MAG TOOLS JS300A Instructions for use

Hydraulic
Service Jack
w/ Air Motor
Printed in PRC
JS300A-M1 rev 04/08
Read this manual and follow all the Safety Rules and Operating Instructions before using this product.
Model
JS300A
Capacity
3 Ton
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.
!
!ADVERTENCIA
• Leer, comprender, y seguir las instrucciónes antes
de utilizar el aparato.
• El manual de instrucciónes y la información de
seguridad deben estar comunicado en lengua del
operador antes del uso.
• No seguir estas indicaciónes puede causar daños
personales o materiales.
!WARNING
To avoid crushing and related injuries:
NEVER work on, under or around a
load supported only by a hydraulic
jack. ALWAYS use adequately rated
jack stands.
Operating Instructions & Parts Manual
U.S. Patent No’s. 5,341,723
MAC TOOLS INC.
505 N. Cleveland Ave. Suite 200
Westerville, OH 43082

2
Before Use
1. Verify that the product and application
are compatible, if in doubt call Tech Service:
1-800-MAC-TOOL (622-8665).
2. Before using this product, read the operator's
manual completely and familiarize yourself thoroughly
with the product, its components and recognize the
hazards associated with its use.
3. To familiarize yourself with basic operation, locate
and turn the release valve (handle):
a. Clockwise until rm resistance is felt to further
turning. This is the ‘CLOSED’ release valve
position used to raise the saddle.
b. Counter-clockwise, but no more than 1/2 turn
from the closed position. This is the ‘OPEN’
release valve position used to lower the saddle.
4. With saddle fully lowered, remove the oil ller plug.
Pump 6 to 8 full strokes. This will help release any
pressurized air which may be trapped within the
reservoir. Check oil level. Fill until oil nearly covers
the inner cylinder as seen from the oil ller hole.
Reinstall the oil ller plug. See page 4, Maintenance
Section for details.
5. Pour a teaspoon of good quality, air tool lubricant
into the air supply inlet of the lift control valve.
Connect to air supply and operate for 3 seconds to
evenly distribute lubricant.
6. This product is equipped with the popular 1/4" NPT
air coupler. When installing a different air coupler of
your choice, ensure that thread tape or compound
is used when servicing connections. To ensure
dependable, trouble free operation an inline air dryer
and oiler is recommended.
7. Ensure that jack rolls freely. Raise and lower the
unloaded saddle throughout the lifting range before
putting into service to ensure the pump operates
smoothly. Replace worn or damaged parts and
assemblies with authorized replacement parts only.
Bleeding / Venting Trapped Air
With the release valve in the OPEN position (3b.) and
with saddle fully lowered, locate and remove the oil ller
plug. Pump 6 to 8 full strokes. This will help release
any pressurized air which may be trapped within the
reservoir. Reinstall the oil ller plug.
SAFETY and GENERAL
INFORMATION
Save these instructions. For your safety, read,
understand, and follow the information provided with
and on this jack before using. The owner and operator
of this equipment shall have an understanding of this
jack and safe operating procedures before attempting
to use. The owner and operator shall be aware that use
and repair of this product may require special skills and
knowledge. Instructions and safety information shall be
conveyed in the operator's native language before use
of this jack is authorized. If any doubt exists as to the
safe and proper use of this jack, remove from service
immediately.
Inspect before each use. Do not use if broken, bent,
cracked or damaged parts are noted. Any jack that
appears damaged in any way, or operates abnormally
shall be removed from service immediately. If the jack
has been or suspected to have been subjected to a
shock load (a load dropped suddenly, unexpectedly
upon it), immediately discontinue use until jack has been
checked by a factory authorized service center (contact
distributor or manufacturer for list of authorized service
centers). It is recommended that an annual inspection
be done by qualied personnel. Labels and Operator's
Manuals are available from manufacturer.
!
PREPARATION Assembly (see Fig. 2, 3)
1. Assemble the 2-piece handle with provided bolt.
2. Insert handle into the handle sleeve. Tighten the
bolt on handle sleeve to prevent accidental removal
of handle while in use.
PRODUCT DESCRIPTION
This Air/Lever actuated Hydraulic Service Jack is
designed to lift, but not support, one end of a vehicle.
Immediately after lifting, loads must be supported by a
pair of appropriately rated jack stands. It can be pumped
manually or connected to shop air capable of providing
7.8 CFM @ 150 psi (required for rated capacity lifts).
NEVER use a hydraulic jack as a stand
alone device. After lifting, immediately
support the lifted vehicle with a pair of appropriately
rated jack stands. NEVER place ANY portion of your
body beneath the vehicle when lifting OR lowering!
SPECIFICATIONS
Model Capacity Jack Size (L x W x H) Min.
Height
Max.
Height
Saddle
Dia.
Volume of
Hyd. Oil
JS300A 3 Ton 30” x 14 5/8” x 6 3/8” 5 1/4” 19” 5” 200 ml

