HOA HDX S120 Instruction Manual

HDX™ Cast Coupler
Installation & User Manual

© 2013 HOA Manufacturing Inc. Eugene, OR USA.
All rights reserved. Any use of the editorial or pictorial content of this publication is
strictly prohibited without express written permission from HOA Manufacturing Inc.
Printed in the USA (02/13). DCN HDX-IUM-01-20130216

TABLE OF CONTENTS
INTRODUCTION
Welcome & Contact Information....................................................... 1
Important Notes & Warranty Information .......................................... 2
GENERAL INFORMATION
Safety Messages & Recommendations............................................ 3-4
Part Identification Charts................................................................... 5-9
Hydraulic & Electrical Specifications................................................. 10
HDX™ Coupler Familiarization......................................................... 11-12
Recommended Welding Procedures................................................13
INSTALLATION INSTRUCTIONS
Installation Preparation ..................................................................... 14-15
Removing Attachment....................................................................... 16
Connecting Coupler to Excavator Arm.............................................. 17
Installing Hose Brackets ................................................................... 18-19
Hydraulic Hose Assembly................................................................. 20
Hydraulic Hose Routing.................................................................... 21-23
Control Valve, Filter & Switch Box.................................................... 24-28
OPERATION & MAINTENANCE
Warnings & Precautions ................................................................... 29-30
Switch Box Overview ........................................................................ 31
Engaging Attachment........................................................................ 32-35
Disengaging Attachment................................................................... 36
Lifting Loads with Coupler Installed.................................................. 37
Maintenance Procedures.................................................................. 38-39
Troubleshooting ................................................................................ 40
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HOA Manufacturing HDX™ Cast Coupler Installation & User Manual

Congratulations on your purchase of the HDX™ Cast Coupler. The HDX™ coupler is a high
quality, well-engineered product that will provide you with many years of excellent service.
The HDX™ coupler will deliver enhanced productivity of your excavator. This coupler brings
you the design, quality and workmanship you expect from a HOA Manufacturing product.
The advantages of the HDX™ coupler become apparent when a bucket or attachment
change is necessary. These advantages include:
 A locking mechanism with a locking lever that engages under and around the
attachment pin.
 A positive locking system, which pushes against the rear machine pin and away from
the front pin, keeps the coupler tight at all times.
 A check valve that helps to prevent the possibility of an accidental release of the
attachment.
 A lifting eye, which allows you to operate the machine as a lifting device without the
attachment, provides increased lifting power without bucket interference.
 A redundant locking spring that maintains positive pressure on the front lever.
The HDX™ coupler operates on the excavator’s low-pressure pilot system rather than the
main high-pressure system. Engaging an attachment is easier and safer using the low-
pressure pilot system. The attachment can remain on the ground and does not have to be
curled in to take the machine over relief. The HDX™ coupler is designed to allow the operator
to switch the attachments on a hydraulic excavator in a minimal amount of time.
The HDX™ coupler’s full potential will depend upon proper installation, operation, and
maintenance of the coupler and its systems. All users should read and understand this
manual and any accompanying materials thoroughly prior to installing, operating, or
maintaining your HDX™ coupler. Pay particular attention to your personal safety and
remember to follow all applicable standard safety precautions. If you have any questions or
concerns, contact your authorized HOA Manufacturing dealer.
Thank you for purchasing our product. We are confident you will be pleased with its
performance.
Mailing Address
HOA Manufacturing Inc.
PO Box 5134
Eugene, OR 97405
Physical Address
HOA Manufacturing Inc.
86360 Franklin Blvd C12 & 13
Eugene, OR 97405
HOA Manufacturing HDX™ Cast Coupler Installation & User Manual
1
Phone: [phone]

