Central Pneumatic 92427 User manual

1” AIR IMPACT WRENCH
ASSEMBLY and OPERATING
INSTRUCTIONS
3491 Mission Oaks Blvd., Camarillo, CA 93011
Visit ourWeb site at http://www.harborfreight.com
For technical questions and replacement parts,please call 1-800-444-3353
Model 92427
®
Copyright © 2004 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.
TO PREVENT SERIOUS INJURY,
READ AND UNDERSTAND ALL WARNINGS
AND INSTRUCTIONS BEFORE USE.
®

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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 followed to
reduce the risk of personal injury and damage to equipment.
Read all instructions before using this tool!
1. Keep work area clean. Cluttered areas invite injuries.
2. 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 lighted. Do not use electrically
powered tools in the presence of flammable gases or liquids.
3. Keep children away. Children must never be allowed in the work area. Do not let
them handle machines, tools, extension cords, or air hoses.
4. 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.
5. 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.
6. Dress properly. Do not wear loose clothing or jewelry as they can be caught in
moving parts. Protective, electrically nonconductive clothes and nonskid footwear are
recommended when working. Wear restrictive hair covering to contain long hair.
Specifications
Maximum Torque 1450 Ft. Lbs.
Drive Size 1”
Air Inlet 1/2” - 14 NPT
Recommended Air Pressure 90 PSI
Maximum Air Pressure 120 PSI
Blows Per Minute 800
Air Consumption 12 CFM
Tool Weight 27.7 Lbs.
Impact Mechanism Twin Hammer

Page 3SKU 92427 For technical questions, please call 1-800-444-3353
7. Use eye and ear protection. Always wear ANSI approved impact safety goggles.
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.
8. Do not overreach. Keep proper footing and balance at all times. Do not reach over
or across running machines or air hoses.
9. Maintain tools with care. Keep tools clean for better and safer performance. Follow
instructions for lubricating and changing accessories. Inspect tool cords and air hoses
periodically and, if damaged, have them repaired by an authorized technician.The
handles must be kept clean, dry, and free from oil and grease at all times.
10. Disconnect air supply. Disconnect air hose when not in use.
11. Remove adjusting keys and wrenches. Check that keys and adjusting wrenches
are removed from the tool or machine work surface before plugging it in.
12. Avoid unintentional starting. Be sure the switch is in the Off position when not in
use and before plugging in. Do not carry any tool with your finger on the trigger,
whether it is plugged in or not.
13. Stay alert. Watch what you are doing, use common sense. Do not operate any tool
when you are tired.
14. Check for damaged parts. Before using any tool, any part that appears damaged
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; 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 switch does not turn On and Off properly.
15. Guard against electric shock. Prevent body contact with grounded surfaces such as
pipes, radiators, ranges, and refrigerator enclosures.
16. Replacement parts and accessories. When servicing, use only identical
replacement parts. Use of any other parts will void the warranty. Only use accessories
intended for use with this tool. Approved accessories are available from Harbor
Freight Tools.
17. Do not operate tool if under the influence of alcohol or drugs. Read warning
labels if taking prescription medicine to determine if your judgement or reflexes are
impaired while taking drugs. If there is any doubt, do not operate the tool.
18. Use proper size and type extension cord. If an extension cord is required, it must
be of the proper size and type to supply the correct current to the compressor without
heating up. Otherwise, the extension cord could melt and catch fire, or cause
electrical damage to the tool. Check your air compressor’s manual for the appropriate
size cord.
19. Maintenance. For your safety, maintenance should be performed regularly by a
qualified technician.
20. Compressed air only. Never use combustible gas as a power source.

