Insert the suction and outlet valve units,
checking that they are fully inserted in the head
seat.
Then apply the valve covers and calibrate the
respective M12x35 screws torque wrench at the
required tightening torque
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 casing, and at the intervals indicated in the
"PREVENTIVE MAINTENANCE" table in chapter 11 of the Use
and maintenance manual.
-
Remove the 4 plugs closing the suction valve cover holes
(Fig. 41).
-
Unscrew the two external screws fixing the M12x160
head replacing them with two M12 threaded bars (Fig. 42,
pos. ) to avoid damaging the pistons, then remove the
remaining screws.
Fig. 40/a
-
-
Fig. 41
27
Separate the head from the pump casing.
Extract the high pressure seals from the head and the
low pressure ones from the support, being careful not to
damage the respective housings (Fig. 43).
Pay attention to the order of seal pack
disassembly as indicated in Fig. 44 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. 42
Fig. 43
Fig. 44