Central Hydraulics 94835 Parts list manual

Rolling Bridge Jack
6000 lb. Maximum Capacity
94835
ASSEMBLY AND OPERATION INSTRUCTIONS
Due to continuing improvements, actual product may differ slightly from the product described herein.
®
3491 Mission Oaks Blvd., Camarillo, CA 93011
Visit our website at: http://www.harborfreight.com
TO PREVENT SERIOUS INJURY, READ AND UNDERSTAND
ALL WARNINGS AND INSTRUCTIONS BEFORE USE.
Copyright©2006 by Harbor Freight Tools®. All rights reserved. No portion of this
manual or any artwork contained herein may be reproduced in any shape or form
without the express written consent of Harbor Freight Tools.
For technical questions or replacement parts, please call 1-800-444-3353.

SKU 94835 For technical questions please call 1-800-444-3353 Page 2
Specifications
Construction Formed and welded steel
Hydraulic Ram
Diameter 1-1/2”
Air Pressure Range 80 - 120 PSI
Air Inlet Thread 1/4” x 18 NPT
Overall Dimensions 55-3/8” L x 18-3/8” W x
23-1/4” H
Maximum Lift
Capacity 6000 lb. (3 Tons)
Vertical Travel 10.6”
Pump Actuation Foot Pedal
Roller Assembly
Width
Minimum: 39-1/2”
Maximum: 55-3/8”
Net Weight 302 lb.
NOTE: All part numbers mentioned in this manual refer to the Parts List on page
10 and the Assembly Diagram on page 11.
Intended Purpose of this Lift
This lift is designed to be used in conjunction with an automotive lift (not includ-
ed), or in a situation where guide rails have been installed in a shop floor. The
Roller Guides (19) may be adjusted to run on parallel steel tracks between 39-½”
and 55-3/8” apart. CAUTION: To prevent the Rolling Jack from coming off the
ends of the tracks or falling from the lift, appropriately sturdy stops must be placed
on all four ends of the tracks or rails on which this jack will be used.
Save This Manual
You will need the manual for the safety warnings and precautions, assembly
instructions, operating and maintenance procedures, parts list and diagram. Keep
your invoice with this manual. Write the invoice number on the inside of the front
cover. Keep the manual and invoice in a safe and dry place for future reference.
Safety Warnings and Precautions
WARNING: When using tool, basic safety precautions should always be fol-
lowed to reduce the risk of personal injury and damage to equipment.
Read all instructions before using this tool!
Keep work area clean. Cluttered areas invite injuries.
Observe work area conditions. Do not use machines or power tools in damp
or wet locations. Don’t expose to rain. Keep work area well lit.
Keep children away. Children must never be allowed in the work area. Do not
let them handle machines, tools, or extension cords.
Store idle equipment. When not in use, tools must be stored in a dry location
to inhibit rust. Always lock up tools and keep out of reach of children.
1.
2.
3.
4.

