General Pump KFZ Repair Manual

KKFFZZ

Repair Manual

GENERAL PUMP

INDEX

1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 3

2. REPAIR INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 3

2.1 Crank Mechanism Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 3

2.1.1 Crank mechanism disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 4

2.1.2 Crank mechanism assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 5

2.1.3 Disassembly/Assembly of bearings and shims . . . . . . . . . . . . . . .Page 6

2.2 Fluid End Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 9

2.2.1 Disassembly of the head - valve units . . . . . . . . . . . . . . . . . . . . . .Page 9

2.2.2 Head assembly - valve units . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 10

2.2.3 Disassembly of the head - seals . . . . . . . . . . . . . . . . . . . . . . . . . .Page 11

2.2.4 Plunger unit disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 12

2.2.5 Head assembly - seals - plunger unit . . . . . . . . . . . . . . . . . . . . . .Page 12

3. SCREW CALIBRATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 13

4. REPAIR TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 14

5. MAINTENANCE LOG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 15

A member of the Interpump Group

KFZ SERIES

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GENERAL PUMP

A member of the Interpump Group

KFZ SERIES

1. INTRODUCTION

This manual describes the instructions for repairing the KFZ Series Pumps, and must be carefully read and understood
before performing any repair intervention on the pump.

Correct use and adequate maintenance is fundamental for the pump’s regular operation and long duration. General
Pump declines any responsibility for damage caused by misuse or the non-observance of the instructions described in
this manual.

2. REPAIR INSTRUCTIONS

2.1 Crank Mechanism Repair

Crank mechanism repair operations must be carried out after draining the oil from the crankcase.
To drain the oil, remove the oil dipstick (1), and then the plug (2), in fig. 1.

Exhausted oil must be collected in an appropriate container and disposed of in appropriate
locations. In absolutely no case may it be disposed of in the environment.

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GENERAL PUMP

2.1.1 Crank mechanism disassembly

The correct sequence is the following:

A) Dissasemble:

• pump shaft key

• rear cover

• connecting rod cap

• side covers, using 3 wholly threaded M6 x 50 screws, inserting
them in the holes as shown in fig. 2.

A member of the Interpump Group

KFZ SERIES

B) Push the plunger guides and connecting rods forward in order to facilitate the lateral extraction of the
crankshaft. Two marks are visible on the crankshaft (3), as shown in fig. 3 and fig. 3a; they must be turned
towards the operator in order to facilitate extraction.

NOTE: to extract the plunger guide it is necessary to remove the ceramic plunger, and wiper first.

fig. 3a

fig. 3a

C) Disassemble the crankshaft oil seals and the plunger guides using standard tools.

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GENERAL PUMP

2.1.2 Crank mechanism assembly

After cleaning the crankcase, reassemble the crankcase mechanism as follows:

A) Thoroughly fit the plunger guide seals into their seat on the crankcase as shown in fig. 5a using the proper
tool (p/n F27904900).

B) Introduce the pre-assembled plunger guide/connecting rod units into their seat; to facilitate tightening of
the connecting rod cap, we advise to position the connecting rod so you can easily read the number. To
easily introduce the crankshaft, without the key, fully push in the plunger guide/connecting rod unit,
as indicated in section B, paragraph 2.1.1, and shown in fig. 4.

A member of the Interpump Group

KFZ SERIES

C) Before reassembly of the side covers, check the seal lips for wear. If replacement is necessary, position
the new ring using the correct tool (#F27904800) as shown in fig. 5.

If the shaft presents diameter wear corresponding to the sealing lip, to avoid the need for griding it’s
possible to position the ring as indicated in fig. 5.

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