Operating Manual
gearbox dismantled the pump will have to
be retimed as described in the timing
adjustment section.
To refit the rotors the recommended procedure
is as follows :-
- rotate the drive shaft until the keyway's
uppermost (not essential).
- find the master lobe of the rotor which
centre line is the same as that of the
spline teeth. See below.
- line the master lobe up with the shaft
spline and slide the rotor onto the shaft.
- find the master lobe of the remaining rotor
as previously done.
- slide the rotor on so that both rotors are in
the position shown below.
Correct timing has been achieved when
the pump rotates freely without contact
taking place between the rotors, this
should always be checked prior to running
the pump.
3. Replace the 'torque locking assemblies'.
Refer to section 8.1 on page 23 for full
details.
4. Before refitting the front cover examine
the 'O'ring and replace it if damaged. Fit
front cover and tighten the nuts up to the
recommended torque values.
9.7 Removal of Rear Gearcase Cover and
Replacement of Seal
1. Isolate the motor, remove any coupling or
Vee belt guards.
2. If the pump is direct coupled it will be
necessary to disconnect the coupling and
remove the pump from the baseplate before
removing the gearcase cover.
3. If the pump is belt driven, release the tension
on the belts and remove them, remove the
pulley and drive key.
4. Drain the oil from the pump.
5. Remove the retaining screws and then
remove the gearcase cover by sliding it
along the drive shaft. As the cover is
sealed to the gearcase with a liquid gasket
it may require a sharp tap with a mallet and
punch to break the joint.
6. With the cover removed, press out the oil
seal from the cover and replace with a new
seal.
7. Clean the faces of both the gearcase and
the end cover, coat the faces with a suitable
liquid gasket and refit the end cover.
Replace the retaining screws then
centralise the lipseal on the shaft before
tightening to the recommended torque
value.
8. Refill the pump with oil.
1. All rotors in the series D pump range have
sealing 'O' rings as described previously.
Check the condition of the 'O' rings and fit
new rings if necessary.
2. Rotors are fully interchangeable. When
refitting the rotors correct timing is achieved
by replacing the rotors in exactly the same
positions as when removed. If the gears
have been removed or the
9.8 Refitting the Rotorcases
centreline of lobe
spline tooth
centreline of
shaft
Master lobe
Master lobe
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