Central Pneumatic 66984 User manual

Revised Manual 11h
3/4” Heavy Duty Impact Wrench
66984 Air Impact Wrench
Read this material
before using this product.
Failure to do so
can result in serious injury.
SAVE THIS MANUAL.
When unpacking, make sure that the product is intact and undamaged.
If any parts are missing or broken, please call 1-800-444-3353 as soon as possible.
Visit our website at: http://www.harborfreight.com
Copyright©2011 by Harbor Freight Tools®. All rights reserved. No portion of this manual or any artwork contained herein may be repro-
duced 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.

SKU 66984 For technical questions, please call 1-800-444-3353. Page 2
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.
Safety Alert Symbol and Signal
Words
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.
IMPORTANT SAFETY
INSTRUCTIONS
INSTRUCTIONS PERTAINING
TO A RISK OF FIRE,
ELECTRIC SHOCK, OR
INJURY TO PERSONS
WARNING – When using tools, basic
precautions should always be
followed, including the following:
General
a. To reduce the risks of electric
shock, re, and injury to persons,
read all the instructions before
using the tool.
Work area
a. Keep the work area clean and well
lighted. Cluttered benches and dark
areas increase the risks of electric
shock, re, and injury to persons.
b. Do not operate the tool in
explosive atmospheres, such as in
the presence of ammable liquids,
gases, or dust. The tool is able to
create sparks resulting in the ignition
of the dust or fumes.
c. Keep bystanders, children, and
visitors away while operating the

SKU 66984 For technical questions, please call 1-800-444-3353. Page 3
tool. Distractions are able to result in
the loss of control of the tool.
Personal safety
a. Stay alert. Watch what you are
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.
b. Dress properly. Do not wear loose
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.
c. Avoid unintentional starting.
Be sure the switch is off before
connecting to the air supply. Do not
carry the tool with your nger on the
switch or connect the tool to the air
supply with the switch on.
d. Remove adjusting keys and
wrenches before turning the tool
on. A wrench or a key that is left
attached to a rotating part of the tool
increases the risk of personal injury.
e. Do not overreach. Keep proper
footing and balance at all times.
Proper footing and balance
enables better control of the tool in
unexpected situations.
f. Use safety equipment. A
dust mask, non-skid safety
shoes and a hard hat must
be used for the applicable
conditions. Wear heavy-duty work
gloves during use.
g. Always wear eye
protection. Wear ANSI-
approved safety goggles.
h. Always wear hearing
protection when using
the tool. Prolonged
exposure to high intensity
noise is able to cause hearing loss.
Tool use and care
a. Use clamps or another practical
way to secure and support the
workpiece to a stable platform.
Holding the work by hand or against
the body is unstable and is able to
lead to loss of control.
b. Do not force the tool. 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.
c. Do not use the tool if the switch
does not turn the tool on or off.
Any tool that cannot be controlled
with the switch is dangerous and
must be repaired.
d. Disconnect the tool from the
air source before making
any adjustments, changing
accessories, or storing the tool.
Such preventive safety measures
reduce the risk of starting the tool
unintentionally. Turn off and detach
the air supply, safely discharge any
residual air pressure, and release the
throttle and/or turn the switch to its off
position before leaving the work area.

SKU 66984 For technical questions, please call 1-800-444-3353. Page 4
e. Store the tool when it is idle out
of reach of children and other
untrained persons. A tool is
dangerous in the hands of untrained
users.
f. Maintain the tool with care. A
properly maintained tool is easier to
control.
g. Check for misalignment or binding
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.
h. Use only accessories that are
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
a. Tool service must be performed
only by qualied repair personnel.
b. When servicing a tool, use only
identical replacement parts. Use
only authorized parts.
c. Use only the lubricants supplied
with the tool or specied by the
manufacturer.
Air source
a. Never connect to an air
source that is capable of
exceeding 90 PSI. Over
pressurizing the tool may
cause bursting, abnormal operation,
breakage of the tool or serious injury
to persons. Use only clean, dry,
regulated compressed air at the rated
pressure or within the rated pressure
range as marked on the tool. Always
verify prior to using the tool that the
air source has been adjusted to the
rated air pressure or within the rated
air-pressure range.
b. Never use oxygen, carbon dioxide,
combustible gases or any bottled
gas as an air source for the tool.
Such gases are capable of explosion
and serious injury to persons.
SAVE THESE
INSTRUCTIONS.
SYMBOLS AND
SPECIFIC SAFETY
INSTRUCTIONS
Symbol Denitions
Symbol Property or statement
noNo-load speed
.../min Revolutions or reciprocation per
minute
PSI Pounds per square inch of pressure
ft-lb Foot-pounds of torque
BPM Blows per minute
CFM Cubic Feet per Minute ow
SCFM Cubic Feet per Minute ow at
standard conditions
NPT National pipe thread, tapered
Chart continued in next column.

SKU 66984 For technical questions, please call 1-800-444-3353. Page 5
Symbol Denitions
Symbol Property or statement
NPS National pipe thread, straight
WARNING marking concerning Risk
of Eye Injury. Wear ANSI-approved
eye protection.
WARNING marking concerning Risk
of Hearing Loss. Wear hearing
protection.
WARNING marking concerning Risk
of Respiratory Injury. Wear NIOSH-
approved dust mask/respirator.
WARNING marking concerning Risk
of Explosion.
Specic Safety Instructions
1. The warnings and precautions
discussed in this 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.
2. WARNING: The brass components
of this product contain lead, a
chemical known to the State of
California to cause birth defects (or
other reproductive harm). (California
Health & Safety code § 25249.5, et
seq.)
3. Only use with accessories rated to
handle the forces exerted by this tool
during operation. Other accessories
not designed for the forces generated
may break and forcefully launch
pieces.
4. Attach all accessories properly to the
tool before connecting the air supply.
A loose accessory may detach or
break during operation.
5. Obey the manual for the air
compressor used to power this tool.
6. Install an in-line shutoff valve to allow
immediate control over the air supply
in an emergency, even if a hose is
ruptured.
7. Use this tool with both hands only.
Using tools with only one hand can
result in loss of control.
8. Do not lay the tool down until it has
come to a complete stop. Moving
parts can grab the surface and pull
the tool out of your control.
Vibration Precautions
This tool vibrates during use.
Repeated or long-term exposure to
vibration may cause temporary or
permanent physical injury, particularly to
the hands, arms and shoulders. To reduce
the risk of vibration-related injury:
1. Anyone using vibrating tools regularly
or for an extended period should
rst be examined by a doctor and
then have regular medical check-
ups to ensure medical problems are
not being caused or worsened from
use. Pregnant women or people
who have impaired blood circulation
to the hand, past hand injuries,
nervous system disorders, diabetes,
or Raynaud’s Disease should not use
this tool. If you feel any symptoms
related to vibration (such as tingling,
numbness, and white or blue ngers),
seek medical advice as soon as
possible.
2. Do not smoke during use. Nicotine
reduces the blood supply to the