IMPORTANT NOTES
HOA Manufacturing builds hydraulic couplers to OEM attachment specifications. Our coupler is
designed to work only with attachments built to OEM attachment dimensions. The critical
dimensions are the pin-center to pin-center, stick width, and pin diameter dimensions. One should
properly ensure the attachments are built to these specifications before attempting to operate the
coupler. Additionally, one may encounter some attachments that have structural interferences
preventing the coupler from engaging the attachment. Any interference issues should be resolved
before operating the coupler. HOA Manufacturing assumes no responsibility or liability for
attachments not built to OEM specifications and/or that have structural interference problems. Any
costs incurred to modify attachments that do not conform to OEM specifications and/or have
structural interferences are solely the responsibility of the end user.
HOA MANUFACTURING WARRANTY POLICY AND PROCEDURES FOR COUPLERS
HOA Manufacturing warrants all couplers against defect in material and workmanship for a period
of one year or 1000 hours from the date of install, whichever comes first.
All warranty claims require submission of a PDI showing the original install date, as well as
machine hours at time of defect. This warranty does not apply to any coupler that has been
subjected to misapplication and/or abuse, or modified in any way without written authorization
from HOA Manufacturing. This warranty covers only new products manufactured by HOA
Manufacturing. Products manufactured by others are covered only by the warranties extended to
HOA Manufacturing by its suppliers.
Warranty claims must be made to HOA Manufacturing in advance of any repairs by submitting a
Warranty Claim Number and Warranty Claim Form, which can be obtained by contacting HOA
Manufacturing. Warranty claims made without a Warranty Claim Number will be rejected. Any
product returned to HOA Manufacturing for inspection or repair must be returned with freight
charges prepaid.
If HOA Manufacturing authorizes repairs be made by an outside source, HOA Manufacturing
reserves the right to determine and approve the time and rate charged for repairs. Repairs
completed by an outside source will be subject to warranty one time only. Subsequent failure of
repairs by an outside source is non-warrantable. HOA Manufacturing shall not be liable for down-
time by the customer, mileage costs, damaged equipment, or loss of productivity incurred by the
dealer or customer.
All products are wearable and expendable, and as such, HOA Manufacturing assumes no
responsibility for normal wear. It is the responsibility of the customer to follow normal maintenance
and operating procedures, including, but not limited to, daily inspection for routine hairline cracks.
Any cracks should be repaired to HOA Manufacturing specification before further damage occurs.
HOA Manufacturing specifically disclaims any and all warranties, expressed or implied, including,
but not limited to, any implied warranties of merchantability and fitness for any particular purpose
with respect to HOA Manufacturing products.
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HOA Manufacturing HDX™ Cast Coupler Installation & User Manual

This is the safety alert symbol. It is used to alert you of potential injury hazards. Observe
all safety messages that follow this symbol.
Safety messages in this manual are classified as follows:
DANGER Indicates an imminently hazardous situation that may result in death or
serious injury.
WARNING Indicates a potentially hazardous situation that may result in death or
serious injury.
CAUTION Indicates a potentially hazardous situation that may result in minor or
moderate injury and/or damage to the coupler or machine.
3
General Information
Safety Messages & Recommendations
To guard against death or injury, basic safety precautions should be observed before attempting to
install, operate, or maintain your HDX™ coupler.
Recommendations (Before You Begin)
Read this manual thoroughly before
attempting to install, operate, or maintain
your HDX™ coupler.
Before installing, unpack the coupler and
Coupler Installation Kit. Inspect the shipper’s
bill of lading and the Coupler Installation Kit
component list on pages 7-9, to ensure you
received all items. If items are missing,
contact your dealer.
Inspect all items for damage due to transit or
handling. If any items are damaged contact
your dealer.
Verify the coupler machine number on the
Serial Number ID Tag (Fig. 3-1) matches the
machine you are attempting to install the
coupler on.
Familiarize yourself with the coupler and
Coupler Installation Kit components before
installing, operating, or maintaining your
HDX™ coupler (see pages 5-12).
Sort your Coupler Installation Kit and group
components together by component type.
Be sure to group bolts with their respective
washers.
Fig. 3-1 (Coupler Serial Number ID Tag)
HOA Manufacturing HDX™ Cast Coupler Installation & User Manual

