Poweramp CM Series User manual

CM-Series
Dock Leveler
Owner’s/User’s Manual
Printed in U.S.A.
Copyright ©2003
Manual No. 4111-0006
September 2010
POWERAMP • Division of Systems, Inc. • W194 N11481 McCormick Drive • Germantown, WI 53022
800.643.5424 • fax: [phone] • www.docksystemsinc.com • [email protected]

Page
Safety
Recognize Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
General Operational Safety Precautions . . . . . . . . . . . . . . . . . . . . . . 1
Operational Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Maintenance Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Safety Decals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Owner’s/User’s Responsibilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Introduction
General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Dock Leveler Stock Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Component Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Installation
Prepare Pit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Prepare Dock Leveler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Install Dock Leveler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Operation
Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Ramp Loading/Unloading Instructions . . . . . . . . . . . . . . . . . . . . 19
End Loading/Unloading Instructions . . . . . . . . . . . . . . . . . . . . . 20
Maintenance
Service Dock Leveler Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Periodic Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Adjustments
Adjust Lift Arm Spring and Lip Assist Spring Tension . . . . . . . . . . 24
Adjust Lip Stop Bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Troubleshooting
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Parts
Hold-Down Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Frame Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Platform Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Toe Guard/Weather Seal—Optional . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Miscellaneous
Customer Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Back Cover
Table of Contents

SAFETY
1
4111-0006 — Sept 2010
Recognize Safety Information
Read and understand the operating instructions and
become thoroughly familiar with the equipment and
its controls before operating the dock leveler.
Never operate a dock leveler while a safety device or
guard is removed or disconnected.
Never remove DANGER, WARNING, or CAUTION
signs or decals on the equipment unless replacing
them.
General Operational Safety
Precautions
DO NOT activate the equipment until all unauthorized
personnel in the area have been warned and have
moved outside the operating zone.
Remove any tools or foreign objects from the
operating zone before starting.
Keep the operating zone free of obstacles that could
cause a person to trip or fall.
The use of the word DANGER signifies the
presence of an extreme hazard or unsafe practice
which will most likely result in severe injury or
death.
Safety-Alert Symbol
The Safety-Alert Symbol identifies important safety
messages on equipment, safety signs, in manuals,
or elsewhere. When you see this symbol, be alert
to the possibility of personal injury or death. Follow
the instructions in the safety message.
The use of the word WARNING signifies the
presence of a serious hazard or unsafe practice
which may result in serious injury or death.
IMPORTANT
IMPORTANT
The use of the word IMPORTANT is to draw
attention to a procedure that needs to be followed
to prevent machine damage.
The use of the word CAUTION signifies possible
hazard or unsafe practice which could result in
personal injury.
Op
era
tin
g
Zo
ne
O
peratin
gZon
e

SAFETY
24111-0006 — Sept 2010
Learn the safe way to operate this equipment. Read and understand the
manufacturer's instructions. If you have any questions, ask your supervisor.
Operational Safety Precautions
Stay clear of dock leveling device when freight
carrier is entering or leaving area.
Do not move or use the dock leveling device if
anyone is under or in front of it.
Keep hands and feet clear of pinch points. Avoid
putting any part of your body near moving parts.
Chock/restrain all freight carriers. Never remove
the wheel chocks until loading or unloading is
finished and truck driver has been given
permission to drive away.
Do not use a broken or damaged dock leveling
device. Make sure proper service and
maintenance procedures have been performed
before using.
Make sure lip overlaps onto trailer at least 4 in.
(102 mm).
Keep a safe distance from both side edges.

SAFETY
3
4111-0006 — Sept 2010
Do not use dock leveling device if freight carrier is
too high or too low.
Do not overload the dock leveling device.
Do not operate any equipment while under the
influence of alcohol or drugs.
Do not leave equipment or material unattended on
dock leveling device.

SAFETY
44111-0006 — Sept 2010
Maintenance Safety Precautions
ALWAYS stand clear of dock leveler lip when
working in front of the dock leveler. Failure to do
this may result in serious personal injury or death.
DO NOT grind or weld if hydraulic fluid or other
flammable liquid is present on the surface to be
ground or welded
DO NOT grind or weld if uncontained hydraulic
fluid or other flammable liquid is present. Stray
sparks can ignite spills or leaks near the work area.
Always clean up the oil leaks and spills before
proceeding with grinding or welding.
Always keep a fire extinguisher of the proper type
nearby when grinding or welding.
Failure to follow these instructions may result in
serious personal injury or death.
Always post safety warnings and barricade the
work area at dock level and ground level to
prevent unauthorized use of the unit before
maintenance is complete.
The maintenance prop must be in the upright
"service" position when working under the dock
leveler. For maximum protection, use an OSHA
approved locking device to lock the maintenance
prop in the service position. Only the person
servicing the equipment should have the key to
unlock the device.