Figure 1 - JS300A Nomenclature
3
OPERATION
Lifting
Only attachments and/or adapters supplied
by the manufacturer shall be used. Lift only
on area of the vehicle as specied by the vehicle
manufacturer.
!
To avoid crushing and related injuries:
• Never work on, under or around a load supported
only by hydraulic jack.
• Always use adequately rated jack stands.
• Chock each unlifted tire in both directions.
• Do not use this device to lift, level, lower, support nor
move a house, mobile home, travel trailer, camper or
any building structure.
• Be alert and sober when using this product. Do not
operate under the inuence of drugs or alcohol.
!WARNING
X
!WARNING
• Study, understand, and follow all printed materials
provided with/on this product before use.
• Do not exceed rated capacity.
• This is a lifting device only!
• Immediately after lifting, support the load with
a pair of appropriately rated jack stands.
• Use only on hard, level surface.
• Do not use adapters or accessories that are not
provided initially.
• Lift only on areas of the vehicle as specied by the
vehicle manufacturer.
• Never wire, clamp or otherwise disable the lift
control valve to function by other than operator's
hand.
• Do not move or dolly loads with this device.
• No alterations shall be made to this product.
• Failure to heed these markings may result in
personal injury and/or property damage.
rear caster
front wheel
saddle
air control
valve
handle sleeve
oil ller plug (on reservoir,
not shown)
pump piston
release valve / pump handle
air hose
bolt securing
handle to sleeve
Be sure all tools and personnel are clear
before lowering load. Slowly open the
release valve! The more you turn the handle counter-
clockwise, the faster the load will come down. Maintain
control of the rate of speed at which the load lowers
at all times!
1. Raise load high enough to clear the jack stands.
2. Remove jack stands carefully (always used in pairs).
3. Slowly turn the handle counter-clockwise, but no
more than 1/2 full turn. If the load fails to lower:
a. Use another jack to raise the vehicle high
enough to reinstall jack stands.
b. Remove the malfunctioning jack and then the
jack stands.
c. Use the functioning jack to lower the vehicle.
4. After removing jack from under the vehicle, fully
lower the saddle to reduce ram exposure to rust and
contamination.
!
Lowering
NEVER use hydraulic jack as a stand
alone device! ALWAYS transfer the lifted load
IMMEDIATELY to a pair of appropriately rated jack
stands. Use one pair of jack stands per vehicle.
Rated capacity is per pair only! Do not exceed rated
capacity.
!
1. Follow the vehicle manufacturer’s recommended
guidelines for lifting. Engage the emergency brake
and chock each unlifted wheel in both directions to
prevent inadvertent vehicle movement.
2. Close the release valve by turning the handle clockwise
until rm resistance is felt.
3. Refer to the vehicle manufacturer owner’s manual to
locate approved lifting points on the vehicle. Center
jack saddle under lift point.
4. Verify lift point, then pump handle to contact lift point.
To lift, pump handle or squeeze lift control valve until
load reaches desired height. Release grip on lift
control valve to stop lifting if using air function.
5. Transfer the load immediately to appropriately rated
jack stands.
NOTICE: NEVER operate air motor and pump
handle simultaneously! Doing so will not increase the
lifting capacity of the device and will likely damage
the hydraulic unit.

4
Use only Mobil DTE 13M or equivalent
hydraulic jack oil. Improper fluid can cause
premature failure of the jack and the potential for sudden
and immediate loss of load.
TROUBLESHOOTING
Symptom Possible Causes Corrective Action
Jack will not lift load • Release valve not tightly closed
• Load is too heavy
• Ensure release valve tightly closed
• Consider higher capacity jack
Jack will lift, but not maintain
pressure
•Release valve not tightly closed
• Hydraulic unit malfunction
•Ensure release valve tightly closed
• Discontinue use, contact Mac Tool
Technical Service
Jack will not lower after unloading • Reservoir overlled
• Linkages binding
• Drain uid to proper level
• Clean and lubricate moving parts
Poor lift performance • Fluid level low
•Air trapped in system
• Ensure proper uid level
•With ram fully retracted, remove oil
ller plug/screw to let pressurized
air escape. Reinstall oil ller plug
Will not lift to full extension • Fluid level low • Ensure proper uid level
Lubrication
A periodic coating of light lubricating oil to pivot points,
axles and hinges will help to prevent rust and assure that
wheels, casters and pump assemblies move freely.
Cleaning
Periodically check the pump piston and ram for signs
of rust or corrosion. Clean as needed and wipe with
an oily cloth.
Note: Never use sandpaper or abrasive material on
these surfaces!
Storage
When not in use, store the jack with saddle fully
lowered.
1. With saddle fully lowered set jack in its upright, level
position. Remove oil ller plug.
2. *Fill until oil nearly covers the inner cylinder as seen
from the oil ller hole. Reinstall the oil ller plug.
Changing oil
For best performance and longest life, replace the
complete uid supply at least once per year.
1. With saddle fully lowered, remove the oil ller plug.
2. Lay the jack on its side and drain the uid into a
suitable container.
Note. Dispose of hydraulic uid in accordance with
local regulations.
3. *Fill until oil nearly covers the inner cylinder as seen
from the oil ller hole. Reinstall the oil ller plug.
!
It is difcult to conrm the correct oil level by simply
looking into the oil reservoir after removing the oil ller
plug. *Correct oil level allows the saddle to reach its
advertised maximum height and its advertised minimum
height.
Too much oil will not allow the saddle to lower
completely.
Too little oil will not allow the saddle to raise
completely.
MAINTENANCE
Adding oil
•
•
REPLACEMENT PARTS
(refer to page 5, 6) Not all components of the jack are
replacement items, but are illustrated as a convenient
reference of location and position in the assembly
sequence. When ordering parts, give Model number,
part number and description below. Call or write for
current pricing: Mac Tools Inc. 505 N. Cleveland Ave.
Suite 200, Westerville, OH 43082.
Tel: 1-800-MAC-TOOL (622-8665)