4
General Information
Safety Messages & Recommendations
DANGER
Failure to comply with information in this HOA Manufacturing HDX™ Cast Coupler User Manual may result in
injury, death, damage to property, and/or damage to the coupler. Ensure all personnel have read and
understand the information in this manual before attempting to install, maintain, and/or operate the HDX™
coupler.
WARNING
Read, understand, and follow all safety precautions and procedures found in the machine’s Operator Manual
before attempting any operation, inspection, or maintenance of your machine, its attachments, and/or
systems. HOA Manufacturing cannot anticipate every possible circumstance that might become a potential
hazard. The warnings in this document and on the product are therefore not all inclusive. If a tool, procedure,
work method, or operating technique not specifically recommended by HOA Manufacturing is used, you must
make certain for yourself it is safe for you and others. You should also ensure the product will not be
damaged or made unsafe by the operation, lubrication, maintenance and/or repair procedures you choose.
Other Recommendations
Install a Safe Operation decal on cab inside
right hand window near switch.
Always wear protective equipment during
installation, inspection, and maintenance
procedures.
Avoid oil spills. Ensure you have an ample
supply of rags and absorbent towels on
hand for cleaning purposes.
Dispose of all waste oils, fluids, lubricants,
and other hazardous waste properly.
Ensure all hoses, lines and fittings are clean,
open, and clear before connecting them to
the system.
Do not force any parts during assembly. If
the parts are properly aligned, the pins will
go in easily and the fittings will screw into
the valves without undue force.
Tighten all fittings securely and properly.
Lubricate all pins. Always use the original
machine pins, which came with the
excavator, to attach the coupler to the
excavator arm.
Route all hoses and wires in a neat and
orderly manner. Secure the hoses and wires
to other machine components.
All hoses should have enough slack to move
when powering the excavator arm or
attachment.
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5
Chart 1 – Excavator Parts
Chart 2 – Coupler/Attachment Parts
General Information
Part Identification Charts
This section provides diagrams for identification of the excavator, the coupler, and the Coupler
Installation Kit. These charts will also familiarize you with the terminology used in this manual.
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Chart 3 – HDX™ Coupler Parts (with Yoke)
General Information
Part Identification Charts
The HDX™ coupler is designed to pick up multiple pin diameters. Refer to this chart for the appropriate pin
diameter to match your HDX™ coupler.
HDX™ Coupler Model Pin Diameter
S120 60-65-70 mm
S200 70-80 mm
S250 80-90 mm
S350 90-100 mm
S450 100-110 mm
Chart 4 – HDX™ Coupler Pin Diameters
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7
General Information
Part Identification Charts
Chart 5 – Coupler Installation Kit Component List
Filter Components Part Number #6N-3 #6N-412 Drawing
Reference
Filter Head 1753144 1 1 A
Filter Element 20101 1 1 B
2” x 2” x 1/4” Angle Bracket MB-F 1 1 C
1/4” x 20” x 3/4” Hex Head Bolts with Washers 1/4 x 20 x 3/4 2 2 D
Switch Box Components Part Number #6N-3 #6N-412 Drawing
Reference
Buss 10 Amp Fuse FUSE10 1 1 E
3-Light Switch Box Assembly CCBX1020799-3 1 1 F
#8 x 1/2” Mounting Screws 8 x 1/2MS 3 3 G
Control Valve Components Part Number #6N-3 #6N-412 Drawing
Reference
Hydraulic Control Valve (24V Vickers) DG4V3S2CMU1H560 1 1 H
Mounting Sub Plate AD03SP-S6S 1 1 I
1/4” x 20” x 3/4” Sub Plate Mounting Bolts 1/4 x 20 x 3/4 SMB 2 2 J
1025 Mounting Screws BK-D03 4 4 K
Control Valve Wiring Harness HARNDIQD 1 1 L
Control Valve Mounting Bracket MB-V 1 1 M
Fittings & Hoses Part Number #6N-3 #6N-412 Drawing
Reference
#6 Reusable Female Hose Ends (Swivel) BL06-06NJ 18 18 N
#6 O-Ring x #6 JIC Male (90 Degree) 849FSO06X06 5 5 O
#8 O-Ring x #6 JIC Male 848FSO06X08 2 2 P
#6 JIC Male x #6 JIC Male (Straight Bulkhead Fitting) 2700-06-06 2 2 Q
#6 JIC Male x #6 JIC Male (45 Degree Bulkhead Fitting) 2702-06-06 2 2 R
Nut for Bulkhead Fittings 711BHSF06 4 4 S
#6 O-Ring x #6 JIC Male 6400-06-06 1 1 T
Upper & Lower Bulkhead Fittings Bracket #6MB 2 2 U
#6 2500 psi Single Braid Hydraulic Hose HFS06 125’ 150’ V
Protective Hose Sleeve NHS114 20 20 W
Wire Ties n/a 20 20 X
Tubular Hose Retainer Bracket n/a 1 1 Y
IMPORTANT
HOA Manufacturing makes every attempt to supply you with the appropriate fittings to install your coupler. However,
due to the variety of excavators, you will need to provide the specific fittings needed to tie into the pilot pressure
system and the hydraulic reservoir tank of your excavator. Contact your excavator dealer for the appropriate fittings.
In addition, if your machine requires adaptation of connectors, contact your excavator dealer.
HOA Manufacturing HDX™ Cast Coupler Installation & User Manual

