Aimco UOW Series Operating instructions

100000 SE Pine St., Portland, OR 97216 •800-852-1368 •503-254-6600 •www.aimco-global.com
UOW Series
Repair Manual
UOW-11 & UOW-T60 Series

2
Contents
Page
Number
1. Tools Needed for Repair 2
2. Disassembly and Reassembly of the Air Motor 3
•UOW-11 Air Motor 4
•UOW-T60 Air Motor 5
3. Disassembly and Reassembly of the Clutch
•UOW-T60 6
4. Disassembly and Reassembly of the Gear Section
•UOW-11 8
•UOW-T60 10
5. Disassembly and Reassembly of Bevel Gear Casing Assembly
•Pinion and Bevel Gear Section 12
•Socket and Gearing Section 13
•UOW Bevel Gear Casing 14
6. Toubleshooting and Preventative Maintenance
•UOW-T60 15
•UOW-11 15
Tools Needed for Repair
UOW Series Open-End Wrenches
1. Flat-Head Screwdriver
2. Dental Pick
3. Needle Nose Pliers
4. Pin Punch
5. Ball Peen Hammer
6. Pin Spanner Wrench (Hook Type)
7. Snap Ring Pliers
8. Crescent Wrench
9. Phillips Impact Driver
10. Spanner Wrench (Expanding Type)
11. Propane Torch
12. Thread Locker

3
Disassembly and Reassembly of the Air Motor
Disassembly
1. Remove the air motor casing from the gear casing connector.
2. Take hold of the end of the rotor and pull the air motor out of the casing.
3. Remove the front plate spacer and locking pin.
4. Pull the front plate off and remove the bearing.
5. Remove blades from the rotor.
6. Press the rotor out of the rear plate bearing and remove the bearing from the rear plate.
7. Thoroughly clean all parts.
Inspection
1. Bearings: Inspect bearings for knocking and side play.
2. Cylinder:Inspect cylinder for waviness.
3. Plates: Inspect plates for grooving.
4. Blades:Inspect blades for splitting and grooving on the sides and ends.
5. Silencer:Inspect silencer for dirt.
6. Replace all worn parts.
Assembly
1. Press greased bearing into the rear plate and over the rotor. Note:There should be a slight drag
between the rotor and the rear plate
2. Lightly oil the blade and install into the rotor flat-side out.
3. Slide the cylinder down over the rotor, and line up the roll pin with the center hole in the rear plate.
4. Grease bearing and press into the front plate. Install the front plate onto the rotor with bearing-side
up.
5. Slide the air motor assembly into the casing, lining up the pinion with the side of the front plate with
the slot in the casing.
6. Install locking pin and front plate spacer.
7. Thread the gear motor casing assembly onto the air motor casing and test the tool.

4
Disassembly and Reassembly of the Air Motor (cont.)
UOW-11 Air Motor
Part
Number
Description
Part
Number
Description
1
2
3
4
5
6
7
8
9
10
11
12
Front Plate Bearing
Front Plate
Blade
Rotor
Cylinder
Rear Plate
Rear Plate Bearing
Rear Plate Spacer
Packing
Motor Casing
Throttle Lever
Roll Pin
13
14
15
16
17
18
19
20
21
22
23
24
Air Inlet Bushing
Roll Pin
Valve Bushing
Reverse Valve
Valve Rod
O-Ring
Valve Plug
O-Ring
Cone Spring
Valve Rod Cap
Valve
Silencer

5
Disassembly and Reassembly of the Air Motor (cont.)
UOW-T60 Air Motor
Part
Number
Description
Part
Number
Description
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Front Plate Spacer
Pin
Blade
Roll Pin
Roll Pin
Rear Plate Bearing
Rear Plate Spacer
Casing Bushing
Packing
Casing
Throttle Lever
Roll Pin
Air Inlet Bushing
Front Plate Bearing
Front Plate
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
Rotor
Cylinder
Rear Plate
Valve Rod
Shut-off Valve
Valve Bushing
Reverse Valve
Valve Rod
O-Ring
Valve Plug
O-Ring
Cone Spring
Valve Rod Cap
Valve
Silencer

