General Pump HF Repair Manual - Manual (Page 14)

GENERAL PUMP
A member of the Interpump Group
HF SERIES
Page 14
Check them for wear; replace if necessary.
At each disassembly, all the O-rings of the plunger unit must be replaced.
2.2.5 Head Assembly - Seals - Plunger unit
Reassemble the various components by inverting the operations previously listed in paragraph 2.2.3, paying
careful attention to the following:
A) Sealing packing: follow the same order used during disassembly.
B) Lubricate components 2,3 and 5 with silicone grease type OCILIS, p/n F12001600; this operation is also
considered necessary in order to facilitate the settling of the seal lip on the plunger.
C) For correctly assembling the HP seals in their related seats on the head without damaging the lips, use the
appropriate tools depending on the pumping assembly diameters as indicated in Chapter 4.
D) Reassemble the plungers by fastening the screws with a torque wrench, following the fastening torque
value indicated in Chapter 3.
E) Reassemble the head proceeding as follows:
1. Position the seal supports in their respective seats on the crankcase;
2. Using two screws - auxiliary pin (p/n F27508200) fastened to the crankcase as indicated in fig. 29,
position the complete head, being sure that it is centered on the central plunger only.
3. Complete the operations by following the fastening procedures; for fastening torque values and
sequences, follow what is indicated in Cha[ter 3.
Ref 300623 Rev.A
01-12
2.2.4 Plunger Unit Disassembly
The plunger unit does not require periodic maintenance. Service interventions are limited to visual inspections
only. for plunger unit extraction operate as follows:
Unfasten the M7x1 plunger screws as shown in fig. 28.