SAFETY
5
4111-0006 — Sept 2010
Safety Decals
Every 90 days (quarterly) inspect all safety labels and tags
to ensure they are on the dock leveler and are easily leg-
ible. If any are missing or require replacement, please call
1-800-643-5424 for replacements.
CRUSH HAZARD
Maintenance prop must
support leveler behind bar.
Do not force maintenance
prop forward of bar to
support lip. Refer to
owner’s/user’s manual for
proper use. Failure to
comply will result in
death or serious injury.
DANGER
1751-0727
Unsupported dock leveler
ramps can lower unexpectedly.
Before allowing vehicle to leave
the dock always:
!Ensure that no equipment,
material or people are on the
dock leveler.
!Return the dock leveler to its
stored position at dock level.
Failure to follow posted instructions will result in death or serious injury.
SAFETY INFORMATION
Call 262.255.1510 for replacement placards, warning labels, or owner’s/user’s manuals.
Operation
1. Read and follow all instructions and
warnings in the owner’s/user’s
manual.
2. Use of dock leveler restricted to
trained operators
3. Always chock trailer wheels or
engage truck restraint before
operating dock leveler or beginning to
load or unload.
4. Never use hands or equipment to
move the ramp or lip
5. Before activating dock leveler:
¥Ensure trailer is backed in against
bumpers.
¥Remove any end loads if required.
¥Check trailer alignment to avoid lip
interference. If lip does not lower to
trailer bed, reposition vehicle.
6. Ensure that truck bed supports
extended lip or the leveler frame
supports the ramp before driving on
ramp.
7. Stay clear of hinges and front and
sides of moving dock leveler.
8. Never use damaged or
malfunctioning dock leveler. Report
problems immediately to supervisor.
Maintenance/Service
1. Read and follow all instructions,
warnings and maintenance schedules
in the owner’s/user’s manual.
2. Maintenance/Service of dock leveler
restricted to trained personnel.
3. Place barriers on the driveway and on
dock floor to indicate service work is
being performed.
4. DO NOT ENTER PIT unless dock
leveler is securely supported by
maintenance prop.
5. If electrically powered turn off and use
OSHA lockout/tagout procedures.
DANGER
DO NOT
FORK THIS SIDE
FORK
HERE
CRUSH HAZARD
Do not work under dock leveler unless this maintenance prop has been secured in the
upright position. See owner’s/user’s manual for proper procedures. Failure to comply
will result in death or serious injury.
DANGER
1751-0788
CRUSH HAZARD
Open the pin latch and insert
through the maintenance
prop housing and prop
completely. Close the pin latch
to secure prop. Use every
time dock leveler is serviced.
Failure to comply will result
in death or serious injury.
DANGER
1751-0789
CRUSH HAZARD
DO NOT ENTER PIT unless dock leveler is
safely supported by maintenance prop. Place
barriers on driveway and dock floor to indicate
service work being performed. Refer to
owner’s/user’s manual for proper maintenance
procedures. Failure to comply will result in death
or serious injury.
DANGER
1751-0726
1751-0727
1751-0730 (x2)
1751-0788
1751-0789
1751-0726
CRUSH HAZARD
Do not remove main springs until leveler is safely supported by
maintenance prop. Main springs contain stored energy. Be sure
springs are fully unloaded and ends are loose before removal. Refer
to owner’s/user’s manual for proper maintenance procedure. Failure
to comply will result in death or serious injury.
DANGER
1751-0728
1751-0728
(decal placed in same position on both sides)
(decal placed in same position on both sides)
(decal placed in same position on both sides)
1751-0329 (x2)
1751-0330 (x2)

