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4.4 Assembly
4. Maintenance
Step 2
Locate one rotor (17) on to the drive shaft (24) with the dimple
at the top. Turn the rotor through 45°. Fit the second rotor on
to the auxillary shaft (25) with its dimple at the top as shown.
Step 3
Turn the shaft so that the rotors are in the new positions as
shown.
Step 4
Using feeler gauges measure between the points indicated,
turning the shaft as required.
Step 5
If the measurement points are unequal tap the rotor which is on the free turning shaft until equal measurement through 8 points is
achieved.
Step 6
Tighten the torque locking assemblies or clamp plate screws. Confirm timing is still correct. Remove the rotors.
Dimples
4.4.6 Adjusting rotor timing
Step 1
If the rotor timing requires adjustment (and assuming the pump has not yet been re-built), it is important to establish the cause for
the rotors mistiming before proceeding.
To allow timing adjustment ensure that one shaft is able to rotate within the torque locking assembly/element. The other torque
locking assembly/element should be tightened to the recommended torque.