SKU 94835 For technical questions please call 1-800-444-3353 Page 3
Use the right tool for the job. Do not attempt to force a small tool or
attachment to do the work of a larger industrial tool. There are certain
applications for which this tool was designed. It will do the job better
and more safely at the rate for which it was intended. Do not modify this
tool and do not use this tool for a purpose for which it was not intended.
Dress properly. Do not wear loose clothing or jewelry as they can be caught
in moving parts. Protective, electrically non-conductive clothes and non-skid
footwear are recommended when working. Wear restrictive hair covering to
contain long hair.
Use eye and ear protection. Always wear ANSI approved impact safety goggles
when working. Wear a full face shield if you are producing metal filings or wood
chips. Wear an ANSI approved dust mask or respirator when working around
metal, wood, and chemical dusts and mists.
Do not overreach. Keep proper footing and balance at all times. Do not reach
over or across running machines.
Maintain tools with care. Keep tools maintained and clean for better and safer
performance. Follow instructions for lubricating and changing accessories. The
handles must be kept clean, dry, and free from oil and grease at all times.
Remove adjusting keys and wrenches. Check that keys and adjusting wrenches
are removed from the tool or machine work surface before beginning work.
Avoid unintentional operation. Be sure all safety precautions are followed, lift
is secure and vehicle is properly positioned before operating this jack. Always
think several steps ahead of your current operation to ensure safety.
Stay alert. Watch what you are doing, use common sense. Do not operate any
tool when you are tired or using any medication.
Check for damaged parts. Before using any tool, any part that appears dam-
aged should be carefully checked to determine that it will operate properly and
perform its intended function. Check for alignment and binding of moving parts;
any broken parts or mounting fixtures; noisy, loose or damaged roller guides
(19); and any other condition that may affect proper operation. Any part that is
damaged should be properly repaired or replaced by a qualified technician. Do
not use the tool if any control does not operate properly.
Replacement parts and accessories. When servicing, use only identical
replacement parts. Use of any other parts will void the warranty. Only use ac-
cessories intended for use with this tool. Approved parts and accessories are
available from Harbor Freight Tools.
Do not operate tool if under the influence of alcohol or drugs. Read warning
labels on prescriptions to determine if your judgment or reflexes are impaired
while taking drugs. If there is any doubt, do not operate the tool.
Maintenance. For your safety, service and maintenance should be performed
regularly by a qualified technician.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.

SKU 94835 For technical questions please call 1-800-444-3353 Page 4
The rails on which this jack will be used must be securely held in place
and perfectly level and parallel. If either end of the rails is loose, closer or
farther apart, higher or lower than the other, the jack could fall off the rails, bind
with the rails, move or tip causing property damage, SEVERE PERSONAL
INJURY OR DEATH. Due to the severe hazards created by improper rail setup,
the installation must be done by a qualified technician.
Use compressed air only. Never use any explosive gas or any other gas aside
from compressed air as an energy source.
Keep the air hose off the rails and away from the rollers at all times. If an
air hose is crushed, it can rupture resulting in personal injury.
This Rolling Bridge Jack may cause a tripping hazard if installed in the
floor of a workshop. Orange safety cones, a fence or other warning device
should be used to warn of a tripping hazard.
The Scissor Assembly may cause a pinch hazard. Use extreme caution to
prevent any person, animal or equipment from being pinched in the scissor as-
sembly during operation.
Do not exceed the weight limit of this jack, which is 6000 lb. (3 tons). Over-
loading may cause damage to the seals of the Foot Pedal Assembly (26) or
Hydraulic Ram (12). Overloading may also cause the jack to fade or suddenly
fail, allowing the vehicle to suddenly lower.
Never try to lift an unbalanced load. An unbalanced load may suddenly pitch
off the jack, causing serious injury or property damage.
Warning:The warnings, cautions, and instructions discussed in this instruction
manual cannot cover all possible conditions and situations that may occur.
It must be understood by the operator that common sense and caution are
factors which cannot be built into this product, but must be supplied by the
operator.
17.
18.
19.
20.
21.
22.
23.

SKU 94835 For technical questions please call 1-800-444-3353 Page 5
Unpacking
When unpacking, check for damage. If any parts are missing or broken, please
call Harbor Freight Tools at the number on the cover of this manual.
Assembly
Before initial use, this unit must first be installed on the automotive lift or rails (not
included) on which it will be used. A pressurized air supply must be furnished. The
hydraulic fluid level also must be checked before use.
Before Operating this Lift
Installing the Rolling Jack on your automotive lift or rails.
1. The Roller Guides (19) are effectively wheels which will operate on rails
much like the wheels on a railroad train. They will work on the edges of the
platforms of an automotive lift, or on rails mounted on a work shop floor.
2. WARNING: The automotive lift or rails on which this Rolling Jack will be
mounted must be level, solid and capable of supporting more than the
weight of this unit and any item that will be lifted by this jack. Serious
personal or property damage may occur if the support provided for this jack
fails during a lifting operation.
3. Loosen the four Bolts m10x25 (25). By pulling or pushing the Telescoping
Frames (21), adjust the spacing of the Roller Guides (19) to match the
spacing of your lift or rails. The Telescoping Frames (21) should be extended
about the same amount, keeping the Lower Frame (20) centered in the
assembly. Tighten the four Bolts m10x25 (25).
4. Place the Rolling Jack on your automotive lift or rails. Check its operation,
and adjust the spacing of the Telescoping Frames (20) if necessary.
5. Install adequately sturdy and strong stops (not included) on both ends of
each rail to ensure that the Rolling Jack cannot roll off the ends of the rails.

