SPX FLOW 006-U3, Instruction Manual, Page: 88 / 136

Maintenance Waukesha Cherry-Burrell
®
Brand Universal 3 Pump
Page 88 95-03103 02/2021
6. Tighten the gear locknuts to the specified torque, using a
gear nut driver tool.
7. Bend the locking tab on the lock washers into the locking nut
slots, securing the gear locknut into place (Figure 217).
Checking for Proper Clearance
Waukesha Cherry-Burrell brand pumps are designed with close
running clearances. Backface clearances are set with shims
during assembly.
Shafts are positioned with shims behind the front bearing and
locked into gear case with the bearing retainers. Rotors lock
against the shaft shoulder. Clearance between the body backface
and the back of the rotor wing is called backface clearance.
1. To check backface clearance, first mount the body (less
seals) onto the housing. Assemble the rotors and secure
them with rotor jam nuts.
2. With feeler gauges, measure the rotor backface clearance
(Figure 218, item A), through the port or from the front.
3. Measure the rotor front face clearance (Figure 218, item C).
4. Measure the rotor to body clearance (Figure 218, item B).
5. Check the measured clearances against Table 18, “Rotor
Clearances,” on page 89.
6. Make corrections as required and follow examples in
Table 19, “Backface Clearance Corrections,” on page 89, to
determine the exact adjustment to make and to avoid
unnecessary assembly/disassembly.
7. To make shim adjustments, first remove the rotors, body and
shafts. Make the required shim adjustment and reassemble.
(Figure 218, item D is the front bearing rear shim.)
8. Re-check the backface clearances. Be sure both rotors have
the same clearance to avoid crossover interference with the
adjacent rotor hub.
Figure 216 - Install Gear Locknuts
PD100-059a
Table 17: Torque Values and Gear Nut Driver Tool
Model U3 Pumps Gear Nut Torque Tool Part Number
006, 014, 015, 018
120 ft-lb(163 N·m)
030, 034, 040
045, 060, 064, 130, 134 140 ft-lb (190 N·m)
180, 184, 220, 224 230 ft-lb (312 N·m)
210, 214, 320, 324 320 ft-lb (434 N·m)
Figure 217 - Bend Locking Tab
PD100-057a
39
39
NOTE: It is generally best to keep
backface clearance to a minimum.
CAUTION
Backface clearance for both rotors must
be equal to avoid crossover interference
with the adjacent rotor hub.
Figure 218 - Clearance Measurements
A C
B
D
PD100-650