General Pump SM Repair Manual

SM

8

Repair Manual

General Pump is a
member of the
Interpump Group

Ref 300894 Rev.A

06-12

GENERAL PUMP

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. REPLACING THE CONECTING ROD FOOT BUSHINGS . . . . . . . . . . . . . . . . . .Page 40

6. MAINTENANCE LOG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 41

A member of the Interpump Group

SM SERIES

Ref 300894 Rev.A

06-12

Page 2

GENERAL PUMP

A member of the Interpump Group

SM SERIES

1. INTRODUCTION

This manual describes the instructions for Repairing SM 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).

The oil must be placed in a suitable container and disposed of in special centers.
It absolutely must not be discarded into the environment.

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GENERAL PUMP

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).

A member of the Interpump Group

SM SERIES

Remove the tab from the PTO shaft (1, fig. 3).

Unscrew the reduction gear cover fixing screws (1, fig. 4).

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GENERAL PUMP

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).

Slowly screw in the 3 M8 screws (1. fig. 6) with the function of extractors to fully remove the cover unit and
pinion.

A member of the Interpump Group

SM SERIES

Complete disassembly of the reduction gear cover from the pinion is possible following these steps:
Remove the Seeger ring Ø 120 (1, fig. 7).

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GENERAL PUMP

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.

A member of the Interpump Group

SM SERIES

Extract the seal ring from the reduction gear cover, working from the inner side of the cover (1, fig. 11).

Ref 300894 Rev.A

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GENERAL PUMP

Unscrew the screws holding in the ring gear (1, fig. 12) and remove it (1, fig. 13).

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).

A member of the Interpump Group

SM SERIES

Remove the tab from the shaft (1, fig. 15).

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GENERAL PUMP

Remove the ring gear support ring (1, fig. 16).

Unscrew the connecting rod screws (1, fig. 17).

A member of the Interpump Group

SM SERIES

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).

Ref 300894 Rev.A

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GENERAL PUMP

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).

A member of the Interpump Group

SM SERIES

Unscrew the reduction gear box fixing screws (1, fig. 22).

Ref 300894 Rev.A

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GENERAL PUMP

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).

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).

A member of the Interpump Group

SM SERIES

Unscrew the bearing cover fixing screws from the opposite side (1, fig. 27).

Ref 300894 Rev.A

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GENERAL PUMP

Position the 3 grub screws or M8 threaded screws (1, fig. 28) with the function of extractors in the holes.

Slowly screw in the 3 M8 screws (1, fig. 29) to prevent the cover from tilting too far and getting locked in the
housing. Remove the bearing cover while supporting the shaft to prevent damage. (1. fig. 30).

A member of the Interpump Group

SM SERIES

Remove the crankshaft casing from the PTO side (1, fig. 31).

Ref 300894 Rev.A

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GENERAL PUMP

In the event that it is necessary to replace one or more connecting rods or plunger guides, operate as follows:
unscrew the screws with tool part #F27566200 to unlock the connecting rods (1, fig. 32) and then extract the
connecting rod/plunger guide units from the back casing opening (1, fig. 33).

A member of the Interpump Group

SM SERIES

It is now possible to disassemble the plunger guide seal rings, taking care to not damage the plunger guide
sliding rod.

Whenever it becomes necessary to replace the plunger guide seal rings without
dismantling the entire mechanical part, it is possible to extract the seal rings with the
use of tool part #F27918500 operating as follows:

Insert the tool between the rod and the seal ring (1, fig. 34) and, with the extractor hammer, complete
insertion of the tapered section inside the seal ring (1, fig. 35).

Ref 300894 Rev.A

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GENERAL PUMP

Extract the seal ring using the tool extractor hammer (1, fig. 36).

Remove the two spindle locking Seeger rings Ø 120 (1, fig. 37).

A member of the Interpump Group

SM SERIES

Remove the spindle (1, fig. 38) and extract the connecting rod (1, fig. 39).

Ref 300894 Rev.A

06-12

Page 13