Southworth Dura-Dock Dock Lift Series User manual

Southworth Products DDL Dock Lift ManualFebruary 19, 2019
Model:
Serial Number:
Date placed in
service:
Dura-Dock Dock Lift
Owner’s Manual
(DDL 5-59M, DDL6-59M & DL8-59M)
SOUTHWORTH PRODUCTS CORP.
P.O. Box 1380, Portland, ME 04104-1380
Telephone: [phone] • 207-878-0700
Fax: [phone]
www.SouthworthProducts.com

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Contents
1 Introduction.................................................................................................................................... 4
1.1 Responsibilities of Owner and Users.................................................................................. 4
1.2 Responsibilities of Operators.............................................................................................. 5
2 Safety.............................................................................................................................................. 6
2.1 Safety Alert Symbols ............................................................................................................ 7
2.2 Signal Words ......................................................................................................................... 7
2.3 Safety Devices....................................................................................................................... 7
3 Labeling.......................................................................................................................................... 7
3.1 Label Location Diagram ....................................................................................................... 8
4 Installation...................................................................................................................................... 9
4.1 External Power Unit .............................................................................................................. 9
4.2 Pit Installation........................................................................................................................ 9
4.3 Typical Pit Plan.................................................................................................................... 10
4.4 Recommended Pad Plan .....................................................................................................11
4.5 Alternative Pad Plan ........................................................................................................... 12
4.6 General Installation............................................................................................................. 13
5 Operation...................................................................................................................................... 14
5.1 Loading ................................................................................................................................ 15
6 Maintenance & Repair................................................................................................................. 15
6.1 Maintenance Devices.......................................................................................................... 16
6.2 Periodic Maintenance ......................................................................................................... 17
6.2.1 Weekly Maintenance................................................................................................... 17
6.2.2 Monthly Maintenance ................................................................................................. 17
6.2.3 Six Months................................................................................................................... 17
6.3 Relieving Hydraulic Pressure ............................................................................................ 18
6.4 Replacement Parts.............................................................................................................. 19
7 Troubleshooting .......................................................................................................................... 19
8 Electrical Information.................................................................................................................. 21
8.1 Wiring Schematic ................................................................................................................ 21
8.2 Control Panel....................................................................................................................... 22
9 Hydraulic Information ................................................................................................................. 23
9.1 Hydraulic Fluid Specications........................................................................................... 23
9.2 Hydraulic Schematic........................................................................................................... 23
9.3 Hydraulic Power Unit.......................................................................................................... 23
9.4 Hose Specications............................................................................................................ 23

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This label (Part No. 10095524) is required by California law.
For more information visit: www.P65Warnings.ca.gov
This lift is design and manufactured in accordance with
ANSI standard MH29.1 – “The Safety Requirements for
Industrial Scissors Lifts”.
9.5 Hydraulic Arrangements .................................................................................................... 24
9.5.1 Standard Hydraulic Arrangement ............................................................................. 24
9.5.2 Alternative Hydraulic Arrangement .......................................................................... 24
10 Warranty & Contact Information .............................................................................................. 25

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1. Introduction
1.1 Responsibilities of Owner and Users
Basic Principles - Owners/users shall apply sound principles of safety, training, inspection,
maintenance, and expected operating environment. It shall be the responsibility of the owner/user
to advise the manufacturer where deection may be critical to the application.
Manuals - Owners/users shall keep and maintain a copy of the operating and maintenance
manual(s) and ensure its availability to operating and maintenance personnel.
Inspection and Maintenance - It shall be the responsibility of the users to inspect and maintain
the industrial scissors lift as required to ensure proper operation. The frequency of inspection
and maintenance shall be based upon the manufacturer’s recommendations and be compatible
with operating conditions and the severity of the operating environment. Machinery that is not in
proper operating condition shall be immediately removed from service until repaired. Maintenance
and repairs shall be made by a qualied person and the repairs shall be in conformance with the
manufacturer’s recommendations.
Maintenance Safety Precautions - Before adjustments and repairs are started on the machine,
the following precautions shall be taken as applicable:
1. Remove the load from the load enclosure.
2. Lower the platform to the full down position.
3. Relieve system pressure from all circuits before loosening or removing any components.
4. All controls in the “off’ position and all operating features secured from inadvertent motion
by brakes, blocks, or other means.
5. Disconnect power and follow established owner/user lockout/tag out policies.
6. Follow precautions and directions as specied by the manufacturer.
Replacement Parts - When parts or components are replaced, they shall be replaced with parts
or components approved by the original manufacturer.
Maintenance Training - The user shall ensure only qualied personnel inspect and maintain the
machine in accordance with the manufacturers recommendations.
Operator Training - An owner/user, who directs or authorizes an individual to operate the
machine shall ensure that the individual has been:
1. Trained in accordance with the manufacturer’s operating manual.
2. Made aware of the responsibilities of operators as outlined in section 1.4 of this manual.
3. Retrained, if necessary, based on the owners/user’s observation and evaluation of the
operator.
Modications and additions shall not be performed without the manufacturer’s prior written
approval. Where such authorization is granted, capacity, operation, and maintenance instruction
plates, tags, or decals shall be changed accordingly.

