General Pump SMH Operating instructions

SMH
Repair Manual
General Pump is a
member of the
Interpump Group Ref 300894 Rev. B
05-22

GENERAL PUMP A member of the Interpump Group SMH SERIES
Page 2
INDEX
1. INTRODUCTION ..................................................Page 3
2. REPAIR INSTRUCTIONS ...........................................Page 3
2.1 Repairing Mechanical Parts .......................................Page 3
2.1.1 Disassembly of Mechanical Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 4
2.1.2 Assembly of Mechanical Parts ..............................Page 15
2.1.3 Increase and Reduction Classes ............................Page 27
2.2 Repairing Hydraulic Parts ........................................Page 27
2.2.1 Dismantling the Head-Liners-Valves .........................Page 27
2.2.2 Assembling the Head-Liners-Valves .........................Page 31
2.2.3 Dismantling the Plunger Unit-Supports-Seals ..................Page 31
2.2.4 Assembling the Plunger Unit-Supports-Seals ..................Page 33
3. SCREW CALIBRATION ............................................Page 37
4. REPAIR TOOLS ..................................................Page 39
5. MAINTENANCE LOG ..............................................Page 40
Ref 300894 Rev. B
05-22

1. INTRODUCTION
This manual describes the instructions for Repairing SMH Series pumps, and must be carefully read and
understood before performing any repair intervention on the pump. Proper pump operation and longevity
depend on the correct use and maintenance. General Pump declines any responsibility for
damage caused by the misuse or the non-observance of the instructions described in this manual.
2. REPAIR INSTRUCTIONS
2.1 Repairing Mechanical Parts
Mechanical parts repair must be performed after removal of oil from the casing. To drain
the oil, remove the oil dipstick, (1, fig. 1) and then the draining plug (2, fig. 1).
Page 3
GENERAL PUMP A member of the Interpump Group SMH SERIES
The oil must be placed in a suitable container and disposed of in special centers.
It absolutely must not be discarded into the environment.
Read the contents of this manual carefully before each operation.
Danger Sign
Wear protective goggles.
Danger Sign
Put on protective gloves before each operation.
Ref 300894 Rev. B
05-22

Page 4
2.1.1 Disassembly of Mechanical Parts
The correct sequence is the following:
Completely empty the pump of oil, then disassemble the casing cover (and relative o-ring), unscrewing the (6)
M10 screws (1, fig. 2).
Remove the tab from the PTO shaft (1, fig. 3).
Unscrew the reduction gear cover fixing screws (1, fig. 4).
GENERAL PUMP A member of the Interpump Group SMH SERIES
Ref 300894 Rev. B
05-22

Page 5
Slowly screw in the 3 M8 screws (1. fig. 6) with the function of extractors to fully remove the cover unit and
pinion.
Complete disassembly of the reduction gear cover from the pinion is possible following these steps:
Remove the Seeger ring Ø 120 (1, fig. 7).
Position the 3 grub screws or M8 threaded screws (1, fig. 5) with the function of extractors in the holes and
two sufficiently long M10 screws with the function of supporting the cover (2, fig. 5).
GENERAL PUMP A member of the Interpump Group SMH SERIES
Ref 300894 Rev. B
05-22

Page 6
Separate the pinion from the cover, working with an extractor hammer on the pinion itself (1, fig. 8)
Remove the Seeger ring Ø 55 (1, fig. 9) and the bearing support ring (1, fig. 10) from the pinion.
Extract the seal ring from the reduction gear cover, working from the inner side of the cover (1, fig. 11).
GENERAL PUMP A member of the Interpump Group SMH SERIES
Ref 300894 Rev. B
05-22

Page 7
Remove the ring gear (1, fig. 14). Where necessary, it is possible to utilize an extractor hammer to be applied
on the (2) M8 holes (2, fig. 14).
Remove the tab from the shaft (1, fig. 15).
Unscrew the screws holding in the ring gear (1, fig. 12) and remove it (1, fig. 13).
GENERAL PUMP A member of the Interpump Group SMH SERIES
Ref 300894 Rev. B
05-22

Remove the ring gear support ring (1, fig. 16).
Remove the connecting rod caps with the lower semi-bearings, taking special care of the disassembly
sequence during disassembly.
The connecting rod caps and their relative half supports must be reassembled in exactly the
same order and coupling with which they were disassembled.
To avoid possible errors, caps and half supports have been numbered on one side (1, fig. 18).
Page 8
Unscrew the connecting rod screws (1, fig. 17).
GENERAL PUMP A member of the Interpump Group SMH SERIES
Ref 300894 Rev. B
05-22

Unscrew the reduction gear box fixing screws (1, fig. 22).
Page 9
Advance the half supports completely in the direction of the hydraulic part to allow the crankshaft to come
out. To facilitate this operation, use special too part #F27566200 (1, fig. 19).
Remove the three upper half bearings of the half supports (1, fig. 20).
GENERAL PUMP A member of the Interpump Group SMH SERIES
Ref 300894 Rev. B
05-22

Page 10
Slowly screw in the 3 M8 screws (1, fig. 24) to prevent the box from tilting too far and getting locked in the
housing. Remove the box while supporting the crankshaft to prevent damage (1, fig. 25).
Unscrew the bearing cover fixing screws from the opposite side (1, fig. 27).
Position the 3 grub screws or M8 threaded screws (1, fig. 23) with the function of extractors in the holes and
two sufficiently long M10 screws with the function of supporting the reduction gear box (2, fig. 23).
GENERAL PUMP A member of the Interpump Group SMH SERIES
Ref 300894 Rev. B
05-22