Figure 2 - Replacement Parts Illustration for JS300A
Replacement Parts Illustration for JS300A
5

Replacement Parts List for model JS300A
**Seal Kit Contents:
6
Item Part No. for JS300A Description Qty
15905-00100-100 Oil Filler Plug 1
2 G931-07014-100 Pump Piston 1
3 G931-08003-000 Release Valve Connecting Bar 1
4G931-08002-000 Release Valve Gear 1
5 5206-00010-000 Nut M10 1
6 5303-00010-000 Lock Washer f10 1
7 5102-10016-000 Bolt M10x16 1
8 G931-00009-000 Return Spring, Handle Fork 1
9G070-00008-100 Pin 1
10 G070-05001-000 Handle Fork 1
11 G931-00003-000 Return Spring 2
12 G93P-01000-000 Saddle 1
13 G934-00003-000 Handle Fork Bolt, Left 1
14 G931-00011-000 Handle Fork Bolt, Right 1
15 5303-00020-000 Lock Washer f20 2
16 G931-00010-000 Bolt M12 4
17 5301-00020-000 Washer f18 2
18 5305-00015-000 E-Ring 2
19 G890-04100-100 Release Valve 1
20 G831-04000-000 Handle Assembly 1
21 G520-90026-K02 Caster Assembly 2
22 G890-90037-K01-04 Front Wheel Assembly 2
23 G83X-90010-K01 Hydraulic Power Unit 1
24 G831-03200-000
25 G831-03400-000
26 G831-00001-000 Cover Plate 1
27 G831-03500-000
Item Description Qty.
1 Oil Filler Plug 1
A O-Ring 2
BO-Ring 1
CRam Bearing 1
DBack-up Washer 1
EU-Cup 1
(**) Replacement requires special skills, knowledge, and equipment. Only an authorized service center
may perform the repair and/or replacement of these items. Contact Mac Tool Technical Service for list of
service centers.
28
Air Motor
Air Hose Assy.
Air Inlet Swivel
Quick Coupler-Male
F O-ring 1
G Washer 1
H Back-up Ring 1
I O-Ring 1
JBack-up Ring 1
KO-Ring 1
Item Description Qty.
JS300A-L0
JS300A-M0
Label (s)
Manual
1
1
1
1
1
-
-
-
29
31
32
Lift Control Valve
Seal Kit (includes #1, A~K)
30 G83X-90038-K01
A20060-0007
A20060-0016

7
ONE YEAR LIMITED WARRANTY
For a period of one (1) year from date of purchase, Mac Tools Inc. will repair or replace, at its option, without
charge, any of its products, which fails due to a defect in material or workmanship under normal usage. This limited
warranty is a consumer's exclusive remedy.
Performance of any obligation under this warranty may be obtained by returning the warranted product,
freight prepaid, to Mac Tools Inc. Warranty Service Department, 505 N. Cleveland Ave. Suite 200 Westerville, OH
43082.
Except where such limitations and exclusions are specically prohibited by applicable law, (1) THE
CONSUMER'S SOLE AND EXCLUSIVE REMEDY SHALL BE THE REPAIR OR REPLACEMENT OF DEFECTIVE
PRODUCTS AS DESCRIBED ABOVE. (2) Mac Tools Inc. SHALL NOT BE LIABLE FOR ANY CONSEQUENTIAL
OR INCIDENTAL DAMAGE OR LOSS WHATSOEVER. (3) ANY IMPLIED WARRANTIES, INCLUDING WITHOUT
LIMITATION THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE, SHALL BE LIMITED TO ONE YEAR, OTHERWISE THE REPAIR, REPLACEMENT OR REFUND AS
PROVIDED UNDER THIS EXPRESS LIMITED WARRANTY IS THE EXCLUSIVE REMEDY OF THE CONSUMER,
AND IS PROVIDED IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR IMPLIED. (4) ANY MODIFICATION,
ALTERATION, ABUSE, UNAUTHORIZED SERVICE OR ORNAMENTAL DESIGN VOIDS THIS WARRANTY AND
IS NOT COVERED BY THIS WARRANTY.
Some states do not allow limitations on how long an implied warranty lasts, so the above limitation may not
apply to you. Some states do not allow the exclusion or limitation of incidental or consequential damages, so the
above limitation or exclusion may not apply to you. This warranty gives you specic legal rights, and you may also
have other rights, which vary from state to state.
Mac Tools Inc.
505 N. Cleveland Ave. Suite 200 Westerville, OH 43082. U.S.A.