Pratissoli KF5M Serie Manual De Reparación página 26

2.2.3.2 Reassembly
A) Fit the bush on the spacer (Fig. 26) and tighten the unit on
the piston guide rod (Fig. 26/a).
In the event that replacement is being carried out
with the wiper already assembled, lubricate the
bush and take care, during insertion, not to damage
the wiper seal lip.
For the tightening torques, follow the instructions in chapter 3.
2.2.4 Piston seal
2.2.4.1 Disassembly
Piston seal replacement is necessary whenever heavy
bentonite leaks are detected from the opening under the
head spacer. However, an indication of estimated component
replacement intervals is present in the table in Fig. 18 in
chapter 11 of the Use and maintenance manual. It is plausible
to think that the state of wear of the components will be
strongly correlated with the type of fluid and the percentage
of the presence of solid residues.
To extract the piston seal, bring the entire unit to Top Dead
Center and operate as follows:
A) Remove the front cover as indicated in Fig. 21.
B) Remove the front plugs by means of an M12 extractor
hammer.
C) Unscrew the M8 screws on the piston unit and remove
them together with the seal fastening bush (Fig. 27).
D) Using an M12 cover screw, tighten using a T-handle
wrench on the seal support so that it acts as an extractor
(Fig. 27/a). After this, once the seat has come out, extract
the pack, composed of the support and the piston seal
(Fig. 28).
Fig. 26
Fig. 26/a
The O-ring present on the seal support should be
replaced at each disassembly.
26
Fig. 27
Fig. 27/a
Fig. 28