Aimco Brakes Nutrunner URW Series Repair Manual

							PO 
Box  16460, Portland, OR   97292-0460  503-2 54-6600   Fax 503-2 55-2615  URW Series
  URW - 6, 8, 9, 10 & 12 Series  
Repair Manual  
www.aimco-global.com 
						

							 
 
 
Contents 
 
 
 Page 
 Number 
 
1. Tools Needed for Repair 1 
 
2. Disassembly and Reassembly of the Cam Casing 2-4 
 
3. Disassembly and Reassembly of the Gear Section 5-9 
 
4. Disassembly and Reassembly of the Air Motor Section 10-14 
 
5. Recommended Maintenance 15  
						

							- 1   -Tools Needed for Repair  
1. One  Set  of  T - H andle Metric Allen Wrenches
2. Flat - Bladed Screwdrivers
3. Brass Hammer
4. Dead Blow Hammer
5. 10 oz. Ball Pee n Hammer
6. One  Set  of  Pin Punches
7. One  Set  of  O - Ring Picks
8. 6”  Adj ustable End Wrench
9. 12”   Adjustable End Wrench
10. Medium Pair Channel Locks or Adjustable Jaw Pliers
11. Medium Honing Stone
12. 220 Grit Wet/Dry Sandp aper
13. Lap Plate
14. Loc - Tite #242
15. CFC Free Degreaser - Cleanser
16. Loc - Tite Accelerator
17. Arbor Press
18. UTA - 204 and UMS Tr ansducers and UFT Joint Simulators
19. Needle Nose Pliers
20. Propane Torch 
						

							- 2   -Disassembly and Reassembly of the Cam Casing  
Disassembly  
1. Remove the Rod Guide Bolts and Rod Guide Nuts.
2. Remove the Rod Guides, Ratchet, Checker, Springs ,   and Rod Plate Spring.
3. Rem ove the   Cam Casing from the tool (left - hand thread).
 On the URW - 6 ,   you must loosen the Gear Ca sing Lock Nut first and then  remove the Connector, Cam,
Bearing, Spacer, Thrust Washers ,   and T hrust  Bearing.
 On the URW - 8N  &   9N , over - tightening the Ha ndle Nut   will keep the Casing  from turning.
4. Remove the Operating Rod, Cam Roller, Cam Roller Pin, Cam   Roller Push Pin(s),  and Spring (s) .
5. Thoroughly clean all parts.
Inspection of Parts for Wear  
1. Rod Guides :    The Ratchet should turn freely in the Rod Guides   but  should not move from side to side;
r eplace as needed.
2. Ratchet and Checker :    T he teeth should come to a point; replace i f they are rounded off.   The flats inside
of the Ratchet s hould not be pitted or grooved;  replace as needed.
3. Operating Rod :    The end of   the Rod that contacts the Ratchet shou ld come to a point; replace  if  it’s
rounded .  
4. Cam Roller and Cam Roller Pin :    The Cam Roller sho uld be round and smooth; replace if  it has flat spots
and pitting.  The Cam Roller Pin should be inspect ed for shininess  and grooving;  replace as needed.
5. Rod Plate Spring :    Inspect the Rod Plate Spring for cracks an d wear from the Operating Rod;  replace as
needed.  
6. Springs :    Check for the c orrect dimension of the Spring;  replace as needed.
Reassembly  
1. Install the Cam Ro ller Push Pin (s)  and Spring (s)  into the Cam   Casing.   Put a light coat of grease on both
parts.
2. Install the Cam Roller and the Cam Roller Pin into  the Operating Rod.  Now install  the Operating Rod into
the Cam Casing making sur e that the Cam Roller Push   Pin  gets under the Cam Roller Pin.    Put a light coat
of grease on all parts.
3. Put a light coat of grease on the Operating Rod and install the Rod Plate Spring.
4. Install the Springs and  C hecker onto the Cam Casing.
5. Install the Ratchet and Rod Gui des being sure to lin e up the slot in the Rod Guide  with the notch on the
Checker.    Install the Rod Guide Bolts and Nuts and tighten.
6. When installing the Cam Casing Assembly back   onto the Gear Casing, the Cam  Casing Assembly will have
to be  shimmed   to  a djust the Operating Rod to the  Ratchet. 
						

