Central Hydraulics 32879 Installation manual

20 TON SHOP PRESS
32879
SET UP AND OPERATING INSTRUCTIONS
Distributed exclusively by Harbor Freight Tools®.
3491 Mission Oaks Blvd., Camarillo, CA 93011
Visit our website at: http://www.harborfreight.com
Read this material before using this product.
Failure to do so can result in serious injury.
SAVE THIS MANUAL.
Copyright©2009 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. Diagrams within this manual may not be drawn proportionally. Due to continuing
improvements, actual product may differ slightly from the product described herein. Tools required for
assembly and service may not be included.
For technical questions or replacement parts, please call 1-800-444-3353.
Manual Revised 09g

Page 2 For technical questions, please call 1-800-444-3353. SKU 32879
SAVE THIS MANUAL
Keep this manual for the safety
warnings and precautions, assembly,
operating, inspection, maintenance and
cleaning procedures. Write the product’s
serial number in the back of the manual
near the assembly diagram (or month
and year of purchase if product has no
number). Keep this manual and the
receipt in a safe and dry place for future
reference.
IMPORTANT SAFETY
INFORMATION
In this manual, on the labeling,
and all other information
provided with this product:
This is the safety alert
symbol. It is used to alert
you to potential personal
injury hazards. Obey all
safety messages that
follow this symbol to avoid
possible injury or death.
DANGER indicates
a hazardous
situation which, if not
avoided, will result in death or
serious injury.
WARNING
indicates a
hazardous situation which, if
not avoided, could result in
death or serious injury.
CAUTION, used
with the safety
alert symbol, indicates a
hazardous situation which, if
not avoided, could result in
minor or moderate injury.
NOTICE is used to
address practices
not related to personal injury.
CAUTION, without
the safety alert
symbol, is used to address
practices not related to
personal injury.
WARNING Read all safety
warnings and instructions.
Failure to heed these markings
may result in personal injury
and/or property damage.
Save all warnings and
instructions for future
reference.
The warnings, precautions,
and instructions discussed
in this manual cannot cover
all possible conditions and
situations that may occur.
The operator must understand
that common sense and
caution are factors, which
cannot be built into this
product, but must be supplied
by the operator.
Work area
Keep the work area clean anda.
well lit. Cluttered benches and dark
areas increase the risks of electric
shock, re, and injury to persons.
Do not operate the tool inb.
explosive atmospheres, such
as in the presence of ammable
liquids, gases, or dust. Air and
hydraulic tools create sparks which
may ignite the dust or fumes.

Page 3
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SKU 32879
Personal safety
Stay alert. Watch what you area.
doing and use common sense
when operating the tool. Do not
use the tool while tired or under
the inuence of drugs, alcohol, or
medication. A moment of inattention
while operating the tool increases the
risk of injury to persons.
Dress properly. Do not wear looseb.
clothing or jewelry. Contain long
hair. Keep hair, clothing, and
gloves away from moving parts.
Loose clothes, jewelry, or long hair
increases the risk of injury to persons
as a result of being caught in moving
parts.
Do not overreach. Keep properc.
footing and balance at all times.
Proper footing and balance
enables better control of the tool in
unexpected situations.
Use safety equipment.d. Wear
heavy-duty work gloves during use.
Non-skid safety shoes and a hard
hat must be used for the applicable
conditions.
Always wear eye protection.e. Wear
ANSI-approved safety goggles,
heavy-duty work gloves, and steel-
toe work boots during set up and/or
use.
Tool use and care
Do not force the tool.a. Use the
correct tool for the application. The
correct tool will do the job better and
safer at the rate for which the tool is
designed.
Store the tool when it is idle outb.
of reach of children and other
untrained persons. A tool is
dangerous in the hands of untrained
users.
Check for misalignment or bindingc.
of moving parts, breakage of
parts, and any other condition
that affects the tool’s operation.
If damaged, have the tool serviced
before using. Many accidents are
caused by poorly maintained tools.
There is a risk of bursting if the tool is
damaged.
Use only accessories that ared.
identied by the manufacturer for
the specic tool model. Use of an
accessory not intended for use with
the specic tool model, increases the
risk of injury to persons.
Service
Tool service must be performeda.
only by qualied repair personnel.
When servicing a tool, use onlyb.
identical replacement parts. Use
only authorized parts.
Use only the lubricants suppliedc.
with the tool or specied by the
manufacturer.
Specic Safety Rules
Maintain labels and nameplates1.
on the Shop Press. These carry
important safety information. If
unreadable or missing, contact
Harbor Freight Tools for a
replacement.
Keep hands away from arbor plates2.
and press pin during use.

