrust
washers into the cylinder block and set aside.
21
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
20.Remove the thrust bearing assembly (35)
from the housing (1). Inspect the thrust bearing and thrust bearing cavity in the housing.
Inspection
1. Inspect the pump cylinder block running surface for wear or damage.
2. Inspect the swashplate and thrust bearing
assemblies for wear or damage.
3. Inspect the center section block running surfaces. NOTE: These “sealing” surfaces
should be smooth in appearance without
scratches, scoring, nicks or abrasions. Drag
a fingernail across the surface to detect uneven wear or scratches which may not be
visible.
4. Inspect the threaded check plug ports of the
center section for debris or damage.
5. Inspect the motor cylinder block running surface for damage and wear.
6. Inspect all bearing, bushing and wear areas
in the housing.
Assembly
(Motor Block)
(Center Section/Filter)
3. (See Figure 18) Install the new filter base (61)
onto the center section (57).
4. It will be necessary to clean the check plugs
prior to re-assembly. Install the check plugs
(56), in their correct location, into the center
section (57). Tighten the check plugs according to Table 6.
5. Align the tabs on the filter cover with the
slots in the filter base and carfully press the
cover onto the base until the tabs snap into
place. Insure the bypass plate (Figure 18) is
located properly in the center section.
6. (See Figures 10 & 20) Install the motor shaft
(39), pinion gear (38) and flat washers (36 &
40) into the center section (57).
7. Assemble the motor block assembly (4) onto
the motor shaft (39).
8. (See Figure 20) Install the motor shaft, center section and motor block assembly into the
housing so that the motor block pistons contact the thrust bearing race. NOTE: Hold in
place and insure all pistons are still positioned
correctly in the cylinder bore by confirming
spring bias against the center section.
1. (See Figure 19) Turn the housing (1) so the
motor thrust bearing cavity is facing up. This
will assist in the installation of the motor
thrust bearing assembly (35) keeping it in
the bearing cavity during installation of the
center section assembly (57, Figure 17).
2. Insert the thrust bearing (35) in the housing
(1). NOTE: Place the thin race of the bearing towards the housing bearing cavity. The
thick race must face the pistons.
22 310-2200 EZT
9. (See Figure 16) After applying thread adhe-
sive, insert the center section mounting
screws (12) while holding downward pressure on the center section assembly (57,
Figure 20).
10.Tighten the center section mounting screws
(12) to the proper torque. Refer to Table 6.
NOTE: The center section must be fully
seated into the pilot bore before the screws
are tightened. The center section will not self
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Page 25
Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
locate.
(Swashplate/Pump Block)
11. (See Figure 15) Install the pump thrust bear-
ing (35) in the trunnion machined swashplate
(19). NOTE: Place the thin race of the bearing towards the swashplate. The thick race
must face the pistons.
12.(See Figure 13) Place the pump block as-
sembly (4), pistons down, on top of the thrust
bearing in the swashplate (19).
13.Coat the pump running surface with clean
motor oil.
14.Care must be taken to prevent the scaring
or scratching of the center section sealing
face during this step. Insert the shaft of the
swashplate/pump block assembly (Figure
21) into the housing while simultaneously
compressing the pistons in the block. NOTE:
To assist in the installation of these components, insert the assembly until 3/4 of the
pump block is covered by the center section.
Then slightly press the shaft end toward the
center section while pushing the shaft into
its bore.
15.Install the input shaft and bypass rod. See
page 20.
16. Install the axle shaft, reduction gears and expansion plate, if removed. Refer to page 18.
17. Install the side housing and brake. See page
17.
Figure 12.
Figure 13.
18.Fill the transaxle with new oil. See page 9.
19.Install the bypass arm and control arm. See
page 15.
310-2200 EZT
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Figure 14.
23
Page 26
Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
Figure 15.
Figure 16.
Figure 18.
Figure 19.
Figure 17.
24 310-2200 EZT
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Page 27
Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
TRANSAXLE INSTALLATION
Use the following procedure to complete the
installation of the transaxle on the vehicle.
1. Install and secure the transaxle on the
vehicle according to the instructions in the
vehicle owner’s manual.
2. With the vehicle raised, install the wheels
on the axles, and snug the wheel hardware.
3. Lower the vehicle wheels to the ground
and torque the wheel hardware per the
vehicle owner’s manual.
Figure 20.
Figure 21.
310-2200 EZT
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
ASSEMBLY AFTER A COMPLETE TEARDOWN
If the unit has been torn down completely, the
following summary identifies the assembly
procedures necessary to completely assemble the unit. Each assembly procedure is
located by a page reference.
The part reference numbers provided in each
assembly procedure are keyed to the individual exploded views, and are also keyed to
the complete unit exploded view on page 26.
1. Install the hydraulic components. See
pages 21-25.
2. Install the input shaft and bypass rod. See
page 20.
3. Install the axle shaft, reduction gears and
expansion plate. See page 18.