							- 3   -Disassembly and Reassembly of the Cam Casing   (cont.)  
Adjusting the Cam Casing Assembly  
For all  T ools  E xcept the URW - 6 :  
1. While running the tool,  reinstall the Cam Ca sing to the Gear Casing.
2. Watch  the Ratc het as the Cam Casing turns down  onto the Gear Casing.  When the  Ratchet starts to turn ,
mark its position and conti nue to allow the Cam Casing to  turn down onto the Gear Casing until the R atchet
stops or the Cam Casing bottoms out.
3. T urn the Cam Casing   back half way between the two points and  measure the amount of Adjusting Spacers it
will tak e to take up the space between  the Cam Casing and the Gear Casing.
For the URW - 6   Only :  
1. Install the Connector into the Gear Casing.    Now inst all the Thrust Wash ers, Thrust  Bearing, Spacer,
Bearing ,   and Cam into the Connect or.
2. While running the tool,  reinstall the   Cam Casing onto the Connector.
3. Watch the Ratchet as the C am Casing turns down onto the Connector.  W hen the R atchet starts to turn,
mark its  po sition and continue to allow the Cam Casing to   turn onto the Connector until  the Ratchet stops
or the Cam Casing bottoms out .
4. Turn the Cam Casing back  halfway between the two points and measure the d istance from the bottom of the
Cam Casing   to the top  of the Gear Casing.
5. T ur n the Cam Casing down until it  bottoms  out  and measure the distance from the botto m of the Cam
Casing to the top  of the Gear Casing.    Subtract the two measu rements; this is the amount of  Adjusting
Spacers that should be put  betwe en the Cam Casing and the  Connector. 
						

							- 4   -Disassembly and Reassembly of the Cam Casing  (cont.)  
URW  -   Cam Casing  
Part 
Number   Description   Part 
Number   Description  
1  
2  
3  
4  
5  
6  
7  
8  
9  
10   Checker  
Ratchet  
Snap Ring  
Spring  
Rod Guide Left  
Round Head Scre w  
Rod Plate Spring  
Spring Washer  
Cam Roller Pin  
Operating Rod   11  
12  
13  
14  
15  
16  
17  
18  
19   Cam Roller  
Spacer (URW - 8N only)  
Rod Guide Nut  
Spring  
Cam Roller Push Pin  
Cam Casing  
Grease Cup  
Rod Guide Right  
Rod Guide Bolt   
						

							- 5   -Disassembly and Reassembly of the Ge ar Casing  
Disassembly  
1. Remove the Cam Casing (left - hand thread).
2. On the  URW - 6   Only :
a. Remove the Connector from the Cam Casing.    Remove the Cam, Bearing,  Spacer, Thrust Washers ,   and
Thrust Bearing.
b. Remove the Gear Casing, Gear Cage, Roller Pins, P lan et Gears, Needle Roller  Bearings ,   and Bearing.
c. Remove the Allen Head Dog Point Screw from the si de of the Gear Casing.  R emove the Internal Gear
and Bearing.
3. On the  URW - 8N & 9N :
a. Using   a  B earing  Separator,  put it between the Cam an d the Casing t o remove  the Cam, Key, Bearing,
Thrust Rear Spacer or Space r, and Thrust Bearing from  the Casing.
b. Remove the Casing from the Handle.
c. Remove the Air Motor from the Casing.
d. Remove the Bearing, Gear Cage, Needle Rollers, Pla net Gear Bushings ( on U RW - 8N only ),  and
Internal Gear from the Casing.
4. On the  URW - 8 :
a. Using   a  B earing  Separator,  put it between the C am and the Casing to remove  the Cam, Key, Bearing,
Thrust Rear Washer ,   and T hrust Bearing from the  Casing.
b. Remove the Gear Casing from the   Handle.
c. Remove the Gear Cage, Roller Pins, Planet Ge ar Bushings, and Planet Gears  from the Gear Casing.
d. Remove the Internal Gear from the Gear Casing.
5. On the  URW - 10N, 12N, 12NA & 12NB :
a. Remove the Cam, Bearing ,   and Spacer from the Gear Casing.
b. Remove the Gear Casing from the Casing.    Note :     Over - tightening the Handle Nut will help keep the
casing from turning.
c. Remove the Gear Cage, Planet Gear Pins, Needle  Roller Bearing, Bearing, and  Planet Gears from the
Gear Casing.
6. Thoroughly clean   all parts and blow dry.
Inspection of Parts  f or Wear  
1. Cam :    Ins pect for pitting and flat spots;   replace as needed.
2. Needle Rollers and Planet Gear Pins :    Insp ect for shininess and grooving;  replace as needed.
3. Planet Gears and Internal Gears :    I nspect   teeth for pitting and grooving;   replace as needed.
4. Bearings :    Inspect for side play and knocking; replace as needed. 
						