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1.2 Responsibilities of Operators
Basic Principles - Operators shall apply sound principles of safety and good judgment in
the application and operation of the machine with consideration given to its intended use
and expected operating environment. Since the operator is in direct control of the machine,
conformance with good safety practices is the responsibility of the operator. The operator shall
make decisions on the use and operation with due consideration for the fact that his or her own
safety as well as the safety of other personnel on or near the machine is dependent on those
decisions.
1. General Training - Only personnel who have received general instructions regarding the
inspection, application and operation of machine, including recognition and avoidance of
hazards associated with their operation, shall operate the machine. Such topics covered
shall include, but not necessarily be limited to, the following issues and requirements:
2. A pre-start inspection
3. Responsibilities associated with problems or malfunctions affecting the operation of the
machine.
4. Factors affecting stability
5. The purpose of placards and decals
6. Workplace inspection
7. Safety rules and regulations
8. Authorization to operate
9. Operator warnings and instructions
10.Actual operation of the machine. Under the direction of a qualied person, the trainee shall
operate the machine for a sufcient period of time to demonstrate prociency in actual
operation of the machine.
Pre-start Inspection - Before use each day or at the beginning of each shift, the machine shall
be given a visual inspection and functional test including but not limited to the following:
1. Operating and emergency controls
2. Safety devices
3. Hydraulic system leaks
4. Electrical cables and wiring harness
5. Loose or missing parts
6. Nameplates, precautionary and instructional markings and/or labeling
7. Guarding system
8. Items specied by the manufacturer
Problem or Malfunctions - Any problems or malfunctions that affect the safety of operations shall
be repaired prior to the use of the machine.
Before Operations - The operator shall:
1. Read and understand the manufacturer’s operating instruction(s) and user’s safety rules or
have them explained
2. Understand all labels, warnings, and instructions displayed on the machine or have them
explained.

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Workplace Inspections - Before the machine is used and during use, the operator shall check
the area in which the machine is to be used for possible hazards such as, but not limited to:
1. Bumps, oor obstructions and uneven surfaces
2. Overhead obstructions and electrical hazards
3. Presence of unauthorized persons
4. Other possible unsafe conditions as noted in the operating manual.
Operator Warnings and Instructions - The operator shall ensure the operation of the machine
is in compliance with the following:
Guarding system - Guarding shall be installed and positioned, and access gates or openings
shall be secured per the manufacturer’s instructions.
Distribution of load - The load and its distribution on the platform shall be in accordance with the
manufacturer’s rated capacity for that specic conguration.
Maintaining overhead clearance - The operator shall ensure that adequate clearance is
maintained from overhead obstructions and energized electrical conductors and parts.
Point of Operation - The operator shall not place any part of their body under the platform.
Precaution for moving equipment - When other moving equipment or vehicles are present,
special precautions shall be taken to comply with the safety standards established for the
workplace.
Reporting problems or malfunctions - The operator shall immediately report to a supervisor
any problem(s) or malfunction(s) that become evident during operation. The operator shall ensure
all problems and malfunctions that affect the safety of operations are repaired prior to continued
use.
Capacity limitation - Rated capacity shall not be exceeded when loads are transferred to the
load enclosure.
Work area - The operator shall ensure the area surrounding the machine is clear of personnel
and equipment before lowering the load enclosure.
Securing the machine - The operator shall comply with the means and procedures provided to
protect against use by an unauthorized person(s).
Altering safety devices - Safety devices shall not be altered or disabled.
Modications or alterations of the machine or the fabrication and attaching of frameworks or the
mounting of attachments to the machine or the guarding system shall only be accomplished with
prior written permission of the manufacturer.
Assistance to the operator - If an operator encounters any suspected malfunction or any hazard
or potentially unsafe condition relating to capacity, intended use or safe operation the operator
shall cease operation of the machine and request further instruction from the owner/user.
Problems or malfunctions - Any problem(s) or malfunction(s) that affect the safety of operations
shall be repaired prior to the use of the machine.
2. Safety
All personnel installing, operating, and maintaining this machine shall read and understand this
manual. For questions or concerns contact the manufacturer.
This machine shall be installed, operated, and maintained by trained and/or qualied personnel
only.

