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Repair
14
310796F
Displacement Pump
Disassembly
1.
Flush before repairing equipment, if possible. See
Hydra-Cat Operation manual 310795.
2.
Relieve pressure, page 8. Stop pump at bottom of
its stroke.
3.
Remove fluid outlet hoses (17, 18) and fittings (19,
20) from displacement pumps (110).
4.
Unscrew 90° swivel unions (131) from supply mani-
fold (130), then remove from outside displacement
pumps. On three pump models only, unscrew swivel
union (134) from center displacement pump.
5.
Remove locknuts (112) from displacement rods of
the two outer pumps. See F
. 2. Unscrew the two
outer locknuts (108) from the top of the tie plate
(109) on the two displacement pumps. Use a punch
and hammer to loosen.
6.
Remove the two outer pumps from tie plate.
Remove washers (107) from rods of each pump.
7.
On three pump models only, screw center pump's
displacement rod out of yoke (106), using a wrench
on flats of rod. Remove pump from yoke, then
remove washer (107) from pump rod.
8.
See manual 307944 for displacement pump repair.
Reassembly
1.
On three pump models only, slide center displace-
ment pump rod through tie plate (109), center lock-
nut (108), and washer (107). Thread displacement
rod into yoke (106) by turning complete cylinder.
Use a wrench on flats of displacement rod for final
tightening. Torque to 53-67 ft-lb (72-91 N•m). Push
cylinder up into place in tie plate and torque center
locknut (108) to 100-200 ft-lb (135-270 N•m).
2.
Slide the outer two displacement pump rods through
tie plate (109), outer locknuts (108), and washers
(107). Install locknuts (112) loosely on displacement
rods. Push cylinders up into place in tie plate and
torque outer locknuts (108) to 100-200 ft-lb
(135-270 N•m).
3.
Move air motor to bottom of its stroke. Check for
movement of air motor yoke at each displacement
rod. With rods centered, tighten locknuts (112)
securely and torque to 53-67 ft-lb (72-91 N•m).
4.
Tighten throat packing nut just enough to prevent
leakage, no tighter.
5.
Reconnect swivel unions to the pumps. Hold intake
valves steady with a wrench to prevent from turning.
WARNING
Read warnings, page 6.
Loosen tie rod nuts (119). Retorque tie rods (118)
into plate (104) to 75-85 ft-lb (101-114 N•m), then
retorque nuts (119) to 75-85 ft-lb (101-114 N•m).
Summary of Contents for Hydra-Cat TI5556b
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