Central Pneumatic 91107 User manual

3/8” STUBBY AIR RATCHET WRENCH
3491 Mission Oaks Blvd., Camarillo, CA 93011
Visit our Web site at http://www.harborfreight.com
For technical questions and replacement parts, please call 1-800-444-3353
Model 91107
®
Copyright©2004byHarborFreightTools®. Allrights reserved. Noportion
of this manual or any artwork contained herein may be reproduced in any shape
or form without the express written consent of Harbor FreightTools.
OPERATING INSTRUCTIONS
®

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SKU 91107
Specifications
Save This Manual
You will need the manual for the safety warnings and precautions, operating and mainte-
nance 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 lit. 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.
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.
Maximum Torque 40 Ft. Lbs.
Average Air Consumption 2.8 CFM
Drive Size 3/8” Square
Air Inlet 1/4” - NPT Female
Maximum Air Pressure 90 PSI
Maximum Rotation Speed 280 RPM @ 90 PSI
Ratchets Per Minute 160

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SKU 91107
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 changing accessories or 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 trigger 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 the trigger 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 air compressor
without heating up. Otherwise, the extension cord could melt and catch fire, or cause
electrical damage to the air compressor. 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.
21. Do not use a “cheater” or other extension to increase torque on this tool. Do not
exceed the maximum torque rating on this tool.

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SKU 91107
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.
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.)
Unpacking
When unpacking, check to make sure the parts listed on page 6 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.
Operation
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. Youwill need to preparea1/4”NPT air connector (soldseparately)toconnect to the airinlet
on the Ratchet. First, wrap the 1/4” air connector (not included) with pipe thread seal tape
before threading it into the Air Inlet (1). Connect the 3/8” ID Air Source Hose to the Ratchet.
Note: If you are not using an automatic oiler system, before operation, add a few drops of
Pneumatic Tool Oil to the airline connection. Add a few drops more after each hour of con-
tinual use.
2. Set the air pressure on your compressor to 90 PSI. Do not exceed the maximum air
pressure of 90 PSI.
3. Check the air connection for leaks. Disconnect the Ratchet from the air source.
Ratchet
1/4” - NPT

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SKU 91107
Operation (continued)
Maintenance
Throttle Lever (48)
Air Inlet (1)
Reverse Switch (35) Air Regulator (6) (see inset below)
Warning! Always disconnect the Ratchet from the air source hose before attempting any
maintenance.
1. Wipe the unit down with a lint free cloth.
2. Periodically apply a high grade, light machine oil to the Trigger Pivot area (see above).
3. Make sure the Ratchet Anvil (38), the Air Inlet (1), and the Reverse Switch (35) are clear of
grease, dirt, or debris.
4. Store the Ratchet in a clean, dry location, out of reach of children.
Trigger Pivot Area
Ratchet Anvil (38)
Warning! Disconnect the Ratchetfrom the airsource
whenattachingand removing sockets(not included). There
isnosafety lockmechanismon this tool;alwaysdisconnect
from the air source when not in use.
Refer to the photograph above.
1. Attach a 3/8” drive socket (not included) to the Ratchet
Anvil (38).
2. By following the directions on page 4, attach the Ratchet to the air source hose.
3. While holding the Ratchet securely with both hands, gently press the Throttle Lever
(48) to activate the Ratchet. Do not force the unit;allow it to do the work for you. Do not
overtighten hardware with this item. To change direction (loosen vs. tighten), stop the
tool and move it away from the workpiece, then turn the Reverse Switch (35).
4. Toadjustthetorque,readjustthe air pressurebychangingthesettingonthecompressor,
or, you can fine tune the air pressure by gently turning the Air Regulator (6) with a
standard screwdriver. Turn the knob toward “L” (Counterclockwise) for low and “H”
(Clockwise) for high. Turn the knob gently or you will break the plastic Air Regulator (6)
knob. Do not exceed the maximum air pressure of 90 PSI. See the Air Regulator Inset
above.
5. When you are finished working, turn off the compressor and disconnect the air source
hose.
Warning! There may still be air in the Ratchet. Squeeze theThrottle Lever (48) and activate
the Ratchet to expel any air still inside the tool.
6. Remove the socket (not included).
Air Regulator Inset
L
H

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SKU 91107
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 HAS PROVIDEDTHE PARTSDIAGRAMINTHIS
MANUAL AS A REFERENCE TOOL ONLY. NEITHER THE MANUFACTURER NOR DISTRIBU-
TORMAKESANY REPRESENTATION ORWARRANTYOFANYKINDTOTHE 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/ORDISTRIBUTOREXPRESSLYSTATESTHATALLREPAIRSANDPARTSREPLACEMENTS
SHOULD BE UNDERTAKEN BY CERTIFIED AND LICENSEDTECHNICIANS AND NOT BYTHE
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 PARTSTHERETO.
Parts List
Part No. Description Part No. Description
1 Air Inlet 27 Needle Bearing
2 Air Inlet O-ring 28 Planet Cage Bushing
3 Muffler Deflector 29 Internal Gear Spacer
4 Muffler Deflector O-ring 30 Ratchet Housing
5 Motor Housing 31 Crankshaft
6 Air Regulator 32 Drive Bushing
7 Dowel Pin 33 RatchetYoke
8 Air Regulator O-ring 34 Dust Cover
9 Throttle Valve Spring 35 Reverse Switch
10 Throttle Valve Stem 36 Anvil Upper Washer
11 Throttle Valve O-ring 37 Spring Pin
12 Throttle Valve O-ring 38 Ratchet Anvil
13 Regulating Valve 39 Spring
14 Regulating Valve O-rings 40 Bearing
15 Bearing 41 Ratchet Spring
16 Rear Plate 42 Lock Pin
17 Cylinder 43 Ratchet Pawl
18 Rotor 44 Ratchet Pawl Pin
19 Rotor Blade 45 Thrust Washer
20 Front Plate 46 Motor Clamp Washer
21 Bearing 47 Retaining Ring
22 Internal Gear 48 Throttle Lever
23 Idler Gear Plate 49 Throttle Lever Pin
24 Idler Gear Pin 50 Housing Cover
25 Idler Gear 51 Muffler Deflector Ring
26 Clamp Nut

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SKU 91107
Assembly Drawing
18
20
35
48
24
39
49
21 11
41
45
46