Page 4SKU 92427 For technical questions, please call 1-800-444-3353
21. This ImpactWrench should only be used with impact sockets and extensions.
Using any other accessories can cause the accessories to break, causing permanent
damage to the unit and severe injury to the operator.
Note: Performance of the compressor (if powered by line voltage) may vary depending
on variations in local line voltage. Extension cord usage may also affect tool perfor-
mance.
Warning:The warnings,cautions,and instructions discussed in this instruction manual
cannot cover all possible conditions and situations that may occur. It must be under-
stood by the operator that common sense and caution are factors which cannot be
built into this product, but must be supplied by the operator.
Unpacking
When unpacking, check to make sure the parts listed on page 8 are included. If any parts
are missing or broken, please call Harbor Freight Tools at the number on the cover of this
manual as soon as possible.
For best service you should incorporate an oiler, regulator, and inline filter, as shown in the
diagram above. Hoses, couplers, oilers, regulators, and filters are all available at Harbor
Freight Tools.
1. You will need to prepare a 1/2” air connector (not included) to connect to the Air Inlet
(23) on the ImpactWrench. First, wrap the 1/2”air connector with pipe thread seal tape
before threading it into the Air Inlet (23). Connect the 3/8”ID air source hose to a quick
connect coupler, and then to the Impact Wrench.
Note: If you are not using an automatic oiler system, before operation, add a few
drops of PneumaticTool Oil to the airline connection. Add a few drops more after each
hour of continual use.
2. Set the air pressure on the regulator. Note:To achieve the maximum torque of 1450 Ft.
Lbs., set the air pressure at 120 PSI. Never exceed 120 PSI.
3. Check the air connection for leaks. Disconnect from the air source.
Impact
Wrench
Air Connection

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Assembly
1. Place the Handle (48) into the handle slot and secure it with two Screws (49). See
FIGURE 1.
FIGURE 1
Operation
Warning!! This ImpactWrench supplies powerful torque and is designed to be operated with
two hands. Failure to operate the Impact Wrench with two hands may result in serious,
permanent injury. See FIGURE 3 below.
Securing with the
two Screws (49)
Trigger (21)
Air Inlet (23)
Forward/Reverse Valve (34)
Air Coupler
Wrench (54)
Anvil (43)
Handle (48)
FIGURE 2
Proper way
to hold the
Impact Wrench
FIGURE 3

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Operation (continued)
Refer to FIGURES 2 and 4, and the Assembly Drawing on page 9.
Note: Turn off your air compressor and disconnect the air hose when you are changing
sockets. After you attach the socket, attach the air hose and turn the air compressor
on.
1. Select the appropriate size 1” drive socket for your needs.
2. Push and snap the socket (not included) onto the Anvil (43).
3. To operate the Forward/Reverse Valve (34) follow the directions in FIGURE 5 below.
Tightening
Note: Set the Forward/Reverse Valve (34) so that the anvil turns clockwise (forward).
4. Tighten the nut as tight as you can by hand.
5. Place the socket (not included) over the nut you wish to tighten.
6. Grip the Impact Wrench firmly with two hands and gently squeeze the Trigger (21).
Note: If the Impact Wrench cannot tighten the nut to your satisfaction, do not raise the air
pressure on the compressor over 120 PSI. Pressures above 120 PSI will strip the
workpiece and damage the tool, potentially causing the tool to fail, causing serious
injury. Use other appropriate methods and tools to tighten the nut.
7. When the nut is tightened, release the Trigger (21). Turn off the air compressor and
disconnect the hose.
8. Always check the recommended torque specification for the nut. Use a torque
wrench to tighten the nut to the proper setting after using the Impact Wrench.
FIGURE 4
Reverse
(loosening)
Forward
(tightening)
Note: On the bottom of the Forward/Reverse Valve (34) there are
markingsonthe valve thatshowwhat direction theForward/Reverse
Valve (34) is set to. If the bottom valve is turned in the “Off” arrow’s
direction, then the Impact Wrench is set to take off bolts. If the bot-
tom valve is turned in the “On” arrow’s direction, then the Forward/
ReverseValve (34) is set to tighten on bolts.
FIGURE 5
ON
OFF
Oil Screw
(22)
REV 11/04