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2.1 Safety Alert Symbols
A symbol that indicates a hazard. It is composed of an equilateral triangle surrounding an
exclamation mark. The safety alert symbol is only used on hazard alerting signs. It is not used on
safety notice and safety instructions signs.
A – For use with DANGER signal word; (safety white triangle, safety red exclamation mark, safety
red background)
B – For use with WARNING signal word; (safety black triangle, safety orange exclamation mark)
C – For use with CAUTION signal word; (safety black triangle, safety yellow exclamation mark)
D – For use with DANGER, WARNING, or CAUTION signal words; (safety yellow triangle with a
safety black border and safety black exclamation mark
2.2 Signal Words
Indicates a hazardous situation that, if not avoided, will result in death
or serious injury.
Indicates a hazardous situation that, if not avoided, could result in
death or serious injury.
Indicates a hazardous situation that, if not avoided, could result in
minor or moderate injury.
Indicates information considered important, but not hazard-related
(e.g., messages relating to property damage).
2.3 Safety Devices
This machine is equipped with devices and features to protect the operator and nearby personnel
from severe injury or death. These features and devices shall be installed and functioning
correctly during operation.
This machine is equipped with beveled toe guards on the platform, which meet the requirements
of ANSI MH 29.1 and requirements for pit installation.
3. Labeling
This machine has labeling to indicate potential hazards this machine may pose when operating
and/or maintaining the machine. All labels must be legible. If any label is missing, damaged, or
otherwise illegible contact the manufacturer for replacement labels.
ABCD

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3.1 Label Location Diagram
BK-LD TAG SOUTHWORTH 5900158

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4. Installation
Installation of this machine shall be performed by trained and/ or qualied personnel
only. The owner/ installer is responsible obtaining any necessary permissions and/ or
permits. Follow all applicable codes and ordinances. Read and understand all safety and
installation information in this manual.
Before installation, remove all shipping materials and verify all components on the packing
list were received. Inspect the machine, all components, wiring and electrical connections,
hydraulic hoses and ttings for damage. If components are missing or damage is found contact
the manufacturer before continuing installation. If not being installed in a pit see Typical and
Alternative Pad Plan sections
To avoid death or serious injury:
• Pinch points and Crush Hazards exist when moving and transporting the machine.
Do not enter under any equipment while moving or transport. Keep hands, feet, and
loose clothing away from moving equipment.
• This machine must be installed on a solid, stable, level surface or machine will be
unstable and can lead to injury. Do not install on asphalt or other unstable surface.
• Never enter beneath the platform unless the machine is unloaded and secured
against lowering using the maintenance device. See Maintenance Devices section.
Use appropriate lifting device to lift the machine. Use a load spreader
to lift the machine. Lift the machine using the provided lifting eye-bolts
only. Do not lift the machine by the platform.
This machine must be properly secured to the oor/ ground before
operation or the machine may be damaged.
High Voltage: Electrical service and installation must be performed by
trained and/ or qualied personnel. Lock-out/ tag-out the power source
before installation.
Electric motors create sparks. Do not install the power unit in an area
where ammable gases may be present.
4.1 External Power Unit
External power units should be placed within thirty feet (hose length) of the machine to avoid
excess pressure drops. External power units must be protected from moisture and weather.
4.2 Pit Installation
Do not install this machine in a pit unless the machine has been
designed for such installation. Shear points exist and can cause severe
injury.
Platforms traveling below oor level may require guarding in
accordance with ANSI MH 29.1. Guarding must be installed before
operation.
This machine is equipped with beveled toe guards which meet the MH
29.1 guarding requirements.
1. Verify that the pit dimensions match the pit plan.
2. Verify that pit is clear of tools and other debris before lowering the machine into the pit.
3. Follow General Installation instructions to complete the installation.