OWNER’S/USER’S RESPONSIBILITIES
64111-0006 — Sept 2010
1. The owner/ user should recognize the inherent dangers of the interface between the
loading dock and the transportation vehicle. The owner/ user should, therefore, train and
instruct all operators in the safe operation and use of the loading dock equipment in
accordance with manufacturer’s recommendations and industry standards. Before
operation of the equipment, all operators shall read, understand and be familiar with all
functions of equipment as described in the owner’s/user’s manual.
2. The manufacturer shall provide to the initial purchaser all necessary information with
regards to: Safety Information, Operation, Installation and Safety Precautions,
Recommended Initial and Periodic Inspections Procedures, Planned Maintenance
Schedule, Product Specifications, Troubleshooting Guide, Parts Break Down, Warranty
Information and Manufacturers Contact Information. The owner/ user shall be responsible
to verify that this information is available and received as well as proper instructions,
training and familiarity of the equipment for all operators has been completed. Owner’s/
User’s shall actively maintain, update and re train all operators on safe working habits and
operations of the equipment.
3. It is recommended when the transportation vehicle is positioned correctly in the dock
opening and in contact with both bumpers, there shall be a minimum of 4.00 inches
(100mm) overlap of the leveling device and the transportation vehicle at all times during
the loading and unloading process.
4. Name plates, placards, decals, instructions and posted warnings shall not be obscured
from the view of the operator or maintenance personnel for whom such warnings are
intended for. Contact manufacturer for any replacements.
5. Manufacturer’s recommended periodic maintenance and inspection procedures in effect at
the date of shipment shall be followed at all times. Written documentation of maintenance,
replacement parts or damage should be retained. In the event of damage notification to
the manufacturer is requested.
6. Any modifications or alterations of loading dock equipment shall only be done with prior
written approval from the original equipment manufacturer.
7. When industrial moving devices are being used in the loading or unloading of product
from the transportation vehicle, this vehicle shall have the brakes and wheel chocks
applied appropriately or all other positive restraining device shall be fully utilized.
8. Loading dock safety equipment should never be used outside of its intended use, range,
or capacity. Please consult the manufacturer if you have any questions as to the use,
range or capacity of the equipment.
9. When selecting loading dock safety equipment, it is important to consider not only present
requirements but also future plans and any possible adverse conditions, environments or
use.

INTRODUCTION
7
4111-0006 — Sept 2010
General Information
CM-Series dock levelers are available in the following
sizes, weight capacities, and options:
Width
6 ft (1828.8 mm)
6-1/2 ft (1981.2 mm)
7 ft (2133.6 mm)
Length
5 ft (1424 mm)
6 ft (1828.8 mm)
8 ft (2438 mm)
10 ft (3048 mm)
Capacity (CIR*)
25,000 lb (11 340 kg)
30,000 lb (13 608 kg)
*CIR (Comparative Industry Rating)
Call Poweramp for your specific needs.
Dock Leveler Stock Specifications
Congratulations on your choice of a Poweramp dock
leveler. This manual covers the CM-series
mechanical dock leveler.
Designed by Poweramp to be a marvel of simplicity
and efficiency, your dock leveler, when properly
installed, will provide many years of trouble-free
performance with an absolute minimum of
maintenance. To obtain maximum performance and
longest possible use, a simple program of preventive
maintenance is recommended.
Once again, thank you and congratulations on your
purchase of a Poweramp mechanical dock leveler.

INTRODUCTION
84111-0006 — Sept 2010
Component Identification
A—Lip
B—Lip Maintenance Prop
C—Platform
D—Lip Link
E—Lip Assist Spring
F —Platform Release Ring
G—Ratchet Pawl
H—Ratchet Bar
J —Pawl Spring
K—Main Frame
L— Platform Maintenance Prop
M—Hold-Down Mechanism
N—Safety Leg (2 used)
P —Lip (Snubber) Spring
Q—Lip Shock Absorber
R—Safety Leg Linkage
S—Safety Leg Release Ring
T— Lift Arm Assembly
U—Lift (Main) Spring
Assembly
A
E
C
BF
D
U
T
S
QR
NM
G
H
J
P
K
L