6
Disassembly and Reassembly of the Clutch
UOW-T60 Clutch
Disassembly
1. Separate the hammer casing from the hammer casing connector and remove the clutch assembly.
2. Remove the clutch spring, spring retainer, and backup ring from cam guide.
3. Carefully slide the cam ring up and remove the four balls from under it. Now remove the cam ring.
4. Lift the hooked end of the band spring out of the hole in the cam guide and slide it around the cam
guide until the end of the notch pin is exposed. Now remove the notch pin. CAUTION:Do not
bend or stretch the band spring.
5. Remove the retaining ring from the back of the cam guide.
6. Slide the cam and pilot pin out of the cam guide. Remove the pilot pin from the cam.
7. Remove the ball and spring out of the cam guide.
8. Clean all parts thoroughly.
Inspection
1. Cam:Inspect the cam lobes for grooving where they push the balls out against the cam ring.
2. Pilot Pin:Inspect the shoulder that is pushed up against the notch pin for rounding.
3. Notch Pin:Inspect the ends for rounding.
4. Cam Ring:Inspect the inside surface where the balls ride for pitting and grooving.
5. Balls:Inspect for pitting.
6. Spring:Inspect all springs for tension.
7. Replace all worn parts.
Assembly
1. Press the “G” pin into the pilot pin and install the pilot pin into the cam with the square-end up.
2. Put the spring and ball into the cam guide and slide the cam into the cam guide.
3. Install the retaining ring into the back of the cam guide.
4. Install the notch pin into the cam guide and slide the band spring back into place. Now rotate the
cam and make sure the notch pin is pushing the band up.
5. Put a small amount of grease into each of the holes in the cam guide and install the balls.
6. Slide the cam ring down onto the balls.
7. Put the backup ring and spring retainer down onto the cam ring.
8. Install the clutch spring and set the clutch assembly back in the tool.
9. Test the tool.

7
Disassembly and Reassembly of the Clutch (cont.)
UOW-T60 Clutch
Part
Number
Description
Part
Number
Description
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Hammer Casing Nut
Ball
Regulating Dial
Regulating Screw
Hammer Casing
Bearing
Spring Setter
Ball
Snap Ring
Torque Spring
Spring Retainer
Cam Ring
Spacer
Notch Pin
15
16
17
18
19
20
21
22
23
24
25
26
27
Notch Pin Band
Spring
Ball
Pilot Pin
Cam
Snap Ring
Thrust Bearing
Retainer
Outer Snap Ring
Cam Guide
Ball
G-Pin
Trust Washer

8
Disassembly and Reassembly of the Gear Section
UOW-11 Gear Section
Disassembly
1. Remove the gear casing from the air motor casing (right-hand threads).
2. Remove the first and second gear cage and planet gears.
3. Remove bearing from the gear case.
4. Clean all parts thoroughly.
Inspection
1. Gears:Inspect the teeth of the gear casing and the planet gears for pitting and grooving.
2. Needle Rollers: Inspect the needle rollers for wear.
3. Bearings: Inspect bearing for side play and knocking.
4. Replace all worn parts.
Assembly
1. Install the bearing into the gear case.
2. Install the second gear cage into casing.
3. Install the needle roller and second planet gears. Put a small amount of grease by each planet gear
and on the gear cage.
4. Install the gear cage spacer.
5. Install the needle roller and planet gear onto the first gear cage, then slide assembled gear cage into
gear casing (lightly grease all parts during assembly).
6. Install the gear casing assembly onto the air motor casing and test the tool.

9
Disassembly and Reassembly of the Gear Section (cont.)
UOW-11 Gear Section
Part
Number
Description
Part
Number
Description
1
2
3
4
5
6
Gear Casing
Bearing
Spacer
First Gear Cage
Planet Gear
Spacer
7
8
9
10
11
12
Bearing
Second Gear Cage
Planet Gear
Needle Roller
Needle Roller
Spacer

10
Disassembly and Reassembly of the Gear Section (cont.)
UOW-T60 Gear Section
Disassembly
Note:The UOW-T60 has gearings both before and after the clutch.
1. Remove the hammer casing connector from the air motor casing.
2. Remove the gear from the rotor.
3. Remove the gear cage and planet gear from the internal gear.
4. Remove the bearing from the internal gear.
5. Clean all parts thoroughly
Second Set of Gearing
1. Remove the gear casing from the hammer casing nut.
2. Remove the gear cage and planet gear from the internal gear.
3. Remove the bearing from the gear casing.
4. Clean all parts thoroughly.
Inspection
1. Gears:Inspect the teeth of the gear casing and planet gears for pitting and grooving.
2. Needle Rollers:Inspect the needle rollers for wear.
3. Bearings: Inspect the bearing for side play and knocking.
4. Replace all worn parts.
Assembly
Note:Assembly is the same on both gear assemblies.
1. Install the bearing into the gear cage.
2. Install the gear cage into the gear casing.
3. Install the needle roller and planet gears into the gear casing. Put a small amount of grease by each
planet gear and on the gear cage.
4. On the first gear assembly, install the rotor gear onto the rotor. On the second gear assembly, install
the second middle gear and gear cage spacer onto the cam guide.
5. Install the gear casing assembly onto the tool and test.