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4.3 Typical Pit Plan
FROM ANY DIRECTION
INCLUDING ENTRY FROM
BOTTOM OF PIT SUMP.STEP REQUIRED FOR BRIDGE
PLATE HINGE CLEARANCE
MUST BE SQUARE ( 1/2")
ACROSS CORNERS.
3" X 3" X 1/4" ANGLE BY
PIT CONTRACTOR. ALL
CORNERS TO BE
SECURELY WELDED. PIT
CONDUIT ENTRY CAN BE
COUPLINGS FOR
HYDRAULIC
CONNECTIONS
1 1/2"
BRIDGE
+1-1/2"
PLATFORM LENGTH + 1-1/2"
WIDTH
LENGTH + 1/2"
BRIDGE PLATE
PLATFORM
PLATE
WIDTH
+1/2"
2" CONDUIT
3/4" LAG HOLES
LAG WITH5/8" MIN.
SLEEVE ANCHORS
(BY INSTALLER)
VODIS
COMPACTED WITH NO
ANGLES MUST BE WELL
CONCRETE BEHIND CURB
FRONT OF PIT
ALIGNED WITH
CONCRETE ANCHORS TO
BOLLARDS TO BE
CENTER LINE OF
FROM EACH END.
12" O.C. WITH ONE 3"
1/2" X 6" LOCATED
PREVENT STANDING WATER
PIT DRAIN AS REQUIRED TO
BE
IN PIT. (BY CONTRACTOR)
CROSS HATCHING INDICATES AREAS OF
•
BASE FROM THE MUST BE SHIMMED AND
OR GROUTED AFTER LEVELING OF THE
BASE FRAME TO ENSURE PROPER BASE
FRAME SUPPORT.
CONDUIT RUN IS REQUIRED FOR ROUTING
•
OF HYDRAULIC HOSES AND ELECTRICAL
WIRING UNLESS ALTERNATIVE
ARRANGEMENTS ARE REQUESTED.
2" ELECTRICAL CONDUIT USED WHEN 1/2"
•
HYDRAULIC HOSE, VENT LINE, AND
ELECTRICAL LEADS ARE TO BE INSTALLED
FROM POWER UNIT TO LIFT (BY PIT
CONTRACTOR).
8" BOLLARDS
36"
STEEL PIPE FILLED
48"
1/2"
3"
6" +1/2"
HEIGHT
LOW
(BY CONTRACTOR)
WITH CONCRETE
1/2" SHIM
UNDER EACH
LAG PLATE FOR
PROPER DRAINAGE

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4.4 Recommended Pad Plan
Use of a sump/drain for proper drainage and a conduit run for hydraulic/ electrical routing
in pad is recommended. If no sump/drain and conduit run is provided see Alternative Pad
Plan .
86" BASE FRAME
2° SLOPE GRADE
AWAY FROM PAD
ANCHORS
THROW OVER
PLATE AREA
5/8"
(MINIMUM) SLEEVE
4X LAG WITH
CONDUIT ROUTE CAN BE
FROM ANY DIRECTION
INCLUDING FROM BOTTOM
OF PIT SUMP
9"
2" CONDUIT
FRAME
BASE
12"
8" STEEL
PIPE
FILLED WITH
CONCRETE TYP.
(BY CONTRACTOR)
72"
PAD
7 1/2"
ANCHORS
78" LAGS
5"
5"
6"
12"
7 1/2"
57"
6"
2X
54"
96" PAD
NOTES:
CROSS HATCHING INDICATES AREAS OF•
BASE FRAME THAT MUST BE SHIMMED
AND/OR GROUTED AFTER LEVELING OF THE
BASE FRAME TO ENSURE PROPER BASE
FRAME SUPPORT.
CONDUIT RUN IS RECOMMENDED FOR•
ROUTING OF HYDRAULIC HOSES AND
ELECTRICAL WIRING.
2" ELECTRICAL CONDUIT USED WHEN 1/2"•
HYDRAULIC HOSE, VENT LINE, AND
ELECTRICAL LEADS ARE TO BE INSTALLED
FROM POWER UNIT TO LIFT (BY
CONTRACTOR).
COUPLINGS FOR
HYDRAULIC
CONNECTIONS
HINGE END OF BASE
FOR MODEL DDL5-59
WITH 72"X96" PLATFORM
NO VOIDS
WELL COMPACTED WITH
SMOOTH AND LEVEL
SURFACE MUST BE
POSTS TO BE ALIGNED WITH
EDGE OF PAD
CENTER LINE OF BUMPER
CONCRETE PAD MUST BE
PAD DRAIN AS REQUIRED TO
PREVENT STANDING WATER
ON PAD (BY CONTRACTOR)
8"
36"
48"
36"
3"
6"
ROLLER END

