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MAINTENANCE:
PARTS REPLACEMENT
1. If any of the O-rings have been removed or disturbed
during disassembly, they must be replaced with new O-
rings.
2. Excessive or continuous leakage from the tell-tale hole in
the bearing cover may be an indication of a damaged
mechanical seal. If a mechanical seal has been leaking,
it is recommended the entire seal be replaced. Refer to
"General Pump Troubleshooting" for possible causes of
seal leakage.
PUMP ASSEMBLY
Before reassembling the pump, inspect all component parts
for wear or damage, and replace as required. Wash out the
bearing/seal recess of the head and cylinder and remove
any burrs or nicks from the rotor and shaft.
1. Position the pump cylinder (12) with the bearing side
up.
2. Apply a small amount of quality O-ring lubricant in the
seal and bearing recess of the cylinder to facilitate
mechanical seal (153) installation.
3. Insert the seal jacket assembly (153A) into the seal
recess of the cylinder with the drive tangs of the jacket
inward.
4. With the polished face outward, align the notches of the
rotating seal face with the jacket, and install the seal
face (153F) and O-ring (153G) into the jacket assembly.
After installation, clean the seal face with a clean tissue
and alcohol.
5. Clean the polished face of the stationary seat (153B)
with a clean tissue and alcohol.
6. Install new O-ring (153D) onto stationary seat (153B).
7. Align the notch in stationary seat (153B) with the anti-
rotation pin in the cylinder (12) and insert it into the seal
recess with the polished face inward to mate with the
rotating face.
8. Hand pack the ball bearing (24) with grease. Refer to
"Lubrication" in the Pump Maintenance Section for the
recommended grease.
9. Install the bearing (24) into the cylinder recess. The
bearing balls should face outward, with the grease
shield inward. Ensure that the bearing (24) is fully and
squarely seated against the mechanical seal (153).
10. Keep the bearing (24) from falling out of the cylinder
(12) by securing with one of the bearing cover
capscrews (28) and a washer that will catch the outer
ring of the bearing when tightened.
11. Turn the pump cylinder (12) over with the INTAKE port
and relief valve to the
right
.
12. The models described in this IOM are Right Hand
Rotation only. A Right-Hand rotation pump will have the
drive end of the shaft (long end) protruding through the
cylinder (12) with the bearing cover on the head.
13. Apply a light coating of quality O-ring lubricant to the
shaft end to be inserted into the cylinder.
14. Insert the shaft into the cylinder (12). Carefully slide the
shaft through the installed mechanical seal (153) and
bearing. Align the notch in the rotor with the drive tang
on the seal jacket of the mechanical seal. Rotate the
shaft to ensure the drive tangs of the mechanical seal
are engaged in the notches in the rotor.
15. Install lockwasher (24B) on the shaft protruding through
the bearing in the cylinder with the tangs outward. Ensure
the inner tang “A” of the lockwasher is engaged in the slot
in shaft threads. Bend it slightly, if necessary. (See Figure
8.)
16. Install locknut (24A) onto threads of shaft with the tapered
end inward.
17. Tighten the locknut (24A) with a spanner wrench to pull the
rotor flat against the back wall of the cylinder. DO NOT
overtighten the locknut and bend or shear the inner tang.
Adjustment to the locknuts will be made after the head is
installed.
18. Insert the vanes (14) into the slots in the rotor, ensuring
that the relief groove is facing toward the direction of
rotation. See Figure 6
19. Apply a light coating of quality O-ring lubricant in the seal
and bearing recess of the head (20) to facilitate
mechanical seal (153) installation.
20. Insert the seal jacket assembly (153A) into the seal recess
of the head with the drive tangs of the jacket inward.
21. With the polished face outward, align the notches of the
rotating seal face with the jacket, and install the seal face
(153F) and O-ring (53G) into the jacket assembly.
22. Clean the polished face of the stationary seat (153B) with
a clean tissue and alcohol.
23. Install new O-ring (153D) onto stationary seat (153B).
24. Align the notch in stationary seat (153B) with the anti-
rotation pin in the head (20). Insert it into the seal recess
with the polished face inward to mate with the rotating
face.
25. Hand pack the ball bearing (24) with grease. Refer to
"Lubrication" in the Pump Maintenance Section for the
recommended grease.
26. Install the bearing (24) into the head recess. The bearing
balls should face outward, with the grease shield inward.
Ensure that the bearing (24) is fully and squarely seated
against the mechanical seal (153).
27. Apply a small amount of quality O-ring lubricant to the O-
ring groove on the inside face of the head and install a
new head O-ring (72) in the groove by laying the O-ring flat
and starting in on one side of the groove, stretching ahead
with the fingers, as shown in Figure 7.
Figure 7 Head O-ring Installation