INSTALLATION
9
4111-0006 — Sept 2010
Prepare Pit
Before lowering the dock leveler into the pit, the
following must be performed:
1. Remove all debris from the pit and sweep the pit
clean.
2. Check the entire dock leveler pit for proper
construction according to approved/certified pit
drawings. Make sure pit is square by making the
following measurements:
• Measure pit width distance (A) at both front
and rear of pit.
• Measure dock floor-to-pit floor distance (B) at
all four corners.
• Measure pit length distance (C) at both sides.
• Measure corner-to-corner (criss-cross)
distance (D) at both sides. Take measurements
at dock floor level and at pit floor level.
If any measurement is off by more than 1/8 in.
(3.18 mm), contact Poweramp Technical Services
before proceeding.
A—Distance (Pit Width)
(Front and Rear)
B—Distance (Dock Floor-to-Pit
Floor) (All Four Corners)
C—Distance (Pit Length)
(Both Sides of Pit)
D—Distance (Pit Corner-to-Corner)
(Top, Bottom, and Both Sides)
IMPORTANT
IMPORTANT
DO NOT remove the shipping bands around the
dock leveler lip until instructed to do so.
Post safety warnings and barricade the work area
at dock level and ground level to prevent
unauthorized use of the dock leveler before
installation has been completed.
Failure to follow the installation instructions can
result in damage to dock leveler, the facilities,
and/or serious personal injury or death.
Only trained installation professionals with the
proper equipment should install this product.
B
A
D
C

INSTALLATION
10 4111-0006 — Sept 2010
Poweramp dock levelers are designed with
installation in mind. Each unit is shipped with lifting
brackets (A) fastened to the platform side joists.
Prepare Dock Leveler
A—Lifting Bracket (2 used) B—Shipping Bands
The dock leveler is heavy. Use a lifting device and
chains with the appropriate lifting capacity and
reach.
Always use the lifting brackets provided with the
unit whenever lowering or lifting a dock leveler into
or out of a pit.
Failure to follow these instructions may result in
damage to the dock leveler and/or serious personal
injury or death.
IMPORTANT
IMPORTANT
DO NOT remove the shipping bands (B) around
the platform lip and leveler frame at this time. The
shipping bands are needed to hold the leveler
together during the installation process.
A
B

INSTALLATION
11
4111-0006 — Sept 2010
1. Remove any bumpers that may be banded, or
bolted to the frame of the dock leveler.
DO NOT remove the shipping bands (B) around
the platform lip and leveler frame at this time.
NOTE: Overall width of platform and lifting brackets
(A) must be kept to a minimum to prevent
interference between the lifting brackets and
the pit walls as the dock leveler is lowered
into the pit.
2. Make sure the mounting hardware of lifting
brackets (A) is snug. The brackets should pivot
relatively freely on the mounting cap screw. DO
NOT over-tighten.
3. Attach lifting chains to lifting brackets (A) and to a
lifting device (i.e., hoist or fork truck) having the
appropriate lifting capacity and reach.
4. Remove wood blocks that are attached to the
leveler frame before putting the dock leveler into
the pit.
IMPORTANT
IMPORTANT
DO NOT over-tighten the lifting bracket hardware.
Over-tightening can damage the weather seal, if
equipped.

INSTALLATION
12 4111-0006 — Sept 2010
A
A—Distance (Leveler Frame
Height)
B—Shim Locations (Under
Rear Vertical Supports)
C—Shim Locations (Under
Lip Keepers and Prop)
D—Dock Floor
E—Rear Pit Curb Angle
F—String
G—Rear Hinge Frame Angle
H—Distance (Dock Floor-to-
Pit Floor)
J—Distance (Top of Shim
Stack-to-Dock Floor)
K—Shim Stack
L—Dock Leveler Frame
M—Pyramid (Preferred)
N—Stepped (Acceptable)
P—Offset (Not Acceptable)
Q—Straight (Not Acceptable)
Install Dock Leveler
M
N
P
Q
Shim
Stacking Methods
E
DF
K
G
L
J
H
BC
A

