Operation Manual
To aid re-assembly, note which components
came off which shaft. Good engineering practise
suggests that components removed from a
shaft should be assembled on the same shaft.
If removing the front cover for any reason
check that rotorcase retaining nuts are tight
before replacing.
8.2 Removing the front cover
1. Remove the 'R' clips (2) and carefully
loosen the front cover retaining nuts (3)
as there may still be residual pressure in
the system.
2. Remove the front cover nuts and take off
the cover (6). If stuck, loosen by tapping
with soft mallet at overlap at sides.
Do not lever off.
3.
Flush out the pump head before
continuing.
4. Remove the 'O' ring (7) from the front
cover.
8.3 Removing the rotors
1.
Insert a plastic block between the two
rotors (13) to stop them turning.
2. Using a spanner remove the rotor nuts
(9). These nuts have right hand threads.
3. The rotors can be removed from the shafts
(28,29) by hand or by using the extractor
tool supplied with the pump to aid
disassembly. Unscrew the central bolt
until flush on the inside, screw the tool two
full turns into the rotor. Whilst preventing
the tool from turning screw in the central
bolt. The rotor is jacked off the shaft for
hand removal.
Central bolt
8.4 Product seal removal
1.
'O' ring- Refer to section 10
2.
Mechanical Seal - Refer to section 11
8.5 Removing the rotorcase
1.
Remove the rotorcase retaining nuts. (5).
2. Gently tap the rotorcase (11) on each side
with a soft mallet to release it from the
bearing housing. (18)
3.
The rotorcase will be supported on
the studs (4) during removal.
4. The rotorcase and seal housing (66) can
be removed as an assembly.
STP125 Page 18