Page 4 For technical questions, please call 1-800-444-3353. SKU 32879
Do not move workpiece while3.
compressed.
Release load before service or4.
maintenance.
Bolt to oor before use.5.
Keep area under arbor plates clear.6.
If arbor plates rest on obstruction
(i.e., bolt, debris, etc.), it creates an
uneven press, causing excess stress
and possible breakage.
Do not stand directly in front of the7.
press when loaded. Do not leave the
press unattended when loaded.
Avoid off-center loads. Do not8.
operate if workpiece tilts or binds
during compression.
STOP and release compression9.
if you suspect imminent structural
failure. If safe, inspect thoroughly and
reposition before proceeding.
Do not compress springs or other10.
elastic objects. They could disengage
hazardously.
Keep bystanders out of work area.11.
20 Ton Limit. Do not operate the12.
hydraulic jack beyond rated capacity.
Inspect before every use; do not use13.
if parts are loose or damaged.
Jack service must be performed14.
only by qualied repair personnel.
Service or maintenance performed by
unqualied personnel could result in
a risk of injury.
When servicing a jack, use only 15.
identical replacement parts - refer to
attached, product-specic parts list
and diagram. Follow instructions in
the “Inspection, Maintenance, And
Cleaning” section of this manual.
Use of unauthorized parts or failure to
follow maintenance instructions may
create a risk of injury.
Only use with accessories rated to16.
handle the forces exerted by this tool
during operation. Other accessories
not designed for the forces generated
may break and forcefully launch
pieces.
Use only with bottle jack included 17.
with this press.
Industrial applications must follow18.
OSHA requirements.
This product is not a toy. Keep it out19.
of reach of children.
The warnings, precautions,20.
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.
SAVE THESE
INSTRUCTIONS.

Page 5
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SKU 32879
SPECIFICATIONS
Maximum
Capacity
20 Tons
(40,000 pounds)
Oil Type Hydraulic Oil
Note: For additional information regarding
the parts listed in the following pages,
refer to the Assembly Diagram near
the end of this manual.
Unpacking
When unpacking, make sure that the
item is intact and undamaged. If any parts
are missing or broken, please call Harbor
Freight Tools at 1-800-444-3353 as soon
as possible.
Components and Controls
Jack Plate (2)
Figure 1
Bottle Jack (14)
Arbor Plates (3)
Press Apron (5)
Press Frame (1)
OPERATING INSTRUCTIONS
Read the ENTIRE IMPORTANT
SAFETY INFORMATION
section at the beginning of this
manual including all text under
subheadings therein before set
up or use of this product.
Inspect tool before use, looking
for damaged, loose, and
missing parts. If any problems
are found, do not use tool until
repaired.
Components of this Shop Press
are heavy. You will need a
helper to safely assemble this
product.
Assembly
Using the Components photo (left)
and the Parts List and Diagram near
the end of the manual, lay out and
identify all pieces before assembly.
Have a helper stand the Press Frame
(1) upright and hold it steady until the
Feet (4) are secured in place.
Foot Bolt (9)
Press Frame (1)
Nut (12)
Foot (4)
Foot Bolt (9)
Figure 2
1. Slide each Foot (4) under the Press
Frame legs, lining up the bolt holes,
as shown above. Insert the Foot Bolts
(9) through the Press Frame (1) and
the Feet (4), then secure in place with
the Nuts (12).

Page 6 For technical questions, please call 1-800-444-3353. SKU 32879
Determine where you want to use2.
the Press and bolt it to the oor (See
Mounting to the Floor - page 7).
Figure 3 Pins (6)
Press Frame (1) Press Apron (5)
3. Slide the Pins (6) into the holes in the
Press Frame (1).
Note: For set-up, position the pins at least
several holes down from the top
holes in the Frame legs so you have
room to place the Jack Plate (2). You
can re-adjust the placement of the
Press Apron after assembly.
Angle the Press Apron (5) so the rails
of the Press Apron straddle the Legs
of the Press Frame, then lower into
place so the Press Apron rests on the
Pins.
Figure 4
Jack Plate (2)
Eye Bolts (8)
Nuts (11)
4. Insert the Eye Bolts (8) into the holes
in the Jack Plate (2) and secure in
place with the Nuts (11).
Figure 5
Arbor
Plate
(3)
Jack Plate (2)
Press Frame (1)
5. Place the Arbor Plates (3) on the
Press Apron.
Angle the Jack Plate (2) the same
way you placed the Press Apron and
slide it down the Press Frame so it
rests on the Arbor Plates.
Figure 6
Nuts (11)
Spring (7)
Spring
Bolts
(10)
Press Frame (1)
6. Insert the Spring Bolts (10) through
the top of the Press Frame (1) and
secure with the Nuts (11).
Hang the Springs (7) on the Spring
Bolts.