11
Disassembly and Reassembly of the Gear Section (cont.)
UOW-T60 Gear Section
Part
Number
Description
Part
Number
Description
1
2
3
4
5
6
Gear Casing
Bearing
Needle Roller
Planet Gear
Spacer
Second Internal Gear
7
8
9
10
11
Hammer Casing Nut
Hammer Casing Connector
First Internal Gear
First Gear Cage
Second Gear Cage

12
Disassembly and Reassembly of Bevel Gear Casing
Assembly
Pinion and Bevel Gear Section
Disassembly
1. Remove the bevel gear casing from the gear casing.
2. Remove the clamp ring (left-hand thread) and slide the pinion gear and bearing out of the housing.
3. Remove the four flush head screws from the bevel gear casing cover and remove the cover.
4. Remove the driven gear spindle assembly from the housing.
5. Press the bearing and bevel gear off of the driven gear spindle.
6. Clean parts thoroughly.
Inspection
1. Gears:Inspect gears for pitting and grooving.
2. Bearings: Inspect bearings for side play and knocking.
3. Replace all worn parts.
Assembly
1. Press the greased Bearing and spacer onto the driven gear spindle. Align the bevel gear up with the
key and press onto the driven gear spindle. Lightly grease all gears.
2. Install the pinion gear, shim, and greased bearing. Lightly grease all gears.
3. Install and tighten the Ball Bearing Support.

13
Disassembly and Reassembly of Bevel Gear Casing Assembly
(cont.)
Socket and Gearing Section
Disassembly
1. Remove the flush head screws holding down the cover plate.
2. Remove the cover plate.
3. Remove the gears, socket, and needle roller.
4. Remove the spring, checker, and notch pin.
5. Clean parts thoroughly.
Inspection
1. Gears: Inspect gears for pitting and grooving.
2. Needle Bearings:Inspect the needle bearings in gears for loose and/or missing needles.
3. Needle Rollers:Inspect the needle rollers for wear.
4. Inspect needle roller alignment holes in the bevel gear casing and gear casing cover for wear and out
of roundness.
5. Checker:Inspect the checker and checker spring for wear.
6. Replace all worn parts.
Assembly
1. Install the needle roller and notch pin into the bevel gear casing.
2. Install the checker and gearing.
3. Install the checker spring and rotate gearing in reverse by hand until it is stopped by the checker.
4. Align the socket opening with the casing.
Lightly grease all gears. Note: Do not over grease as this will cause the excess grease to come out as
the socket rotates through the casing opening.
5. Replace the gear casing cover and screws. Note:Torque the screws to 30 in. lbs. of torque and use a
good quality thread locker on the screws. These screws are one-time use only and should be replaced
with new screws.
6. Run and test the tool.

14
Disassembly and Reassembly of Bevel Gear Casing Assembly
(cont.)
UOW Bevel Gear Casing
Part
Number
Description
Part
Number
Description
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Bearing
Driven Gear
Key
Flush Head Screw
Spur Gear
Ratchet Gear
Needle Roller Bearing
Needle Roller
Socket
Spur Gear
Gear Casing Cover
Flush Head Screw
Needle Roller
Needle Roller
Needle Roller
Needle Roller Bearing
Needle Roller
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
Checker Spring
Checker
Middle Gear
Grease Cup
Spacer
Outer Snap Ring
Ball Bearing Support
Bearing
Driving Gear
Bevel Gear Casing
Needle Roller Bearing
Cam Spacer
Driven Gear Spindle
Adjusting Spacer
Bevel Gear Casing Cover
Flush Head Screw

15
Troubleshooting
UOW-T60
TROUBLE CAUSE SOLUTION
Tool operates intermittently
One or more of the shoulders
on the pilot pin is rounded
Replace pilot pin
Tool shuts off as soon as it is
started, or tool shuts off but
will not restart
Spring under pilot pin has lost
tension; notch pin is rounded.
Replace notch pin, band and/or
pilot pin. Replace spring
Band spring is stretched out of
shape.
The shoulders on pilot pin are
rounded
Loss of RPM
Exhaust filter is dirty causing
back pressure
Replace filter
Tool runs all the time
Value rod is stuck down
Disassemble clean and
reassemble
Air motor runs but socket does
not work
Broken gear in front head
Disassemble front head;
inspect and replace broken
parts
Low torque
Worn cam or worn air motor
Replace cam or rebuild air
motor
Socket does not stop in reverse
Broken checker spring
Replace checker spring
UOW-11
TROUBLE CAUSE SOLUTION
Loss of RPMs
Exhaust filter is dirty causing
back pressure
Replace filter
Tool runs all the time
Value rod is stock down
Disassemble, clean, and
reassemble
Air motor runs but socket does
not turn
Broken gear in front head
Disassemble front head;
inspect and replace broken
parts
Low torque
Worn air motor
Rebuild air motor
Socket does not stop in reverse
Broken checker spring
Replace checker spring
Recommended Preventative Maintenance:
Clean and inspect the tool every six months or 250,000 cycles.

16
CORPORATE HEADQUARTERS
10000 SE Pine Street
Portland, Oregon 97216
Phone: [phone]
Toll Free: 1-800-852-1368
WWW.AIMCO-GLOBAL.COM
AIMCO CORPORATION DE MEXICO SA DE CV
Ave. Cristobal Colon 14529
Chihuahua, Chihuahua. 31125
Mexico
Phone: [phone]
Fax: [phone]
LIT-MAN470 Rev. 03/11/19
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