Watson-Marlow 521CC - Manual (Page 22)

Rotor removal

Remove any tubing from the pumphead.

Open the flexible rotor cap in the centre of the rotor.

Undo and withdraw the central locating screw using a slotted screwdriver.

Pull the rotor hub off its dogged shaft.

Between the hub and the shaft is a split collet. If the collet
is retained by the shaft, pull it off, loosening it if necessary
by tapping it lightly. Avoid levering it off using a
screwdriver or other tool. If the collet is retained within
the hub, remove it, loosening it if necessary by reinserting
the central locating screw a turn or two and tapping the
screw head lightly.
Rotor replacement

Re-locate the split collet onto the drive shaft, rotating it until it fully engages the dog. Fit
the rotor body over the drive shaft as one unit.

Open the flexible rotor cap in the centre of the rotor. Use a slotted screwdriver to tighten
the central locating screw to a torque of 3Nm (2.2 lb-ft) to prevent collet slip during
operation. When fitted correctly, the tube guide rollers should align with the outer face of
the track. Close the flexible rotor cap.

Close the guard and ensure that the rotor is clear of the guard by observing the first few
rotor rotations.
Page 22 of 47 Watson-Marlow Bredel E-Manuals
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