Page 7
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SKU 32879
Figure 7
Bottle
Jack
(14)
Springs (7)
Press Frame (1)
Eye Bolts (8)
Jack
Plate
(2)
7. Bleed the Bottle Jack (see Bleeding
the Bottle Jack section) and make
sure it is fully collapsed. Place the
Bottle Jack (14) on the center of the
Jack Plate (2). Slide the Jack Plate
up the Press Frame (1) so the Bottle
Jack Saddle ts in the bracket (center
underside of top of frame). Hook the
Springs (7) into the Eye Bolts (8) to
secure the Bottle Jack/Jack Plate in
place.
Mounting to the Floor
To mount the Shop Press, with1.
assistance, move the unit to the
location where it is to be used. If
needed, drill four 1/2” diameter
mounting holes in the feet and use as
a template to mark the spots where
four 1/2” diameter holes will be drilled
in the concrete or wood oor. Check
for any hidden wiring or cables and
adjust the location for the holes as
needed. Then, temporarily set the
Shop Press aside.
Use a masonry drill bit to drill the2.
four 1/2” diameter holes (about 3”-4”
deep) into the concrete. Make sure to
blow out the concrete dust from the
drilled holes. Insert lag screw anchors
(not included) into the holes.
Set the Shop Press back to the3.
location where it is to be used, and
align the four 1/2” diameter mounting
holes in its feet with the four pre-
drilled 1/2” holes in the concrete or
wood. Then use four minimum 3”
long, 1/2” diameter, concrete anchor
bolts or lag bolts (not included)
to secure the Shop Press to the
concrete or wood oor.
Bleeding the Bottle Jack
Plunger/
Fulcrum
Handle (15) Elevating
Screw
(some models)
Oil Fill Hole
Oil Filler
Plug
Valve
Release
Screw
Saddle
Figure 8
IMPORTANT! Before rst use, check
for proper hydraulic oil level in the
Jack. Then thoroughly test the Jack
for proper operation prior to its actual
use. If the Jack appears not to be
working properly, it may be necessary
to bleed its hydraulic system of
excess air. To bleed the Bottle Jack:
Remove the Oil Filler Plug. Insert1.
the slot on the lower portion
of the Handle over the Valve
Release Screw. Turn the Handle
counterclockwise to close the Valve
Release Screw.

Page 8 For technical questions, please call 1-800-444-3353. SKU 32879
Insert the Handle into the Plunger/2.
Fulcrum Assembly. Apply pressure
to the Saddle, and pump the Handle
quickly several times.
Check the Oil Fill Hole and, if3.
necessary, top off the Oil Fill Hole
with hydraulic oil.
Replace the Oil Filler Plug.4.
Test the Jack several times before5.
putting into use. If, after purging,
the Jack still does not appear to be
working properly, do not use the
Jack until it has been repaired by a
qualied service technician.
General Operating Instructions
The Shop Press can be used for
a variety of functions including
electric motor and armature
repair, installation and removal of
pressure tted parts such as gears
and bearings, and bending or
straightening of metal. Care should
be taken in set up and operation of
the Shop Press to avoid damage or
injury.
To operate the Shop Press:
Use the Pins (6) to adjust the height 1.
of the Press Apron (5).
Note: The Press Apron (5) should be in
the highest position possible with the
workpiece as close as possible to the
ram of the Jack Plate (2).
Place the item to press between the2.
Arbor Plates (3).
WARNING: Make sure there is no
obstruction (such as a stray bolt or
debris) under the Arbor Plates. Such
items create an uneven surface
which can cause the Arbor Plates to
break under pressure.
WARNING: When pressing two items
together, the items must be lined
up vertically. If not, one item may
forcefully eject itself sideways from
the unit.
Using the Jack Handle (15), jack 3.
down the Jack Plate until the ram
of the Jack Plate contacts your
workpiece. Make sure if you are
pressing two items together, that they
are in vertical alignment. Continue to
operate the Handle to press the work
piece.
When the task is completed, be4.
careful when releasing Jack pressure.
For safety, remove the Handle, then
use the Handle to slowly turn the
Valve Release Screw on the Jack,
allowing the Jack Plate to rise.
WARNING: After pressing, during the
release process the Jack may rise
quickly. Stay clear.