							- 6   -Disassembly and Reassembly of the Gear Casing   (cont.)  
Re assembly  
1. Grease all Bearings, Gears ,   and Internal Gears.
2. For   the  URW - 6   Only :
a. Install the Bearing, Internal Gear ,   and Allen He ad Dog Point Screw into the  Gear Casing.
b. Install the Needle Roller Bearing into the Planet   Gears and both Planet Gears  into the Gear Cage.    P ut
the Roller Pins in to the Gear Cage and thr ough  the Planet Gears.
c. Install the Spacer onto the Gear Cage and install  the Gear Cage into the Gear  Casing.    I nstall the
Bearing into the Gear Cage.
d. Install the Gear Casing onto the Air Motor Casing.
e. Install the Connector onto the Gear Casing and   insta ll the Thrust Washers,  Thrust Bearing, Spacer,
Bearing ,   and Cam into the Connector.
3. For the  URW - 8N & 9N :
a. Install the Internal Gear into the Casing.
b. Install the Planet Gear Bushing ( URW - 8N only ) in to the Planet Gear and install  them into the Gear
C age.    I nstall the Needle Rollers into the Gear Cage.
c. Install the Gear Cage into the Casing and install the Key into the Gear Cage.
d. Install the Bearin g, Thrust Rear Spacer or Spacer,  and Th rust Bearing onto the  Cam.    P ress the Cam
onto the Gear Cage makin g s ure to line up the Key  in the Gear Cage with the key  way   in the Cam.
Note :     The Gear Cage should  extend out past the Cam   about 2mm.
4. For the  URW - 8 :
a. Install the Internal Gear into the Gear Casing.
b. Install the Planet Gear Bushing into the Planet  G ears and install the Planet Gears into the Gear Cage.
I nstall the Needle Rollers into the Gear Cage.
c. Install the Gear Cage into the Gear Casing and in stall the Key into the Gear  Cage.
d. Install the Bearing, Thrust Rear Spacer or Spacer ,   and Thrust  Bearing onto the  Cam.    P ress the Cam
onto the Gear Cage mak ing sure to line up the Key  in the Gear Cage with the key way in the Cam.
Note :    The Gear Cage should  extend out past the Cam about 2mm.
5. For the  URW - 10N, 12N, 12NA, & 12NB :
a. Install the Needle   Roller Bearing into the Planet   Gears and both Planet Gears  into the Gear Cage.    P ut
the Planet Gea r Pins into the Gear Cage and  through the Planet Gears.
b. Install the Spacer onto the Gear Cage and install t he Gear Cage into the Gear  Casing.    I nstall the
B earing onto the Gear Cage.
c. Install the Bearing and Cam onto the Gear Cage. 
						

							- 7   -Disassembly and Reassembly of the Gear Casing  (cont.)  
URW - 6  -   Gear Casing  
Part 
Number   Description   Part 
Number   Description  
1  
2  
3  
4  
5  
6  
7  
8  
9  
10   Cam  
Bearing  
Thr ust Washer  
Connector  
Cam Casing Lock Nut  
Grease Cup  
Set Screw  
Spacer  
Roller Pin  
Needle Roller Pin   11  
12  
13  
14  
15  
16  
17  
18  
19  
20   Planet Gear  
Spacer  
Thrust Bearing  
Adjusting Spacer  
Gear Casing  
Bearing  
Internal Gear  
Gear Cage  
Bearing  
Spacer   
						

							- 8   -Disassembly an d Reassembly of the Gear Casing  (cont.)  
URW  -   Gear Casing  
Part 
Number   Description   Part 
Number   Description  
1  
2  
3  
4  
5  
6  
7   Cam  
Bearing  
Spacer  
Thrust Bearing  
Set Screw  
Gear Casing  
Internal Gear   8  
9  
10  
11  
12  
13   Key  
Planet Gear  
Roller Pin  
Bu shing  
Gear Cage  
Bearing