4. Install the cog brake and side housing.
See page 17.
5. Fill the transaxle with new oil. See page 9.
6. Install the bypass arm and control arm.
See page 15.
7. Install the transaxle onto the vehicle.
8. Perform the purge procedures listed on
page 10.
26 310-2200 EZT
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Page 29
Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
NOTE: Prior to applying the new sealant, the
old sealant must be removed from all surfaces.
A small consistent bead of the sealant around
the housing face will be sufficient.
ingly.
The illustration below indicates the correct
areas.
Use spar-
SEALANT APPLICATION
310-2200 EZT
®
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
310-2200 EXPLODED VIEW
NOTES:
1. BRAKE AND CONTROL ARM CAN BE ON EITHER SIDE.
2. LH SIDE SHOWN. RH SIDE IS A MIRROR IMAGE.
ITEMS NOT SHOWN
11 - OIL, 20W50
58 - SEALANT TUBE (10.3 oz)
52 - KIT, SEAL
145 - ASSEMBLY, HUB PULLER
Figure 22. 310-2200
28 310-2200 EZT
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Page 31
Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
310-2200 ITEMS LIST
No. DESCRIPTION No. DESCRIPTION
1 ASSEMBLY, MAIN HOUSING 47 WASHER, 3/4 ID X 1-1/2 OD X .13
HOUSING, MAIN 48 BEARING, SLEEVE (INBOARD)
BUSHING, .865 X .985 X.790 49 AXLE
PLATE, EXPANSION 50 BUSHING, .752 X 1.571 X .625
SCREW, 10-32 X 1/2 (SELF TAPPING) 51 SEAL, LIP .750 X 1.577 X .250
PIN, STANDARD, HEADLESS 52 KIT, SEAL
SEAL, LIP .375 X .75 X .25 53 KIT, EXPANSION PLATE
2 ASSEMBLY, SIDE PLATE EXPANSION
HOUSING, SIDE SCREW, 10-32 X 1/2 (SELF-TAPPING)
BUSHING, .624 X .719 X .562 54 KIT, FAN-PULLEY
BUSHING, .865 X .985 X .790 55 KIT, BRAKE ARM
3 PLATE, BYPASS ARM, PARKING BRAKE
4 ASSEMBLY, PUMP BLOCK WASHER .28 X .50 X .063
BLOCK, CYLINDER BOLT, 1/4-20 X 1 W/PATCH
PISTON BUSHING, .260 X .394 X .330
SPRING, COMPRESSION PIN, CLEVIS
WASHER, THRUST 56 CHECK PLUGS
5 SPACER 57 KIT, CENTER SECTION-FILTER
6 ASSEMBLY, MOTOR BLOCK CENTER SECTION, MACHINED
7 PLUG, 9/16-18 BUSHING, .707 X .788 X .591
8 PIN, STAINLESS, HEADLESS PLATE, BYPASS
9 HFHCS 1/4-20 X 1.25 (SELF-TAPPING) BOLT, HEX FLANGE 3/8-24 X 2.5
10 SEAL, LIP .625 X 1.000 X .250 FILTER, BASE
12 BOLT, HEX FLANGE 3/8-24 X 2.5 CHECK PLUG ASSEMBLY
13 SEAL, LIP .375 X .75 X .25 ASSEMBLY, COVER
14 RING, RETAINING .375 EXT ASSEMBLY, PUMP BLOCK
15 ROD, BYPASS 59 KIT, BYPASS ARM
16 RING, RETAINING .750 INT ARM, BYPASS
17 ARM, BYPASS RING, RETAINING .375 EX T (PUSHNUT)
18 RING, RETAINING .375 EXT (PUSHNUT) 61 KIT, FILTER
19 SWASHPLATE, TRUNNION, MACHINED FILTER, BASE
20 SEAL, LIP 18 X 32 X 7 ASSEMBLY, COVER
21 STUD 99 NUT, HEX 3/4-16 LOCK
22 PUCK, FRICTION 100 DISC, COG BRAKE
23 ARM, CONTROL 120 FAN, 10 BLADE
24 WASHER, FLAT 11/32 ID X 7/8 OD X 1/16 121 PULLEY
25 TWHCS 5/16-24 X 1.0 122 HEX LOCK NUT, 1/2-20 (NYLON INSERT)
26 NUT, HEX LOCK 5/16-24 UNJF 123 WASHER, OD SLOTTED
27 SPRING-HELICAL COMPRESSION HEX WASHER HEAD TAPPING SCREW 1/4-20 X .25
28 WASHER .591 X .787 X .040 124 ASSEMBLY, HUB, 4 STUD, 1/2-20 (30° TAPER)
29 SHAFT, INPUT 125 CAP, VENT ASSEMBLY
30 BEARING, BALL 17MM ID X 40MM OD X 12MM 126 FITTING, O-RING ASSEMBLY
31 RING, RETAINING WIRE .561 ID 127 CLAMP, PINCH, SINGLE EAR
32 SPACER 128 FITTING
33 SEAL, LIP 17 X 40 X 7 131 SHCS, 5/16-24 X 1.00 (PATCH)
34 RING, RETAINING 132 BUSHING, PILOT, 1.125
35 BEARING, THRUST 30 X 52 X 13 133 WASHER, PLASTIC
36 WASHER, FLAT 5/8 ID X 1.0 OD X .05 134 WASHER, 1.5 X .34 X .062
37 RING, RETAINING 135 SPRING, EXTENSION
38 GEAR, PINION, 13T 136 KIT, RTN ASSEMBLY
39 SHAFT, MOTOR 137 HOSE
40 WASHER, MOTOR SHAFT .71 ID X 1.16 OD X .04 138 KIT, BREATHER ASSEMBLY
41 WASHER, HT .5 ID X 1.0 OD X .032 140 PUCK, FRICTION
42 GEAR, 10T/48T 141 SPACER, FRICTION PUCK
43 GEAR, 10T JACKSHAFT 142 SPACER, .320 X .590 X .500
44 PIN, JACKSHAFT 143 SPRING, HELICAL COMPRESSION
45 RING, SPIRAL RETAINING 144 DEFLECTOR, BELT
46 GEAR, 52T BULL
310-2200 EZT
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
GLOSSARY OF TERMS
Axial Piston: Type of design for hydraulic motors and pumps in which the pistons are arranged