L
Control Valve Wiring Harness
8
General Information
Part Identification Charts
The Coupler Installation Kit component drawings are not to scale and are for representation purposes
only.
A
Filter Head
B
Filter Element
C
2” x 2” x 1/4” Angle Bracket
1/4” x 20” x 3/4”
Hex Head Bolts w/ Washers
D F
3-Light Switch Box Assembly
E
Buss 10 Amp Fuse
G
#8 x 1/2” x Mounting Screws
H
Hydraulic Control Valve (24V Vickers)
I
Mounting Sub Plate 1/4” x 20” x 3/4”
Sub Plate Mounting Screws
J
M
Control Valve Mounting Bracket
K
1025 Mounting Screws
HOA Manufacturing HDX™ Cast Coupler Installation & User Manual

#6 O-Ring x #6 JIC Male
(90 Degree)
9
General Information
Part Identification Charts
The Coupler Installation Kit component drawings are not to scale and are for representation purposes
only.
#6 Reusable Female Hose Ends (Swivel)
N O P
#8 O-Ring x #6 JIC Male
Q
#6 JIC Male x #6 JIC Male
(Straight Bulkhead Fitting) #6 JIC Male x #6 JIC Male (45 Degree Bulkhead Fitting)
R S
Nut for Bulkhead Fittings
V
#6 2500 psi Single Braid Hydraulic Hose
X
Wire Ties
Y
Tubular Hose Retainer Bracket
T
#6 O-Ring x #6 JIC Male
Protective Hose Sleeve
W
Upper & Lower Bulkhead Fittings Brackets
U
HOA Manufacturing HDX™ Cast Coupler Installation & User Manual