SKU 94835 For technical questions please call 1-800-444-3353 Page 6
Supplying Air Pressure to the Rolling Jack
Pressurized air supplied to the Foot Pedal / Hydraulic Pump Assembly (26)
is converted to hydraulic pressure. The hydraulic pressure passes through the
Hydraulic Hose (33) and activates the Hydraulic Ram (12). The Hydraulic Ram
activates the Scissor Assembly (15 and 16) which in turn lifts the Top Strut (10)
with its Saddles (3). This operation will lift your vehicle or other work item.
1. The Foot Pedal / Hydraulic Pump
Assembly (26) is supplied with a
male quick-release air adapter, as
shown in the photo.
2. Attach your air hose with a suitable
female quick-release air adapter
to this male adapter. Adjust your
air supply pressure to 90-120 PSI.
CAUTION: Do not exceed 120 PSI,
as this may damage the jack.
3. To operate the Rolling Bridge Jack,
press down on the lower portion of
the pedal marked “PUMP”.The jack
will begin to rise. To lower the jack, press on the portion of the pedal marked
“RELEASE”. The jack will begin to lower.
WARNING: Keep feet, hands any part of your body, any other person or
animal or any equipment away from the Scissor Assembly (15 and 16)
when raising or lowering this jack. Severe personal or property injury
may result from items being pinched in the scissors assembly or related
components during operation of this jack.
4. The air hose used should be of good quality, and in good condition.The air hose
should be routed to the jack in a way that will not cause a tripping hazard. The
air hose should not be allowed to be near the scissor assembly. The air hose
may be detached and put away when the Rolling Bridge Jack is not in use.
The Foot Pedal / Hydraulic
Pump Assembly (26)
male quick-release
air adapter
PUMP RELEASE

SKU 94835 For technical questions please call 1-800-444-3353 Page 7
Purging the Hydraulic Ram
NOTE: Before first using this tool, the hydraulic ram must be purged.
1. To purge the Ram, first raise the Jack to its uppermost position, with no load.
2. When the Jack has been raised, remove the Filler Bolt from the Hydraulic
Cylinder. Keeping your hands and tools clear, press the Foot Pedal down to
attempt to raise the jack even higher.
3. When it is clear the Jack will not raise any higher, release the Foot Pedal.
4. Add good quality hydraulic oil into the opening in the Cylinder where the
Filler Bolt has been removed. Fill until the Cylinder will hold no more oil.
5. Replace the Filler Bolt and its Seal Washer into the Cylinder, tighten firmly.
Lower the Jack by pressing the RELEASE portion of the Foot Pedal.
6. Check the condition of the Hydraulic Lift Table before each use. Raise and
lower it several times before adding any load. Be sure that all controls work
properly, and that it raises and lowers smoothly.
Operating the Rolling Bridge Jack
NOTICE: This jack is not to be used for any aircraft purpose.
1. Observing all safety precautions, drive the work vehicle over the Rolling Bridge
Jack. Shut off the engine, put the vehicle in gear or park, and set the parking
brake.
2. Connect your air hose to the male air quick-release adapter. Check that your
air pressure regulator is set between 90 and 120 PSI.
3. Roll the Jack along its rails until it is positioned properly under the vehicle.
4. Pull out each Adjustable Arm Assembly (4) to position the Lift Pad (1) where
desired under the vehicle. CAUTION: Check with the vehicle manufacturer to
determine approved lift points for each vehicle. Never attempt to lift a vehicle
using unapproved lift points, or if the lift points are damaged or weakened by
rust. Damaged or improper lift points may cause the vehicle to suddenly fall
off the jack potentially causing serious personal or property injury.

