INGERSOLL RAND COMPANY LTD
209 NORTH MAIN STREET – BRYAN, OHIO 43506
(800) 495-0276 y FAX (800) 892-6276 © 2010 C
CCN 99768657
www.ingersollrandproducts.com
OPERATOR’S MANUAL 66266-XXX-B
INCLUDING: SERVICE KITS, TROUBLESHOOTING, PARTS LIST,
DISASSEMBLY & REASSEMBLY.
RELEASED: 1-8-99
REVISED: 10-18-10
(REV. 04)

CHOP-CHECK STYLE

LOWER PUMP ENDS

Also covers 637074-X43-B service kits

READ THIS MANUAL CAREFULLY BEFORE INSTALLING,

OPERATING OR SERVICING THIS EQUIPMENT.

It is the responsibility of the employer to place this information in the hands of the operator. Keep for future reference.

SERVICE KITS

Use only genuine ARO® replacement parts to assure com-
patible pressure rating and longest service life.
637074-X43-B for general repair of 66266-XXX-B lower
pump ends.

GENERAL DESCRIPTION

WARNING
DO NOT EXCEED MAXIMUM OPERATING
PRESSURE AS INDICATED ON PUMP MODEL PLATE.
WARNING
REFER TO GENERAL INFORMATION SHEET
FOR ADDITIONAL SAFETY PRECAUTIONS AND IMPOR-
TANT INFORMATION.
This manual only covers the lower pump section. It is one
of four documents which support an ARO pump. Replace-
ment copies of these forms are available upon request.
650XXX-X Pump Model Operator’s Manual.
General Information for Air Operated or Hydraulically
Operated Pumps.
: Lower Pump End Operator’s Manual.
Air or Hydraulic Motor Operator’s Manual.
The chop-check design provides for easy priming of the
lower foot valve. The double acting feature is standard
in all ARO industrial pumps. Material is delivered to the
pump discharge outlet on both the up and down stroke.

MAINTENANCE

The air / hydraulic motor is completely separate from the
lower pump end. This helps to keep the motor from being
contaminated by the material being pumped. Periodically,
ush entire pump system with a solvent that is compatible
with the material being pumped.
Keep solvent cup  lled with this compatible solvent. This will
keep material from drying on the piston rod, which would
drag thru the packings, ruin them and eventually scour the
piston rod.
Provide a clean work surface to protect sensitive internal
moving parts from contamination from dirt and foreign mat-
ter during disassembly and reassembly.
Before reassembling, lubricate parts as required. When as-
sembling “O” rings, or parts adjacent to “O” rings, exercise
care to prevent damage to “O” rings and “O” ring groove sur-
face.
y
y
y
yTROUBLE SHOOTING
No material at outlet (pump continually cycles).
Check material supply. Disconnect or shut o the air sup-
ply and replenish the material, reconnect.
Material on one stroke only (fast downstroke).
The (21) check may not be seating in the (22) seat (see
lower pump disassembly). Remove the check from the
seat, clean and inspect the check and seat area. If the
check or seat is damaged, replace.
Material on one stroke only (fast upstroke).
The (34) valve rod may not be seating in the (28) seat (see
lower pump disassembly). Remove the valve rod from the
seat, clean and inspect the valve rod and seat area. If the
valve rod or seat is damaged, replace. Check for worn or
damaged packings. Replace the packings as necessary.
Material leakage out of the solvent cup or material ap-
pears on the pump plunger rod.
Relieve the pressure in the pump and tighten the solvent
cup until leakage discontinues. If this procedure does not
aid in stopping the leakage problem, the upper packings
may be worn (see lower pump disassembly). Replace the
packings as necessary.
y
y
y
y

LOWER PUMP END DESCRIPTION CHART

66266 - X 4 3 - B
Service Kit Selection
Example: Lower Pump End # 66266-C43-B
Service Kit # 637074-C43-B
66266 - X 4 3 - B
Packing Plunger
637074 - X 4 3 - B
Packing Material
3 - Glass lled PTFE (upper and lower)
C - UHMW-PE (upper and lower)
G - UHMW-PE / Leather staggered (upper and lower)
P - UHMW-PE / Glass  lled PTFE staggered (upper)
- UHMW-PE (lower)
R - Glass lled PTFE / UHMW-PE staggered (upper)
- Glass lled PTFE (lower)
Plunger Type
3 - Hardened stainless steel with hard chrome plating
Spring Arrangement
4 - Multiple wave spring