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Operation (continued)
Loosening
Note: Set the Forward/Reverse Valve (34) so that the anvil turns counterclockwise (reverse).
9. Place the socket (not included) over the nut you wish to loosen.
10. Grip the Impact Wrench firmly with two hands and gently squeeze the Trigger (21).
Note: If the Impact Wrench cannot loosen the nut, do not raise the air pressure on the
compressor over 120 PSI. Do not attempt to loosen the nut with the Impact Wrench.
Use other appropriate methods and tools to loosen the nut.
11. When the nut is loosened, release the Trigger (21). Turn off the air compressor and
disconnect the hose.
12. If needed, remove the nut from the socket.
Maintenance
1. Make sure your Impact Wrench is disconnected from the air hose before attempting
any maintenance.
2. Wipe the Impact Wrench down with a lint free cloth after each use.
3. Make sure the Anvil (43) is clear of dirt or debris. If possible, spray it with compressed
air before each use.
4. If you do not use an inline oiler/filter system, lubricate the tool daily by holding it so that
the Air Inlet (23) is facing up.Squeeze the Trigger (21), and place one or two drops of
oil into the Air Inlet (23). Squeezing the Trigger (21) allows the oil to circulate in the
motor.
5. Periodically, add a high quality machine oil to the oil inlet by removing the Oil Screw
(22). See FIGURE 6 below.
6. Repairs should only be done by a qualified service technician.
FIGURE 6
Oil Screw (22)
Remove the Oil Screw (22) with
the Wrench (54). Fill with a high
quality machine oil. Replace the
Oil Screw (22).
Note: A second oil plug, not
shown here, is located at the
front end of housing.

Page 8SKU 92427 For technical questions, please call 1-800-444-3353
Part No. Description Qty. Part No. Description Qty.
1 Bumper 1 28 Valve Spring 1
2 Spacer 1 29 0-ring 1
3 0-ring 1 30 Screw 1
4 Screw 4 31 Spring 1
5 Nut 4 32 Bearing 1
6 Motor Housing 1 33 Roll Pin 1
7 Bearing 2 34 Forward/Reverse Valve 1
8 Roll Pin 2 35 0-ring 1
9 Rear End Plate 1 36 Roll Pin 1
10 Cylinder 1 37 Reverse Valve 1
11 Rotor 1 38 Valve Bushing 1
12 Blade 6 39 Roll Pin 1
13 Roll Pin 1 40 Impact Ring 2
14 Front End Plate 1 41 Impact Cage 1
15 Handle Gasket 1 42 Impact Pin 2
16 Lock Washer 4 43 Anvil 1
17 Pistol Grip Handle 1 44 Front Shaft Bushing 1
18 Screw 4 45 Front Spacer 1
19 Roll Pin 1 46 0-ring 1
20 Roll Pin 1 47 Spring Ring 1
21 Trigger 1 48 Handle 1
22 Oil Screw 2 49 Screw 2
23 Air Inlet 1 50 Handrail 1
24 Air Filter 1 51 Screw 2
25 Throttle Valve Bushing 1 52 Clutch Housing 1
26 Valve Spring 1 53 B-ring 1
27 0-ring 1 54 Wrench 1
NOTE: Some parts are listed and shown for illustration purposes only and are not available
individually as replacement parts.
PLEASE READTHE FOLLOWING CAREFULLY
THEMANUFACTURER AND/ORDISTRIBUTOR HASPROVIDEDTHEPARTSDIAGRAMINTHIS
MANUALASAREFERENCETOOLONLY. NEITHERTHEMANUFACTURERNOR DISTRIBUTOR
MAKES ANY REPRESENTATION OR WARRANTY OF ANY KINDTOTHE BUYERTHAT 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 LICENSEDTECHNICIANS
ANDNOTBYTHEBUYER.THE BUYERASSUMES ALL RISKAND LIABILITYARISINGOUT 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.
Parts List

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Assembly Drawing
Note:The Wrench (54) is not shown.