SKU 94835 For technical questions please call 1-800-444-3353 Page 8
5. Press the “PUMP” portion of the Pedal (26) to raise the Lift Pads (1) enough
to contact the lift points of the vehicle. Confirm that you have good contact in
the right spot. If necessary, lower the jack and adjust the position of the Lift
Pads before proceeding.
6. With the Lift Pads in the correct position, press the PUMP portion of the Foot
Pedal long enough to raise the vehicle approximately one inch, just enough
to take the weight of the vehicle on the jack. Check to be sure the load is
balanced, and that by further lifting there is no danger of damage to the
vehicle or to any nearby tools or property.
7. After ensuring that it is safe to do so, press the PUMP portion of the Foot
Pedal to raise the vehicle to the desired height.
8. Place safety jack stands (not included) under the vehicle to prevent the
vehicle falling in case the jack should lower unexpectedly.
WARNING: Never go under a raised vehicle unless there are safety jack
stands in place.
NOTE: This jack is intended for temporarily lifting and lowering a vehicle or
similar work load. It is not for storage or for transporting loads. Do not leave
an item on the jack for an extended period of time, damage to the jack or to
other property may result. Do not attempt to transport any load on this jack,
severe personal or property damage may result.
9. To lower the vehicle, first ensure that all persons, animals and property are
safely away from the vehicle. Be sure nothing is near the scissor assembly.
Remove the safety jack stands.
10. Lower the vehicle by pressing the “RELEASE” portion of the Pedal Assembly.
Control the speed of lowering to ensure safety and that the vehicle will rest
solidly on the ground.
11. With the vehicle safely on the ground, push the Adjustable Arms (4) back
into Top Strut (10).
12. Disconnect the air hose, and place the air hose clear of the vehicle.
13. Drive the vehicle off the Jack.

SKU 94835 For technical questions please call 1-800-444-3353 Page 9
Maintenance
1. Periodically check to be sure the Roller Guides are properly adjusted to the
track or rail on which the jack is mounted. Check to be sure the stops (not
included) at the ends of the rails are secure and in good condition. Check to
be sure the rails are secure, stable, parallel and level. Check to be sure the
Bolts m10x25 (25) are secure.
2. Periodically check the air and hydraulic fittings and Hydraulic Hose (33) for
leaks. Repair if any leak is detected.
3. Periodically lubricate all moving points of the Rolling Jack, including, but not
limited to Adjustable Arms (4), Roller Axle (7), Lower Axle (14), Flat Washer
(17), Roller Guide (19), Slider Shaft (22), Scissor Assembly Axle (30), and
Sleeve Bushings (34).
4. The piston of the Hydraulic Ram (12) should be kept clean, free of dirt and
water, and protected from corrosion.
Troubleshooting
1. If the jack fails to lift, or fades under load, check the air connection, hydraulic
connectors and Hydraulic Hose (33) for leaks.
2. If no leaks are detected, have a qualified service person inspect the Foot
Pedal / Hydraulic Pump Assembly (26) and Hydraulic Ram (12) for faults.