10
General Information
Hydraulic & Electrical Specifications
This table provides the specifications for the hydraulic and electrical components of the Coupler
Installation Kit:
Hydraulic Filter Unit
Part Number Purolator 20101
Max Pressure 200 psi (13.8 bar)
Flow Rating 32 gpm (121L/min)
Temperature Range -45°F to 225°F (-43°C to 107°C)
Filter Cross Reference (other brands) Parker #921999, Baldwin #BT839-10 and Stauff #SF6620
Switch Box Assembly
Voltage Rating 24 VDC
Alarm Decibel Rating 72 dBA
Wiring Harness T4-2 SJT0W (TPE) 105°C FT2 water resistant
Hydraulic Control Valve
Part Number Vickers DG4V3S2CMU1H560
Power Rating 30W @ 24 VDC
Fatigue Pressure 5000 psi (350 bar)
System Pressure Excavator pilot pressure control system (Not to exceed 1000 psi)
Hydraulic Hose
#6 Single Braid Hose Eastman HFS06, 2500 psi (or equivalent)
#4 Single Braid Hose Eastman E7-04, 2750 psi (or equivalent)
CAUTION
Only use parts recommended by HOA Manufacturing
(or parts meeting the specifications above). Failure to
use parts recommended by HOA Manufacturing may
result in damage to the coupler and/or machine.
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11
General Information
HDX™ Coupler Familiarization
Springs
Constant pressure is maintained on the front lever
by two tension springs. These springs assist the
hydraulic cylinder by keeping the front lever
closed and secured.
Locking Rear Lever
The cast rear locking lever slides under the
attachment link pin in the rear mounting area of
the coupler. The sliding mechanism is designed to
minimize the chance of jamming. When the pin is
seated properly in the lever, pressure from the
hydraulic cylinder locks the attachment link pin
between the coupler frame and the sliding lever.
Because the locking system pushes away from
the front pin, the coupler remains tight, even as it
begins to wear.
Your HDX™ coupler is built with a low profile design. It is constructed from high strength steel casting. It
is built to accept OEM attachments, but is flexible enough to accept variances from these dimensions.
Review the following to familiarize yourself with the coupler components.
Front Lever
The HDX™ coupler features a cast front lever.
The geometry of the front lever, along with the
configuration and alignment of the other coupler
components, hold the front lever in the closed po-
sition without the assistance of the hydraulic cyl-
inder.
Lifting Eye
The cast lifting eye on your coupler is durable and
designed to handle the machine’s lifting capacity.
The excavator gains additional lifting capacity in
both weight and height when the coupler is used
to lift the load without the attachment. The closed
lifting eye should not be cut open or altered. An
approved lifting shackle is recommended for
attaching cables or other safety hoisting products.
Frame is one piece cast steel with
no structural welds, for long life.
( 1.5 times stronger than T1)
OEM Boss Design
Yoke
Cylinder
(see page 12)
Lifting Eye Springs
Locking Rear Lever
Multi-Pin Diameter
Front Lever
Multi-Pin Diameter
C-Casting
The C-casting fits two different pin diameters and
is FEA contoured for low stress.
C-Casting
HOA Manufacturing HDX™ Cast Coupler Installation & User Manual

12
General Information
HDX™ Coupler Familiarization
Cylinder Check Valve
The hydraulic cylinder features an external check
valve in the terminal block, on top of the cylinder.
This provides easy access and servicing of this
unit. Should a hose break, the check valve will
maintain constant pressure on the attachment link
pin. Once the attachment is engaged, the locking
lever can only be retracted by applying positive
pressure to the retract port. This is done by
placing the control box switch to the release
position.
Bleed Screw
The bleed screw is installed so you can bleed any
air that may be in the cylinder. This must be done
after the install, any time a hose is removed, as
well as, any time after the machine sits for any
length of time.
Cylinder check valve is a
cartridge type and separately
serviceable
Bleed Screw
Hydraulic ports are positional
for easy access
Hardened ball and socket
(spherical) self aligns and
requires no lubrication
Oversize solid chrome rod
Shafts are machined from a solid
block of steel, eliminating crack
prone welds
The cylinder is designed for maximum extension, giving more bucket compatibility. Additionally, it can be
used with yoke to give ultra long stroke capabilities. The double acting cylinder on the coupler is plumbed
for an external check valve. This feature locks the hydraulic pressure in the cylinder to prevent it from
backing away from the pin engagement.
HOA Manufacturing HDX™ Cast Coupler Installation & User Manual