Page 9
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SKU 32879
USER-MAINTENANCE
INSTRUCTIONS
Procedures not specically
explained in this manual
must be performed only by a
qualied technician.
TO PREVENT
SERIOUS INJURY
FROM TOOL FAILURE:
Do not use damaged
equipment. If abnormal noise
or vibration occurs, have the
problem corrected before
further use.
Before each use,1. inspect the
general condition of the Shop Press
and Bottle Jack. Check for broken,
cracked, or bent parts, loose or
missing parts, and any condition that
may affect the proper operation of the
product. If a problem occurs, have
the problem corrected before further
use.
Do not use damaged equipment.
Before each use, thoroughly test2.
the Bottle Jack (14) for proper
operation prior to its actual use. If
the Bottle Jack appears not to be
working properly, follow Bleeding
the Bottle Jack instructions.
Change the hydraulic oil at least3.
once every three years. To change
the hydraulic oil:
With the Jack fully lowered, unhooka.
the Springs from the Eye Bolts and
remove the Jack from the Shop
Press.
Remove the Oil Filler Plug.b.
Tip the Bottle Jack to allow the oldc.
hydraulic oil to drain out of the unit
completely, and dispose of the old
hydraulic oil in accordance with local
regulations.
Completely ll the unit with a high d.
quality hydraulic oil (not included)
until the oil just begins to run out of
the Oil Fill Hole.
Reinstall the Oil Filler Plug.e.
Clean with a clean cloth using af.
detergent or mild solvent.
Replace the Bottle Jack onto theg.
Shop Press (See step 7 under
Assembly).

Page 10 For technical questions, please call 1-800-444-3353. SKU 32879
Troubleshooting
TO PREVENT SERIOUS INJURY:
Use caution when troubleshooting a malfunctioning jack.
Completely resolve all problems before use. If the solutions presented in the Troubleshooting guide do not solve the problem, have a qualied technician inspect and repair the jack before use. After the jack is repaired: Test it carefully without a load by raising it and lowering it fully, checking for proper operation, BEFORE RETURNING THE JACK TO OPERATION.
DO NOT USE A DAMAGED OR MALFUNCTIONING JACK!
POSSIBLE SYMPTOMS PROBABLE SOLUTION
(Make certain that the jack is not supporting a load while attempting a solution.)
Jack will not function at its weight capacity
Saddle lowers under load
Pump stroke feels spongy
Saddle will not lift all the way
Handle moves up when jack is under load
Oil leaking from ller plug
X X Check that Release Valve is closed fully. X X X
Valves may be blocked and may not close fully. To ush the valves:
Lower the Saddle and securely close the1. Release Valve. Manually lift the saddle several inches.2. Open the release valve and force the3. saddle down as quickly as possible.
XX X
Jack may be low on oil. Check the oil level and rell if needed. Jack may require bleeding - see instructions on page 7.
XUnit may have too much hydraulic oil inside,
check uid level and adjust if needed.

Page 11
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SKU 32879
PARTS LIST & ASSEMBLY DIAGRAM
10
6
7
15
8
11
3
9
9
412
12
41212
9
9
6
5
3
11
2
8
14
7
1
10
11
11
Part Description Qty
1 Press Frame 1
2 Jack Plate 1
3 Arbor Plate 2
4 Foot 2
5 Press Apron 1
6 Pin 2
7 Spring 2
Part Description Qty
8 Eye Bolt M8 2
9 Foot Bolt M12×25 4
10 Spring Bolt M8×38 2
11 Nut M8 4
12 Nut M12 4
14 Jack 1
15 Jack Handle 1
Record Product’s Serial Number Here:
Note: If product has no serial number, record month and year of purchase instead.
Note: Some parts are listed and shown for illustration purposes only, and are not
available individually as replacement parts.

Page 12 For technical questions, please call 1-800-444-3353. SKU 32879
LIMITED 90 DAY WARRANTY
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 90 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,
criminal activity, improper installation, normal wear and tear, 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 veries 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 specic 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]
PLEASE READ THE FOLLOWING CAREFULLY
THE MANUFACTURER AND/OR DISTRIBUTOR HAS PROVIDED THE PARTS LIST AND ASSEMBLY
DIAGRAM IN THIS MANUAL AS A REFERENCE TOOL ONLY. NEITHER THE MANUFACTURER OR
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 STATES THAT 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.