Dismantling The Head - Seals; Dismantling The Piston Unit - Interpump Group Pratissoli HS Serie Manual De Reparación

Insert the suction and outlet valve units with
their bushes, checking that they are fully
inserted in the head seat. Take special care not to
damage the anti-extrusion rings on the bushes
(Fig. 28, pos. ƒ). For correct positioning and
adjustment of rings in their respective seats:
• Insert the bushes completely in the head,
lubricating the external O-ring/anti-extrusion
rings diameter with OCILIS type silicone
grease code 12001600.
• Remove the bushes, verifying the integrity of
all the anti-extrusion and O-rings.
• Proceed with final reassembly.
• Then apply the valve covers and calibrate the
respective M14x40 screws. For the values of
the torques and tightening sequences follow
the instructions in chapter 3.
2.2.3 Dismantling the head – seals
Replacement of the seals is necessary from the moment you
begin to detect water leaks from the drainage holes provided
on the back of the pump casing, and at the intervals indicated
in the "PREVENTIVE MAINTENANCE" table in chapter 11 of the
Use and maintenance manual.
A) Unscrew the M12x150 head fixing screws as indicated in
Fig. 29.
B) Separate the head from the pump casing.
C) Extract the high pressure seals from the head and the low
pressure ones from the support, using simple tools as
indicated in Fig. 30, pos. , being careful not to damage
the respective housings.
Pay attention to the order of seal pack
disassembly as indicated in Fig. 31 for HS20
version pumps and in Fig. 31/a for HS18 version
pumps, composed of:
1. Head ring
2. HP seal
3. Restop ring
4. Seal support
5. LP seal
6. Seal ring
7. Circlip
8. O-ring
Fig. 28
Fig. 29
2.2.4

Dismantling the piston unit

The piston unit does not require any routine maintenance.
Maintenance is limited to visual checks only.
To extract piston units: Unscrew the M7x1 piston fixing screws
as indicated in Fig. 32.
23
Fig. 30
Fig. 31
Fig. 31/a