When welding, always use proper welding protection and work in a well ventilated area.
Use an electrode or wire with a 70,000 lb tensile strength or higher. The cast frame can accommo-
date the use of 70,000-110,000 lb tensile strength. The higher the tensile strength, the stronger the
weld. However, the higher tensile strength is more difficult to weld. Preference should be given to
weld quality, rather than tensile strength.
Place the welding ground cable within three feet (one meter) of the area to be welded.
Ensure all areas to be welded are clean, free of moisture, and properly aligned.
Remove paint from any surface to be heated or welded. Painted surfaces give off unhealthy gases
when heated. Use a mask and proper skin protection when removing paint from any surface.
 If you remove the paint by sanding the objects, take care not to breathe the generated
dust. Protect yourself by wearing a mask.
 If you remove the paint by using chemical compounds, completely clean the surface using
plenty of soap and water. Chemicals generate unhealthy gases when heated.
Preheat parts to be welded to a temperature of 300ºF to 400ºF (150ºC to 200ºC). Run stringer
passes; minimize heat input and welding time by using short stringer beads to remove stress. Cool
slowly after welding. If temperature is 50ºF (10ºC) or below, wrap with an insulation blanket. A lo-
calized post weld heat treatment with a Rosebud torch should include at least two inches minimum
of the adjacent base metal and the weld. This heat treatment should raise the temperature of the
heated area to 400ºF to 500ºF (200ºC to 260ºC). Control of this step is critical to avoid embrittling
the steel.
Have a fire extinguisher and first aid
kit ready for emergencies. Know
how to operate the fire extinguisher
and know where the first aid is lo-
cated in case of an emergency.
Make sure to disconnect the batter-
ies. Failure to do so could result in
extensive machine damage to the
electronic system.
13
General Information
Recommended Welding Procedures
HOA Manufacturing high strength, low alloy steels require greater than normal precautions when
welding. Follow this list of welding recommendations and procedures when installing and maintaining
your coupler.
HOA Manufacturing HDX™ Cast Coupler Installation & User Manual

The couplers installation will require you to do the following basic steps:
1. Connect the coupler to the end of the excavator’s arm.
2. Route the hoses from the coupler up the excavator arm and boom, then down to the engine
compartment that houses the low-pressure pilot system.
3. Install the control valve and filter in the engine compartment. This will provide easy access to
the low-pressure pilot system, as well as, protection from the elements.
4. Mount the 3-light switch box in the cab of the excavator.
Helpful Hints Before Beginning Installation
Fully read the Installation Instructions section (pages 14-28) before beginning the installation.
Determine where you will need to mount the control valve and filter (these components are
mounted in the main engine compartment near the excavator’s pilot pressure system).
Determine where, in the excavator cab, you will need to mount the switch box.
Make sure you have the proper fittings needed to tie into the pilot pressure system and the
hydraulic return system. These fittings are not supplied with the Coupler Installation Kit.
Check to determine if the tubular hose bracket can be welded to the excavator’s H-link.
Determine the best route for running the hoses on the excavator. The hoses should not interfere
with other excavator components.
14
DANGER
Failure to comply with information in this HOA Manufacturing HDX™ Cast Coupler User Manual may result in
injury, death, damage to property and/or damage to the coupler. Ensure all personnel have read and
understand the information in this manual before attempting to install, maintain, and/or operate the HDX™
coupler.
Installation Instructions
Installation Preparation
This section will guide you through the necessary steps to install your HDX™ coupler. Review the infor-
mation provided in the General Information section (pages 3-13) before attempting to install your coupler.
Pay close attention to all safety message in this manual.
HOA Manufacturing HDX™ Cast Coupler Installation & User Manual