INSTALLATION
13
4111-0006 — Sept 2010
NOTE: Poweramp dock levelers are designed with a
nominal 1/2 in. (12.7 mm) shimming distance
to allow for pit inconsistencies.
1. Determine height of shim stack (K) for each shim
location (B) by performing the following:
a. Measure leveler frame height distance (A).
b. Measure dock floor-to-pit floor distance (H) at
each shim location (B). Write down the
dimensions obtained at each location.
c. Subtract distance (A) from distance (H) to
obtain the shim height. Repeat for each shim
location.
5. Using an appropriate lifting device connected to
the lifting brackets, lower dock leveler into the pit
so rear hinge frame angle (G) is tight against rear
pit curb angle (E) across full width of the leveler
frame.
6. Allow rear of dock leveler to rest on the rear shims
while keeping the front of the dock leveler level
with the dock floor.
7. Add shims at front shim locations (C) so front of
dock leveler will stay level with dock floor when
leveler is resting fully on shims.
4. Put a 1/4 in. (6.6 mm) thick shim at locations (C)
(under lip keepers/maintenance prop and safety
legs). Make sure shims are larger than frame
angle iron so pyramid or stepped stacking method
can be used.
NOTE: A 1/4 in. (6.6 mm) thick shim at locations (C)
is used only as a starting point. The final
shim stack height will be determined after the
dock leveler is lowered into the pit.
2. Using the results obtained in step 1, create the
individual shim stacks on the pit floor at locations
(B). Build each shim stack (K) using the pyramid
method (M) (preferred) or stepped method (N)
with the top shim having a minimum size of 4-1/2
x 4-1/2 in. (114.3 x 114.3 mm) and each
successive lower shim being larger so the shims
can be welded together using a fillet weld. DO
NOT use offset method (P) or straight method (Q).
NOTE: To assist in obtaining an accurate
measurement of distance (J), use a string (F)
pulled tight across the pit opening, directly
over the shim locations.
3. Verify that each shim stack is at the correct height
by measuring distance (J) [top of shim stack (K) to
dock floor]. Distance (J) must equal the dock
leveler height (A).
IMPORTANT
IMPORTANT
The minimum size of the shim that contacts the
leveler frame (i.e., the top shim of each shim stack)
must be at least 4-1/2 x 4-1/2 in. (114.3 x 114.3
mm) to support the full width of the frame rail and
to provide a shelf for a fillet weld.
Use the thickest shim stock possible for stability
and weld penetration purposes. DO NOT use
multiple layers of 1/8 in. (3.18 mm) or thinner shim
stock.
The dock leveler is heavy. Use chains and a lifting
device with the appropriate lifting capacity and
reach. Failure to do so may result in damage to
dock leveler and/or serious personal injury or
death.

INSTALLATION
14 4111-0006 — Sept 2010
A—Front of Dock Pit
B—Dock Leveler Frame
C—Side Pit Curb Angle
D—Gap [3/4 in. (19 mm)
Minimum]
E—Pry Locations
F—Rear Hinge Frame Angle
G—Rear Pit Curb Angle
H—Flare Bevel Weld, Typical
(To Fit Spacing)
8. With rear hinge frame angle (F) tight against rear
pit curb angle (G), perform/check the following:
• Pry between the platform and rear hinge frame
angle at locations (E) to make sure rear edge
of platform is parallel to the rear hinge frame
angle (F).
• Gap (D) must exist equally along both sides of
leveler so weather seal (if equipped) will not
bind during dock leveler operation.
9. If gap (D) cannot be obtained equally at both
sides of leveler, grind or add material at the rear
edge of rear hinge frame angle (F) as needed.
10. Allow the dock leveler to rest fully on the shim
stacks. Make sure the leveler is in the cross-
traffic (stored) position with lip resting on lip
keepers.
11. Check that a smooth and level transition exists
between the dock floor and the dock leveler
platform. Add or remove shims as necessary until
a smooth transition is obtained.
12. If leveler cannot be squared and made level as
instructed in steps 8 –10, contact Poweramp
Technical Services.
6in.
(152 mm)
3/8 in.
(9.5 mm)
GH
ABB
E
C
F
C
DD