SKU 94835 For technical questions please call 1-800-444-3353 Page 10
Parts List
NOTE: Some parts are listed and shown for illustration purposes only and are not available
individually as replacement parts.
Part Description Q’ty
1 Lift Pad 2
2 Locknut M6 4
3 Saddle 2
4 Adjustable Arm Ass’y 2
5 Spring Pin Ø5 x 35 6
6 Washer 20 4
7 Roller Axle 1
8 Bolt M8 x 14 4
9 Nut M6 4
10 Top Strut 1
11 Split Pin 4x50 1
12 Cylinder Assembly 1
13 C-clip 15 2
14 Lower Shaft 1
15 Outer Scissor Arm 1
16 Inner Scissor Arm Ass’y 2
17 Washer 24 4
18 Spacer 2
19 Roller Guide 6
20 Lower Frame 1
Part Description Q’ty
21 Telescoping Frame 2
22 Slider Shaft 1
23 C-clip 20 4
24 Nut M10 4
25 Bolt M10 x 25 4
26 Foot Pedal Pump 1
27 C-clip 18 2
28 Safety Lock Ass’y 1
29 Lock pin 1
30 Scissor Ass’y Axle 1
31 Adapter 2
32 Linkage Rod 1
33 Hydraulic Hose 1
34 Sleeve Bushing 4
35 Bolt 4
36 Spring 4
37 Roller Bar 4
38 Linkage Rod 1
39 Bolt M6 x 12 4
PLEASE READ THE FOLLOWING CAREFULLY
THE MANUFACTURER AND/OR DISTRIBUTOR HAS PROVIDED THE PARTS DIAGRAM INTHIS
MANUAL AS A REFERENCE TOOL ONLY. NEITHERTHE MANUFACTURER NOR DISTRIBUTOR
MAKES ANY REPRESENTATION OR WARRANTY OF ANY KIND TO THE BUYER THAT HE
OR SHE IS QUALIFIED TO MAKE ANY REPAIRS TO THE PRODUCT OR THAT HE OR SHE IS
QUALIFIED TO REPLACE ANY PARTS OF THE PRODUCT. IN FACT, THE MANUFACTURER
AND/OR DISTRIBUTOR EXPRESSLY STATESTHAT ALL REPAIRS AND PARTS REPLACEMENTS
SHOULD BE UNDERTAKEN BY CERTIFIED AND LICENSED TECHNICIANS AND NOT BY THE
BUYER. THE BUYER ASSUMES ALL RISK AND LIABILITY ARISING OUT OF HIS OR HER
REPAIRS TO THE ORIGINAL PRODUCT OR REPLACEMENT PARTS THERETO, OR ARISING
OUT OF HIS OR HER INSTALLATION OF REPLACEMENT PARTS THERETO.

SKU 94835 For technical questions please call 1-800-444-3353 Page 11
Assembly Diagram
9
1
2
2
3
4
13
14
12
5
6
22
8
8
6
5
5
5
5
56
6
16 17
17
30
17
13
20
31
24
25
21
19
19
23
23
26
27
29
28
19
7
18
15
11
10
32
33
34
34
35
35
36
37
38
27
39

SKU 94835 For technical questions please call 1-800-444-3353 Page 12
Harbor Freight Tools Co. makes every effort to assure that its products meet high quality and durability standards,
and warrants to the original purchaser that this product is free from defects in materials and workmanship for
the period of ninety days from the date of purchase. This warranty does not apply to damage due directly or
indirectly, to misuse, abuse, negligence or accidents, repairs or alterations outside our facilities, or to lack of
maintenance.We shall in no event be liable for death, injuries to persons or property, or for incidental, contingent,
special or consequential damages arising from the use of our product. Some states do not allow the exclusion or
limitation of incidental or consequential damages, so the above limitation of exclusion may not apply to you. THIS
WARRANTY IS EXPRESSLY IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
THE WARRANTIES OF MERCHANTABILITY AND FITNESS.
To take advantage of this warranty, the product or part must be returned to us with transportation charges prepaid.
Proof of purchase date and an explanation of the complaint must accompany the merchandise. If our inspection
verifies the defect, we will either repair or replace the product at our election or we may elect to refund the purchase
price if we cannot readily and quickly provide you with a replacement. We will return repaired products at our
expense, but if we determine there is no defect, or that the defect resulted from causes not within the scope of
our warranty, then you must bear the cost of returning the product.
This warranty gives you specific legal rights and you may also have other rights which vary from state to state.
3491 Mission Oaks Blvd. • PO Box 6009 • Camarillo, CA 93011 • [phone]
Limited 90 day warranty