Page 6 of 8 666250-XXX-C (en)
MATERIAL CODE
[A] = Aluminum [GPS] = Glass lled Polyphenylene Sul de
[B] = Nitrile [Ny] = Nylon
[Bz] = Bronze [SS] = Stainless Steel
[C] = Carbon Steel [U] = Polyurethane
[D] = Acetal [Z] = Zinc

AIR MOTOR SECTION SERVICE

Service is divided into two parts - 1. Pilot Valve, 2. Major Valve.
GENERAL REASSEMBLY NOTES:
Air Motor Section service is continued from Fluid Section repair.
Inspect and replace old parts with new parts as necessary. Look
for deep scratches on metallic surfaces, and nicks or cuts in “O”
rings.
Take precautions to prevent cutting “O” rings upon installation.
Lubricate “O” rings with Key-Lube.
Do not over-tighten fasteners. Refer to torque speci cation
block on view.
Re-torque fasteners following restart.

PILOT VALVE DISASSEMBLY

Remove (104) retaining ring.
Remove (123) screws and (122) “O” rings.
Remove (118) piston rod, (121) sleeve bushing, (119) “O” rings
and (120) spacers from the (101) motor body.
Remove (103) sleeve and (102) “O” rings.
y
y
y
y
y
y
1.
2.
3.
4.

PILOT VALVE REASSEMBLY

Replace two (102) “O” rings, if worn or damaged, and reinstall
(103) sleeve.
Install one of the (121) sleeve bushings, (119) “O” rings, (120)
spacers and the remaining (121) bushing.
Carefully push (118) pilot rod into bushings etc. and retain on
each end with the two (122) “O” rings. Retain with (123) screws.
Replace (104) retaining rings.

MAJOR VALVE DISASSEMBLY

Remove (107) plate and (108 and 117) gaskets.
On the side opposite the air inlet, push on the inner diameter
of (111) spool. This will force the (109) piston out. Continue
pushing the (111) spool and remove. Check for scratches and
gouges.
Reach into the air section (exhaust side) and remove (116)
spacer, (115) spacers, (113) “O” rings, (114) “O” rings, (112) wash-
ers. etc. Check for damaged “O” rings.

MAJOR VALVE REASSEMBLY

Replace (112) washer, (114) “O” ring and (113) “O” ring onto (115)
spacer and insert etc. NOTE: Be careful to orient spacer legs
away from blocking internal ports.
Lubricate and carefully insert (111) spool.
Install (117) gasket and (107) plate.
Lubricate and install (110) packing cup and insert (109) piston
into (air inlet side) cavity. The (110) packing cup lips should
point outward.
Install (108) gasket and replace (107).
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2.
3.
4.
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2.
3.
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2.
3.
4.
5.
PARTS LIST / 6662XX-XXX-C AIR MOTOR SECTIONAIR MOTOR PARTS
Item Description (size) Qty Part No. Mtl
101 Motor Body (1) 96374 [A]
p
102 “O” Ring (1/16” x 1-1/4” o.d.) (2) Y325-24 [B]
o
103 Sleeve (1) 94528 [D]
p
104 Retaining Ring (1-5/32” i.d.) (2) Y145-26 [C]
105 Screw / Lockwasher (1/4” - 20 x 5/8”)
(models 6662X0-XXX-C, 6662X1-XXX-C
and 6662X2-XXX-C)
(8) 93860 [C]
Cap Screw (1/4” - 20 x 5/8”) (models
6662XA-XXX-C, 6662XB-XXX-C and
6662XC-XXX-C)
(8) Y6-42-T [SS]
106 Lockwasher (1/4”) (models 6662XA-
XXX-C, 6662XB-XXX-C and 6662XC-XXX-C)
(8) Y14-416-T [SS]
107 Plate (2) 96424 [SS]
p
108 Gasket (with notch) (1) 96426 [B/Ny]
o
109 Piston (1) 96422 [D]
p
110 “U” Cup (3/16” x 2-1/8” o.d.) (1) Y186-55 [B]
o
111 Spool (1) 96421 [A]
o
112 Washer (2.055” o.d.) (5) 93251 [GPS]
p
113 “O” Ring (1/8” x 1-3/4” o.d.) (5) Y325-222 [B]
p
114 “O” Ring (3/32” x 2-1/16” o.d.) (6) Y325-134 [B]
o
115 Spacer (4) 93250 [GPS]
Item Description (size) Qty Part No. Mtl
o
116 Spacer (1) 96420 [D]
p
117 Gasket (1) 96425 [B/Ny]
118 Pilot Rod (1) 93309-2 [C]
p
119 “O” Ring (1/8” x 3/4” o.d.) (4) 93075 [U]
120 Spacer (3) 115959 [Z]
121 Sleeve Bushing (2) 98723-2 [Bz]
p
122 “O” Ring (3/32” x 9/16” o.d.) (2) 94820 [U]
p
123 Screw (#8 - 32 x 3/8”) (4) Y154-41 [C]
126 Pipe Plug (3/4 - 14 PTF x 17/32”) (1) Y227-6-L [C]
127 Pipe Fitting (1-1/4 - 11-1/2 NPT x 1-1/2 -
11-1/2 NPT)
(1) 96451 [C]
128 Pipe Plug (1/8 - 27 PTF x 1/4”) (1) Y227-2-L [C]
197 Button Head Screw (1/4” - 20 x 1/4”) (2) 94987 [SS]
198 Button Head Screw (1/4” - 20 x 3/8”) (1) 94987-1 [SS]
201 Mu er Kit (includes item 127) (1) 67389
n p
Key-Lube “O” Ring Lubricant (1) 93706-1
10 Pak of Key-Lube (10) 637175
p
Indicates parts included in 637434 air section service kit.
o
“Smart Parts“, keep these items on hand in addition to the service kits for fast repair and reduction of down time.