INSTALLATION
15
4111-0006 — Sept 2010
14. Remove shipping bands at this time. Allow
platform to float. Add/Remove shims as
necessary to bring platform level/flush with floor.
17. Pull and hold the release ring (located in recess
at rear of platform) until the platform is fully
raised. Check for binding as platform rises.
18. Slowly walk out onto the platform to lower the
platform. Allow the platform to lower to the
cross-traffic position. Check for binding as
platform lowers.
19. If binding occurs, reposition leveler and/or add or
remove shims as necessary. Raise and lower
platform again. If platform still binds, contact
Poweramp Technical Services for further
instructions.
20. Check that the leveler is flush with the dock floor
and that the platform lip contacts both lip keepers
evenly.
NOTE: The illustration on the previous page shows a
typical weld pattern. The weld pattern will
vary slightly depending on size of dock
leveler.
13. With the rear hinge frame angle (F) tight against
the rear pit curb angle (G), weld the rear hinge
frame angle (F) to the rear pit curb angle (G)
using a 3/8 in. (9.5 mm) flare bevel skip weld
—each weld being 6 in. (152 mm) long.
Start at each end with a 6 in. (152 mm) long
weld. Space all the other welds out evenly
leaving approximately 6 in. (152 mm) space
between each weld.
Alternate welding locations to distribute heat.
Welding sequentially from one end to the other
may cause warping or distortion.
15. Weld front of dock leveler frame (B) to shims
located under the keepers, then weld the shims
to the front pit curb steel.
16. Disconnect lifting device and chains from the
lifting brackets.
Make sure all personnel are outside of the leveler
operating zone and stand clear of the platform lip
before removing the shipping bands. Failure to do
this may result in serious personal injury or death.
IMPORTANT
IMPORTANT
When activating the leveler, always pull AND hold
the platform release ring until the platform is at the
full-raised position. Releasing the ring while the
platform is still rising may result in damage to the
equipment.
IMPORTANT
IMPORTANT
Always ground welding equipment to the dock
leveler frame, NEVER to the platform.
DO NOT weld continuously along the full length of
the rear hinge frame angle. This can put
unnecessary stress on the leveler components,
causing the leveler not to function correctly and
shortening the lifespan of the affected components.
DO NOT grind or weld if hydraulic fluid or other
flammable liquid is present on the surface to be
ground or welded.
DO NOT grind or weld if uncontained hydraulic fluid
or other flammable liquid is present. Stray sparks
can ignite spills or leaks near the work area.
Always clean up the oil leaks and spills before
proceeding with grinding or welding.
Always keep a fire extinguisher of the proper type
nearby when grinding or welding.
Failure to follow these instructions may result in
serious personal injury or death.
Make sure all personnel are outside of the leveler
operating zone and clear of the platform lip before
activating the leveler. Failure to do this may result
in serious personal injury or death.

INSTALLATION
16 4111-0006 — Sept 2010
21. Pull the release ring to raise platform. Engage the
platform maintenance prop (B) in the service
(upright) position and lock the maintenance prop
at this position using an OSHA approved locking
device (D). Engage lip maintenance prop.
25. Remove the lifting brackets from the platform side
joists.
26. Disengage the platform maintenance prop.
27. Slowly walk out onto the platform to lower the
platform until it is at the cross-traffic (stored)
position.
28. Check operation of dock leveler by cycling the
leveler at least four times.
• When the platform is at full height, lip will be
fully extended.
• Lip will begin to drop after full height is
reached, taking approximately 12 seconds to
fully fold.
29. Check below-dock position by walking platform
down before lip folds completely.
• Lip will be over lip keepers.
• Platform safety legs will be resting on frame.
30. Check full below-dock position by walking the
platform down. Pull and hold safety leg chain (A)
before lip folds completely.
31. If the lip does not extend fully or lip folds too
quickly, see appropriate symptom in the
Troubleshooting section.
32. Install the dock bumpers as required.
22. Install shims under lift arm at locations (C) using
the pyramid shimming method. The lift arm pivot
must be solidly shimmed the entire length of the
lift arm pivot. Make sure the lift arm pivot is level
from side-to-side.
23. Finish weld all shims using a fillet weld.
• Weld all shims within each shim stack to each
other, then weld the shim stack to the leveler
frame.
• Weld the front leveler frame shim stacks to the
front pit curb steel if not done previously.
24. When all welding has been completed, remove all
slag then paint all the welds and shims.
A—Safety Leg Chain Pull Ring B—Platform Maintenance Prop C— Shim Location (Under Lift Arm Pivot) D—Prop Pin & Clip
Make sure the platform is properly supported in the
raised position before entering the pit to finish weld
the shims. Failure to do this may result in serious
personal injury or death.
B
D
A
C

