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5 Maintenance
5.4.9 Fitting primary seals
Step 1
Refer to section 5.5 for seal fitting instructions.
5.4.10 Fitting rotors
Step 1
1. Fit new rotor O rings (18).
2. Fit rotors (17) onto the shafts (24 and 25) with both dimpled
rotor master lobes in the 6 -12 o’clock position (horizontally
ported pumps) or 3-9 o’clock position (vertically ported
pumps). For the rotor on the drive shaft the rotor dimple should
be aligned with the drive shaft keyway.
For series 6 pumps the rotors are retained by torque locking
assemblies, TLA´s. Slide the TLA assembly onto the shaft. Locate
the clamp plate tool and tighten to the recommended torque
figure. Tighten the TLA screws to the recommended torque figure.
Unscrew the clamp plate tool and remove. Replace the rotor cap
and tighten to the recommended torque figure.
For Bi-lobe rotors:
Fit rotors (17) onto the shafts (24 and 25) at an angle of 45° as
shown. Rotate pump one full revolution ensuring there is no rotor
contact.
Step 2
Fit new O rings (20) to rotor retention nuts (22).
Use a wooden/plastic block between the rotors to stop
them turning whilst tightening the rotor retention nuts to the
recommended torque settings shown in Technical Data (chapter
6 Technical data).
Step 3
To check rotors are correctly synchronised turn the drive shaft (24) by hand and check meshing clearances with feeler gauges
against recommended clearance figures as shown in 6.2 Pumphead Clearance information.
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