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4.5 Alternative Pad Plan
If sump/drain is not used lift will require 1/2” shims under the lag plates to allow proper
water drainage. The base frame must be shimmed and/or grouted according to the pad
plan to ensure the base frame is properly supported. Hydraulic connections are to be
made at the couplings on the roller end of the base frame.
86"
2° SLOPE GRADE
AWAY FROM PAD
ANCHORS
(MINIMUM) SLEEVE
4X LAG WITH 5/8"
PLATE AREA
THROW OVER
COUPLINGS FOR
HYDRAULIC
CONNECTIONS. FOR
MACHINES MOUNTED
ON
PADS WITH NO CONDUIT
ROUTING PROVIDED.
7 1/2"
6"
ANCHORS
57"
FILLED WITH
CONCRETE TYP.
(BY CONTRACTOR)
8" STEEL PIPE
96" PAD
72"
PAD
FRAME
78"
9"
7 1/2"
5" 2X
54"
BASE
6"
NOTES:
IF SUMP IS NOT USED, THE BASE FRAME•
MUST BE RAISED 1/2" TO ALLOW FOR
PROPER WATER DRAINAGE.
CROSS HATCHING INDICATES AREAS OF•
BASE FRAME THAT MUST BE SHIMMED
AND/OR GROUTED AFTER LEVELING OF THE
BASE FRAME TO ENSURE PROPER BASE
FRAME SUPPORT.
IF CONDUIT RUN IN PAD IS NOT USED FOR•
HYDRAULIC ROUTING CONNECTIONS ARE
TO BE MADE AT COUPLINGS ON ROLLER
END OF BASE FRAME.
HINGE END OF BASE
FOR MODEL DDL5-59
WITH 72"X96" PLATFORM
SURFACE MUST BE
SMOOTH AND LEVEL WELL COMPACTED WITH
NO VOIDS
CONCRETE PAD MUST BE
CENTER LINE OF BUMPER
POSTS TO BE ALIGNED WITH
EDGE OF PAD
36"
48"
8"
ROLLER END

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4.6 General Installation
1. Attach a chain or lifting strap, with an appropriate load spreader, to the main lifting eyes.
The chain or strap must pull on the lifting eyes vertically.
2. Using an appropriate lifting device, carefully move the machine into position.
3. Remove the lifting eyes and install them into the second set of holes. The second set of
holes have a nut welded to the bottom of the platform and are used to manually raise the
platform for access during installation. Reattach the chain or strap.
Eye bolts must be removed from holes securing the platform to the base
frame (holes along platform center line) before attempting to raise the
platform.
4. Using the eyes bolts, raise the platform and engage the maintenance device. See the
Maintenance Devices section. Ensure the roller end of the platform is not is not lifted off
of the upper rollers.
5. Remove the eye bolts and save them for future use, if needed.
6. Ensure the machine is level. If necessary use shims beneath the lag plates. All load bearing
points of the base frame must be fully supported by using grout beneath the base frame.
An improperly supported base frame can cause excess wear and/or
permanent damage to the machine.
INSTALL EYE BOLTS INTO SECOND SET OF
HOLES TO MANUALLY RAISE THE PLATFORM
(OFF PLATFORM CENTERLINE)
LIFTING EYE POSITION FOR
MOVING ENTIRE MACHINE
(ALONG PLATFORM CENTERLINE)
USE LOAD SPREADER SO THAT CHAIN/
STRAPS PULLS VERTICALLY ON LIFTING
EYES
CROSS HATCHING INDICATES AREAS THAT
HINGE END
ROLLER TRACKS (BOTH SIDES)
NEED TO BE SHIMMED AND/OR GROUTED,
ONCE LEVELED.
FRONT ROLL-OVER SUPPORT
SIDE ROLL-OVER
SUPPORT (BOTH SIDES)
LAG PLATES (ALL
FOUR CORNERS)