OPERATION
17
4111-0006 — Sept 2010
Theory
The CM-series mechanical dock leveler uses large lift
springs (U) to apply force to lift arm (T). The lift arm
pushes against the underside of the platform (C),
rolling on the cam (not pictured) forcing the platform
to rise. The force of the spring tension is just enough
to lift the weight of the platform.
The ratchet pawl disengages only when the platform
release ring (F) is pulled AND held. Spring tension
from pawl spring (J) causes the ratchet pawl to
engage the ratchet bar when the release ring is let
go.
When the platform rises to approximately 2–3 inches
(51– 76 mm) from its full raised height, the snubber
spring (P) and a chain pulls the lip link (D) forward.
This, in conjunction with the lip assist spring (E),
causes the lip linkage to push the lip out and up. The
lip assist spring also helps control the amount of time
required for the lip to fully fold.
To lower the platform, the operator walks out onto the
platform. The platform will lower until the extended lip
rests on the truck bed. If the lip did not fully extend or
there is no truck at the dock, the platform will lower
until one of the following conditions occur:
• Lip is resting on lip keepers (cross-traffic position).
• Lip did not fully fold causing the platform to rest on
safety legs (below-dock position).
• Lip did not fully fold and safety legs are retracted,
causing the platform to rest on the safety stops (full
below-dock position).
The hold-down ratchet assembly will keep the
platform at the desired position until the platform
release ring is pulled again.
To actuate the dock leveler platform, the operator
pulls and holds the platform release ring (F) located
in the recess at the rear of the platform. This causes
ratchet pawl (G) to disengage from ratchet bar (H).
With the ratchet pawl disengaged, spring tension
from lift springs (U) forces the platform to rise.
NOTE: Ratchet pawl (G) and bar (H) are part of the
hold-down mechanism (M)
A—Lip
B—Lip Maintenance Prop
C—Platform
D—Lip Link
E—Lip Assist Spring
F—Platform Release Ring
G—Ratchet Pawl
H—Ratchet Bar
J —Pawl Spring
K—Main Frame
L— Platform Maintenance Prop
M—Hold-Down Mechanism
N—Safety Leg (2 used)
P—Lip Spring
Q—Shock Absorber
R—Safety Leg Linkage
S—Safety Leg Retract Pull Ring
T — Lift Arm
U—Lift Springs
IMPORTANT
IMPORTANT
When activating the leveler, always pull AND hold
the platform release ring until the platform is at the
full raised position. Releasing the ring while the
platform is still rising may result in damage to the
equipment.
A
E
C
BF
D
U
T
S
QR
N
M
G
H
J
P
K
L

OPERATION
18 4111-0006 — Sept 2010
Operating Instructions
The dock leveler operation instructions are
divided into the two methods of loading and
unloading:
• For ramp loading and unloading, see Ramp
Loading/Unloading Instructions on page 19.
• For end loading and unloading, see End
Loading/Unloading Instructions on page 20.
Stay clear of dock leveler when freight carrier is
entering or leaving dock area.
DO NOT raise or lower the dock leveler if anyone is
under or in front of leveler.
Keep hands and feet clear of pinch points. Avoid
putting any part of your body near moving parts.
Failure to follow these instructions may result in
severe personal injury or death.
The HM-series mechanical dock leveler is designed
to compensate for ± 12 in. (305 mm) of height
difference between the loading dock and the truck
bed. DO NOT use the dock leveler if the truck/trailer
bed is more than 12 in. (305 mm) higher or lower
than the dock floor.
DO NOT overload the dock leveler.
DO NOT operate any equipment while under the
influence of alcohol or drugs.
DO NOT leave/store equipment or material
unattended on the dock leveler.
Failure to follow these instructions may result in
personal injury and/or damage to equipment.
DO NOT activate the dock leveler until the
truck/trailer is positioned squarely against the
bumpers and the truck wheels are chocked.
Never remove the wheel chocks until loading and
unloading is finished and truck driver has been
given permission to leave.
DO NOT use the dock leveler if the freight carrier is
too high or too low.
NEVER use a fork truck or any other material
handling equipment to lower the dock leveler.
DO NOT drive any equipment onto the dock leveler
until platform lip is resting on the truck/trailer with
at least 4 in. (102 mm) of overlap.
Always maintain a safe distance from side edges of
leveler during the loading and unloading process.
NEVER attempt to walk on an unsupported lip.
NEVER allow untrained personnel to operate the
dock leveler.
NEVER attempt to lift any part of the leveler by
hand.
Failure to follow these instructions may result in
serious personal injury or death.
IMPORTANT
IMPORTANT
When activating the leveler, always pull AND hold
the platform release ring until the platform is at the
full-raised position. Releasing the ring while the
platform is still rising may result in damage to the
equipment.
12 in. (305 mm)
12 in. (305 mm)