Pratissoli KF5M Serie Manual De Reparación página 23

A) Unscrew the 12 M12x35 screws and the 4 M12 nuts
fastening the valve cover and the front cover, then remove
the covers (Fig. 16).
B) Remove the valve plugs by means of an M12 extractor
hammer (Fig. 16/a).
C) Extract the balls using a magnet or other tool (Fig. 16/b).
D) Move the suction and outlet valve housings using the tool
code 27922400 (see mechanical drawings in par. 4.1) as
indicated in Fig. 17, Fig. 17/a and Fig. 17/b.
Before working as per point D, make sure that the
piston is at Bottom Dead Centre.
Fig. 16/b
2.2.1.2
Fig. 17
To reassemble the various components, perform the
operations listed above in reverse order to par. 2.2.1.1.
In summary:
Assemble the suction and outlet valve seats using the
buffer  code 27702200 (see mechanical drawings in par. 4.1),
ensuring that the tapered surfaces of said seats are locked in
the tapered seats present on the head (Fig. 19 and Fig. 20).
Now position the ball in the seat (Fig. 20/a), reassemble the
valve caps and, at the front, reposition the valve covers. At the
front, calibrate the respective M12x35 screws and M12 nuts
with a torque wrench as indicated in chapter 3.
Fig. 17/a
23
Reassembly
Pay particular attention to the conditions of the
various components and replace if necessary.
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.
It is strongly advised to replace the O-Rings on the
valve caps at each inspection
Before repositioning the valve seats, thoroughly
clean and dry the relative housings in the head as
shown in Fig. 18.
Fig. 17/b
Fig. 18