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7. Anchor the machine using appropriate anchors.
8. Clear the hydraulic lines by ushing with compressed air.
Hydraulic lines must be clear of debris before connecting or damage
may occur when the unit is powered.
If hoses & electrical wiring are not routed through conduit, hoses and
wiring must be protected from damage by other means.
9. Make all hydraulic connections according the hydraulic schematic.– See Hydraulic
Information section for specications and schematics.
10.Make all electrical connections according the wiring schematic.– See Electrical
Information section for specications and schematics.
11. If applicable, install and anchor ramp.
12.Install handrails and snap cables/ chains.
13.Check all hydraulic hoses and connections, wiring and electrical connections, and other
components for proper installation and damage.
14.Cycle the lift to test function. If platform does not begin to raise after a few seconds, see
Troubleshooting section.
5. Operation
Before operating this machine, read and understand this manual. Inspect the machine for
excessive wear and/ or damage. If excessive wear or damage is found, remove the machine
from service and contact maintenance personnel. Inspect all precautionary labeling. If any
label is missing or illegible contact the manufacturer for replacement labels. Ensure area is free of
debris.
Before raising or lowering, raise throw over plate(s) and bridge plate(s)
to avoid damaging the plate(s).
BEFORE PERSONNEL MAY
RIDE ON LIFT
MUST BE SECURED
ALL SNAP CHAINS/CABLES
THROW OVER PLATE
MUST BE IN RAISED
POSITION BEFORE
RAISING OR LOWERING
THE PLATFORM
ALL HANDRAILS MUST BE
INSTALLED AND SECURED
BEFORE PERSONNEL MAY
RIDE ON LIFT

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To avoid death or serious injury:
• Only trained and/or qualied personnel shall operate this machine.
• Personnel are not permitted on the platform during operation unless handrails and
snap chains/cables are installed.
• Loads that may shift during operating must be secured before operating.
• Keep hands, feet, and loose clothing away from moving parts.
• Do not enter beneath the platform until the load has been removed and the machine
has been secured against lowering with the maintenance device(s).
• Do not load or unload the machine while moving.
• The load’s center of mass must be centered on the platform. Uneven or off center
loading may cause excessive wear or permanent damage.
• During operation, operator must be in view of the machine at all times.
When not in use the platform is to be in the fully lowered position.
To raise the machine, press and hold the UP button on the controls. Release the button when
the platform is at the desired height.
To lower the machine, press and hold the DOWN button on the controls. Release the button
when the platform is at the desired height.
5.1 Loading
All loads should be centered on the platform. Uneven loading can lead to excessive wear or
damage. Always secure loads that may roll or shift during travel.
6. Maintenance & Repair
To avoid death or serious injury:
• Only trained and/ or qualied personnel shall perform maintenance or repair of this
machine.
• Pinch points exist, keep hands, feet, and loose clothing away from moving parts.
• Always use appropriate Personal Protective Equipment when performing and
maintenance or repair.
• Disconnect and lock out electrical supply before performing any maintenance or
repair
• Do not adjust the hydraulic pressure relief valve. This valve is pre-set and
adjustment may cause the machine to fail.
• Before performing maintenance or repair to the hydraulic components, relieve
pressure in the hydraulic system. See Relieving Hydraulic Pressure section.
• Pressurized uids can penetrate skin and cause severe injury. Do not use hands or
other body parts to detect hydraulic leaks.
• Do not enter beneath the platform until the load has been removed and the machine
is secured against lowering with the maintenance device(s). See Maintenance
Devices section.

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6.1 Maintenance Devices
To avoid death or serious injury:
• DO NOT enter beneath the platform until load has been removed and the machine is
secured against lowering using the supplied maintenance device(s).
• The supplied maintenance device(s) are designed to support the weight of
an UNLOADED machine only. Failure to remove the load before engaging
the maintenance devices may result in failure and allow the machine to fall
unexpectedly.
Before performing any maintenance or repair:
1. Remove any load on the platform of the machine.
2. Verify that all personnel and debris are clear of the work area.
3. Raise the lift to the fully raised position.
4. Engage maintenance device as shown in the diagram.
When engaged the maintenance device must rest on the underside of
the platform. Damage may occur if the maintenance device is resting on
the structural reinforcements. Maintenance device to be used on hinge
end of machine only.
5. Slowly lower the machine until the weight of the machine is supported by the maintenance
device(s). Continue to hold the down button for ve to ten seconds after the platform stops
to relieve hydraulic system pressure.
6. Disconnect electrical supply and
lock out the machine to prevent
unintended actuation of the
machine.
7. After maintenance or repair is
complete, verify all tools, debris,
and personnel are clear of the area.
Clean up any spills. Re-energize the
machine.
8. Raise the machine to the fully raised
position.
9. Disengage the maintenance device
and stow the maintenance device.
10.Lower the machine to the fully
lowered position.
11. Test for proper operation.
RAISE THE PLATFORM TO THE FULLY1.
RAISED POSITION
REMOVE THE MAINTENANCE DEVICE2.
FROM THE STOWED POSITION AND
PLACE THE END OVER THE POST.
LOWER THE PLATFORM UNTIL3.
RESTING ON THE MAINTENANCE
DEVICE. WHEN ENGAGED, THE
MAINTENANCE DEVICE MUST REST ON
THE UNDERSIDE OF THE PLATFORM.
DAMAGE MAY OCCUR IF
MAINTENANCE DEVICE IS RESTING ON
STRUCTURAL REINFORCEMENTS
MAINTENANCE DEVICE STOWED
POST
POST
MAINTENANCE DEVICE ENGAGED
WHEN ENGAGED, THE
MAINTENANCE DEVICE MUST
REST ON THE UNDERSIDE OF
THE PLATFORM. DAMAGE MAY
OCCUR IF MAINTENANCE
DEVICE IS RESTING ON
STRUCTURAL
REINFORCEMENTS
HINGE END
HINGE END

