Danfoss APP Series, APP 5.1, APP 10.2, APPW 5.1, APPW 10.2 Service Manual

Service guide

APP pumps

APP(W) 5.1-10.2
Disassembling and assembling

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Service guide | Disassembling and Assembling, APP(W) 5.1-10.2

© Danfoss | DCS (im) | 2017.062 | 180R9238 | DKCFN.PI.078.F3.02 | 521B1196

Table of Contents

NOTE: If the pump is disassembled within the warranty period, the pump is no longer covered
by the warranty.

Introduction

This document covers the instructions for
disassembling and assembling the axial piston
pump APP(W) 5.1-10.2

Tools needed:

• Toolset (code no. 180B4162)

• Seal set (code no. 180B4161)

• Screwdriver

Important: It is essential that the pump is
serviced in conditions of absolute cleanliness.

To understand the pump design better, please
see exploded view on last page.

WARNING: Do not reuse disassembled O-ring
or shaft seal as they might be damaged.

Contents

Introduction ................................................................................................................................................................................2

1. Disassembling the pump ..............................................................................................................................................3

2. Assembling the pump ...................................................................................................................................................5

3. Disassembling swash plate ..........................................................................................................................................6

4. Assembling swash plate ................................................................................................................................................7

5. Change of shaft seal .......................................................................................................................................................8

6. Exploded view for APP (W) 5.1-10.2 ......................................................................................................................12

Service guide | Disassembling and Assembling, APP(W) 5.1-10.2

© Danfoss | DCS (im) | 2017.06 180R9238 | DKCFN.PI.078.F3.02 | 521B1196 | 3

1. Disassembling the pump

2. Unscrew the 8 screws in the mounting
flange.

5. Carefully remove the shaft seal assembly
using the shaft-seal extractor supplied,
provided with the tool set. The extractor
must fit underneath the shaft seal.

7. Remove the pistons, retainer plate, stop
bush and retainer ball from the cylinder
barrel.

1. Unscrew the seal-retaining ring
counterclockwise and remove it.

4. Wet the shaft and shaft seal with clean
(filtered) water.

3. Carefully remove the mounting flange
from the housing.

6. Remove the whole cylinder barrel and
carefully place it on a suitable clean
surface.

Service guide | Disassembling and Assembling, APP(W) 5.1-10.2

© Danfoss | DCS (im) | 2017.06 180R9238 | DKCFN.PI.078.F3.02 | 521B1196 | 4

8. Carefully remove the valve plate assembly
using a screwdriver.

11. Mount the new O-rings.

13. Remove the port plate by hand.

10. Mount the new back-up rings on the new
valve plate.

9. Remove the O-rings and back-up rings
from the valve plate.

12. Carefully press, by hand, the cylinder
barrel onto the valve plate.

Mount backup
ring first

Then mount
O-ring