parallel with the spindle (input or output shaft).
Bantam Duty: A descriptive term relating to the product capacity (meaning: light duty).
Bypass Valve: A valve whose primary function is to open a path for the fluid to bypass the motor
or pump. Also referred to occasionally as the freewheel valve or dump valve.
Case Drain Line (Return Line): A line returning fluid from the component housing to the reservoir.
Cavitation: A concentrated gaseous condition within the fluid causing the rapid implosion of a
gaseous bubble.
Center Section: A device which acts as the valve body and manifold of the transmission.
Charge Pump: A device which supplies replenishing fluid to the fluid power system (closed loop).
Charge Pressure: The pressure at which replenishing fluid is forced into a fluid power system.
Charge Relief Valve: A pressure control valve whose primary function is to limit pressure in the
charge circuit.
Check Valve: A valve whose primary function is to restrict flow in one direction.
Closed Loop: A sealed and uninterrupted circulating path for fluid flow from the pump to the motor
and back.
Decay Rate: The ratio of pressure decay over time.
End Cap: See “Center Section”
Entrained Air: A mechanically generated mixture of air bubbles having a tendency to separate
from the liquid phase.
Gerotor: A positive displacement pump frequently used as a charge pump.
Hydraulic Motor: A device which converts hydraulic fluid power into mechanical force and motion
by transfer of flow under pressure.
Hydraulic Pump: A device which converts mechanical force and motion into hydraulic fluid power
by producing flow.
Hydrostatic Pump: See “Hydraulic Pump”
Hydrostatic Transaxle: A multicomponent assembly including a gear case and a hydrostatic
transmission.
30 310-2200 EZT
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
Hydrostatic Transmission: The combination of a hydraulic pump and motor in one housing to form
a device for the control and transfer of power.
Inlet Line: A supply line to the pump.
Integrated Zero-Turn Transaxle: The combination of a hydrostatic transmission and gear case in
one housing to form a complete transaxle.
Manifold: A conductor which provides multiple connection ports.
Neutral: Typically described as a condition in which fluid flow and system pressure is below that
which is required to turn the output shaft of the motor.
Pressure Decay: A falling pressure.
Priming: The filling of the charge circuit and closed loop of the fluid power system during start up,
frequently achieved by pressurizing the fluid in the inlet line.
Purging: The act of replacing air with fluid in a fluid power system by forcing fluid into all of the
components and allowing the air a path of escape.
Rated Flow: The maximum flow that the power supply system is capable of maintaining at a
specific operating pressure.
Scoring: Scratches in the direction of motion of mechanical parts caused by abrasive contaminants.
Swash Plate: A mechanical device used to control the displacement of the pump pistons in a fluid
power system.
System Charge Check Valve: A valve controlling the replenishing flow of fluid from a charge circuit
to the closed loop in a fluid power system.
System Pressure: The pressure which overcomes the total resistance in a system, including all
efficiency losses.
Valve: A device which controls fluid flow direction, pressure, or flow rate.
Variable Displacement Pump: A pump in which the displacement per revolution can be varied.
Volumetric Displacement: The volume for one revolution.
310-2200 EZT
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
NOTES
32 310-2200 EZT
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®
Page 35
Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
NOTES
310-2200 EZT
®
33
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Hydro Gear Parts or New Units Call 606-678-9623 or 606-561-4983
© 2008 Hydro-Gear
Rev. P2
Printed in U.S.A.
34 310-2200 EZT
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®
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