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6.2 Periodic Maintenance
Before each use ensure area is clear of debris and sump/drain is clear. Inspect the machine
for excessive wear or damage and ensure all precautionary labeling is legible. Inspect railings,
verify cables/chains are in place and in good condition. Verify push button switch and cord are
functioning and are not damaged.
6.2.1. Weekly Maintenance
• Inspect leg rollers, center pivot pins and bushings, and leg hinge pins and bushings for
excessive wear or damage. Repair or replace as necessary.
• Inspect machine for loose of broken fasteners. Repair or replace as necessary.
• Inspect labeling. If any label is damaged or otherwise illegible contact the manufacturer
for replacement labels.
6.2.2. Monthly Maintenance
• Perform Weekly Maintenance.
• Apply a light oil or PTFE lubricant to non-greased pivot points or rollers.
• Inspect the appearance of the hydraulic uid. The uid should be transparent and clear
of debris.
• Inspect all hydraulic hoses and ttings. Repair or replace as necessary.
• Inspect all electrical wiring and connections. Repair or replace as necessary.
• Inspect limit switches, if applicable. Repair, replace, or adjust as necessary.
6.2.3. Six Months
• Perform Monthly and Weekly maintenance.
• Inspect the hydraulic cylinder and return line. If excessive uid exists in the vent line,
the cylinder may need to be repacked or replaced.
• Change hydraulic uid. Clean the suction screen and vent cap. Replace pressure line or
return line lter element (if equipped).
BASE FRAME
RAILINGS (BOTH SIDES)
HYDRAULIC POWER UNIT
(STOWED)
MAINTENANCE
PLATFORM)
PULL CABLE
PLATFORM
SNAP CABLES
(BOTH ENDS OF
DEVICE
HYDRAULIC
CYLINDER PINS
(EACH CYLINDER)
THROW OVER
PLATE
CENTER PIVOT
PINS/BUSHINGS
(BOTH SIDES)
UPPER/LOWER LEG HINGE
PINS/BUSHINGS (BOTH SIDES)
UPPER/LOWER
ROLLERS
(BOTH SIDES)
HYDRAULIC
CYLINDERS

Southworth Products DDL Dock Lift Manual
18
6.3 Relieving Hydraulic Pressure
If the machine is operating normally, hydraulic system pressure can be relieved by lowering the
platform to the fully lowered position or on maintenance device and continuing to hold the down
button for ve to ten seconds.
If the platform is raised and will not lower:
Crush Hazard – Do not enter under the platform.
Remove load before performing any maintenance or repair.
Disconnect and lockout electrical power before performing maintenance
or repair.
Failure to securely block the platform from lowering will allow the
platform to fall uncontrolled when system pressure is relieved, causing
severe injury or death - use only supplied maintenance device.
High pressure uid can cause severe injury or death. Always use proper
personal protective equipment when performing any maintenance or
repair.
1. Thread the lifting eyes into holes on the platform for manually raising the platform (holes off
the center line of the platform). See General Installation Section numbers 1-5.
2. Attach chains/ straps and load spreader to the lifting eyes.
3. Using an appropriate lifting device, slowly pull the chains/ straps until they are taught and
will support the platform when hydraulic pressure is relieved. If the platform is not in the
fully raised position, continue to pull the platform up until it reaches the fully raised position.
Platform weight: approximately 2000 lb.
When lifting the platform by the lifting eyes, ensure cable/chain/straps
pull vertically on the lifting eyes.
4. Ensure platform is secured and will not fall as hydraulic pressure is relieved.
5. Carefully and slowly loosen the hydraulic tting on the input side of the adjustable ow
control shown in the diagram to relieve system pressure. Use an appropriate, clean,
container to catch hydraulic uid in the hoses. Use an oil absorbent to clean up any spills.
Uncontaminated uid can be reused.
6. Engage the maintenance device. - See Maintenance Devices section.
7. Slowly lower the platform until resting on the maintenance device.
DOWN SOLENOID/ VALVE
PRESSURE
PUMP
MOTOR
CONTROL PANEL
TO RELIEVE SYSTEM
DISCONNECT
HYDRAULIC HOSE
FROM THIS FITTING
RESERVOIR
ADUJUSTABLE DOWN
FLOW CONTROL