Place the excavator, coupler, and all tools and supplies needed in an open, unencumbered work
area. Make sure the machine and coupler are on flat, secure ground.
Inspect the coupler and all Coupler Installation Kit components for signs of damage.
Ensure the Coupler Installation Kit is complete and none of the components are damaged. If any
components are damaged or missing, notify your dealer.
Familiarize yourself with the components of the coupler (see Chart #3 on page 6) and the Coupler
Installation Kit (see Chart #5 on pages 7-9).
The coupler ships with a set of attachment pins. Remove these attachment pins from the coupler.
They are not case-hardened pins and are designed to be used in the ears of the bucket or
attachment.
You are now ready to begin the coupler installation.
15
Installation Instructions
Installation Preparation
Follow this reference list for necessary preparation steps before beginning the coupler installation.
WARNING
Avoid oil spills. Use containers, rags, and/or absorbent towels to contain any oil leakage. Dispose of all waste
oil, fluids, lubricants, and other hazardous waste properly.
Always use the proper safety protection such as: hard hats, work gloves, safety shoes, and safety glasses
when operating, maintaining, or installing this equipment.
HDX™ couplers are designed to be used only with a HOA Manufacturing Coupler Installation Kit. Installing a
coupler with anything other than components from a HOA Manufacturing Coupler Installation Kit results in an
unauthorized modification to the coupler. Any unauthorized modifications may impair function, affect
performance, and affect the life of the coupler, the excavator and/or the attachment. Unauthorized
modifications may result in injury or death. HOA Manufacturing disclaims any liability and responsibility
resulting from unauthorized modification. Unauthorized modification voids all warranties.
CAUTION
Never allow a hydraulic line or component to become contaminated. Contamination in the hydraulic system
can cause severe system damage. Contact your excavator dealer to obtain the proper caps and plugs used
on your model excavator.
Do not connect the HDX™ coupler to hydraulic pressures exceeding 1000 psi. The HDX™ coupler is
designed to operate off of the excavator’s low-pressure pilot system. Only connect the coupler to the
excavator’s low-pressure pilot system.
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16
Installation Instructions
Removing Attachment
The following steps are necessary to remove an existing attachment from the excavator before beginning
the coupler installation.
2. Unlock the safety lever.
3. Operate the attachment controls on the
excavator to position the attachment
securely on firm, level ground.
1. Make sure the throttle control is in the low
idle position. Start the engine. 4. Remove the retaining bolts from the pins.
5. Remove both the stick and link pin from the
arm-to-bucket connection.
6. Operate the excavator controls to remove
the excavator arm from between the ears
of the attachment.
7. Rest the excavator arm securely on firm,
level ground.
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Installation Instructions
Connecting Coupler to Excavator Arm
The following steps are necessary to connect your coupler unit to the excavator’s arm.
2. If the attachment pins, which were shipped
with the coupler, are still in the coupler,
remove the pins. You cannot use these
attachment pins to connect the coupler to
the excavator arm. You must use the pins
that came with your excavator. The
attachment pins, which were shipped with
the coupler, are only used in the ears of the
bucket or attachment.
3. If your machine requires O-rings, roll the O-
rings onto the coupler bosses.
4. You are now ready to connect the coupler
to the excavator arm. With the throttle
control in the low idle position, slowly
operate the excavator controls to align the
stick pin hole to the stick-side of the
coupler. Insert the stick machine pin. Use
the original stick machine pin, which came
with the excavator, to connect the coupler
to the stick. Use a rubber mallet to drive
the pin into place.
5. Slowly operate the bucket cylinder on the
excavator to align the excavator’s pivot link
hole with the link-side of the coupler. Insert
the link machine pin. Use the original link
machine pin, which came with the
excavator, to connect the coupler to the
pivot link. Use a rubber mallet to drive the
pin into place. A pry bar may be necessary
to help adjust the pivot link in order to ease
installation.
6. Secure the stick and link pins in place by
installing their respective retaining bolts
and nuts.
7. Your coupler is now connected to the exca-
vator arm.
CAUTION
Make sure you use the original machine pins from
your excavator to connect the coupler to the arm of
the excavator. Do not use the attachment pins,
which were shipped with the coupler, to connect the
coupler to the arm of the excavator.
1. Ensure the coupler is resting securely on
firm, level ground and pins are not in the
coupler.
HOA Manufacturing HDX™ Cast Coupler Installation & User Manual