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19
6.4 Replacement Parts
Southworth Products has carefully chosen the components in your lift to be the best available
for the purpose. Replacement parts should be identical to the original equipment. Southworth
Products will not be responsible for equipment failures resulting from the use of incorrect
replacement parts or from unauthorized modications of the machine.
Southworth Products will gladly supply you with replacement parts for your Southworth Products
lift. With your order, please include the model number and the serial number of the lift. You
can nd these numbers on the name plate, which is located on the crossbar at the base of the
cylinder(s). When you are ordering parts for a cylinder, also include the cylinder number. This is
stamped on the base of the cylinder housing.
To order replacement parts, please call the Parts Department. See Warranty & Contact
Information section. Parts are shipped subject to the following terms:
• FOB factory
• Returns only with the approval of our parts department.
• Payment net 30 days (except parts covered by warranty).
• Freight collect (except parts covered by warranty).
• The warranty for repair parts is 30 days from date of shipment.
Parts replaced under warranty are on a “charge-credit” basis. We will invoice you when we ship
the replacement part, then credit you when you return the worn or damaged part, and we verify
that it is covered by our warranty. Labor is not covered under warranty for Parts orders.
7. Troubleshooting
PROBLEM POSSIBLE CAUSE CHECK
Lift will not raise
Load too heavy Make sure the load does not exceed the rated
capacity.
Power unit not receiving
power.
Verify that the power unit is receiving power. See
Electrical Information Section.
Hand controls may be
malfunctioning or may not be
receiving power.
Verify that the controls are receiving power
and are functioning correctly. See Electrical
Information Section.
Motor contactor may be
malfunctioning.
Verify motor contactor is functioning. See
Electrical Information Section.
Motor may be turning in wrong
direction.
Swap any two phases of the motor power leads.
Hydraulic Fluid low With lift in fully lowered position the uid level
should be approximately 3/4” from the top of the
tank.
Lift has reached it upper limit. Upper limit switch may need to be adjusted
Motor voltage too low Supply voltage must be ± 10% of the rated
voltage at the motor terminals.
Tank vent plugged Make sure vent plug on hydraulic tank is
installed and not blocked.

Southworth Products DDL Dock Lift Manual
20
PROBLEM POSSIBLE CAUSE CHECK
Lift will not raise
Suction lter is clogged Clean suction lter.
Vacuum leak in the suction
line
Check all ttings and hoses for damage or loose
connections.
Down valve may be energized Check wiring to down valve and solenoid valve.
Missing coupling between
motor and pump (if
applicable).
Check to make sure the coupling between the
pump and motor has been installed.(Machines
manufactured before September 2012).
Pressure relief valve is
activated.
If there is a loud squealing noise the pressure
relief valve may be activated. – Contact
Customer Service for assistance.
External Hydraulic leak Inspect all hoses, connections, and cylinders for
leaks.
Lift fails to hold
(Drifts down)
Down valve may be leaking
internally.
Remove the down valve and inspect for debris
which may be preventing it from closing.
Contact Customer Service for procedure.
Down valve may be energized Check the solenoid with a volt meter.
Cylinder may be leaking Check for uid leaks.
Lift will not lower
Down valve may not be
energized
Check for power to the solenoid valve with a volt
meter while pressing the down button.
Down Flow control may need
to be adjusted
Adjust down ow control as needed.
Lift raises too
slowly
Voltage may be low Check voltage at motor. Supply voltage must
be ± 10% of the rated voltage at the motor
terminals.
Suction lter, breather cap, or
pressure line may be clogged
Remove necessary components and clean.
Pump may be overheating
due to insufcient oil
Check uid level and viscosity.
Lift lowers too
slowly
Down valve may not be fully
opening or may be partially
blocked or stuck closed.
Remove the down valve and clean. - Contact
Customer Service for procedure.
Flow control may need to be
adjusted
Adjust the ow control as necessary.
Pressure relief valve is
activated.
If there is a loud squealing noise the pressure
relief valve may be activated. – Contact the
manufacturer for assistance.