Danfoss PAH 2-6.3 User manual

danfoss.high-pressurepumps.com
Instruction
Disassembling and assembling
PAH 2-6.3, PAHT 2-6.3 and
PAHT G 2-6.3
MAKING MODERN LIVING POSSIBLE

Instruction Disassembling and assembling PAH 2-6.3, PAHT 2-6.3 and PAHT G 2-6.3
2180R9094 / 521B0985 / DKCFN.PI.011.N4.02 / 09.2013
Table of Contents 1. Disassembling ..........................................................................3
2. Inspection .............................................................................7
2.1 Port plate and valve plate ...............................................................7
2.2 Pistons..................................................................................7
2.3 Cylinder barrel ..........................................................................8
2.4 Housing ................................................................................8
2.5 Swash plate .............................................................................9
3. Assembling ............................................................................10
4. Spare parts list for PAH 2 / PAHT 2 ......................................................18
5. Exploded view PAH 2 / PAHT 2..........................................................19
6. Spare parts list for PAHT G 2 ............................................................20
7. Exploded view PAHT G 2 ...............................................................21
8. Spare parts list for PAH 4-6.3 / PAHT 3.2-6.3 .............................................22
9. Exploded view PAH 4-6.3 / PAHT 3.2-6.3 ................................................23
10. Spare parts list for PAHT G 3.2-6.3 ......................................................24
11. Exploded view PAHT G 3.2-6.3..........................................................25
12. Tool sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Note:
If the pump is dismantled during the warranty
period, the pump is no longer under warranty.
This document covers the instructions for
disassembling and assembling the axial piston
pumps PAH / PAHT / PAHT G 2-6.3.
Tools provided with tool set 180Z0235:
• Shaft bush, torpedo
• Press bush Ø18 (Plastic)

Instruction Disassembling and assembling PAH 2-6.3, PAHT 2-6.3 and PAHT G 2-6.3
3
180R9094 / 521B0985 / DKCFN.PI.011.N4.02 / 09.2013
3. Dismantle the front cover using a vice. 4. Remove the shaft seal using two screw-
drivers.
5. Remove the two small O-rings from the
ange. Remove the seal from the front
cover using a screwdriver.
6. Unscrew the four screws for the housing.
2. Remove the parallel key and unscrew the
front cover.
1. Tools required for dismantling.1. Disassembling

Instruction Disassembling and assembling PAH 2-6.3, PAHT 2-6.3 and PAHT G 2-6.3
4180R9094 / 521B0985 / DKCFN.PI.011.N4.02 / 09.2013 4
7. Remove the housing. 8. Remove the cylinder barrel.
9. Remove the pistons and the retaining plate
from the cylinder barrel.
NB: Items 10.1.a. and 10.1.b. concern
PAH 2, PAHT 2 and PAHT G 2 only
10.1.a. Remove the spring. 10.1.b. Remove the stop.

Instruction Disassembling and assembling PAH 2-6.3, PAHT 2-6.3 and PAHT G 2-6.3
5
180R9094 / 521B0985 / DKCFN.PI.011.N4.02 / 09.2013
NB: Items 10.2.a. through 10.2.c. concern
PAH 4-6.3, PAHT 3.2-6.3 and
PAHT G 3.2-6.3 only
10.2.a. Remove the retaining guide. 10.2.b. Remove the spring guide.
10.2.c. Remove the spring.
NB: The following items concern PAH 2-6.3,
PAHT 2-6.3 and PAHT G 2-6.3 only
11. Loosen the valve plate using two screw-
drivers. Place one of the screwdrivers in the
slot of the valve plate.
12. Remove the valve plate.

Instruction Disassembling and assembling PAH 2-6.3, PAHT 2-6.3 and PAHT G 2-6.3
6180R9094 / 521B0985 / DKCFN.PI.011.N4.02 / 09.2013 6
13. Remove the ve O-rings and the ve
back-up O-rings.
14. Remove the port plate from the ange.
15. Wash all parts and replace all seals
(inclusive shaft seal).
17. If the pump has failed, the reason for the
failure must be found and xed before the
repaired pump is re-installed.
16. Inspect all parts carefully (see “Inspection”)
and replace any worn parts.
Port plate
Stop
Spring
Valve plate
with sealing
Pistons
Retaining plate
Cylinder barrel
Front cover
Flange
Housing with
swash plate
and bearing

Instruction Disassembling and assembling PAH 2-6.3, PAHT 2-6.3 and PAHT G 2-6.3
7
180R9094 / 521B0985 / DKCFN.PI.011.N4.02 / 09.2013
2. Inspection 2.1 Port plate and valve plate
1. Neither port plate nor valve plate must
show any sign of wear.
2. Hold a ruler against the surface of the
plates and check the tightness against a
light source.
3. Check that both O-rings and back-up rings
are not broken and do not show severe
wear.
2.2 Pistons
1. The play in the ball and socket joint must
not exceed 0.1 mm.
2. The thickness of the piston shoes must be
at least 2.85 mm.
3. Hold a ruler against the surfaces of the
piston shoes to check that the surfaces are
even and smooth and without any scratches.
4. PAHT only:
It is acceptable that the (black) treated
surfaces of the pistons are partly worn o.

Instruction Disassembling and assembling PAH 2-6.3, PAHT 2-6.3 and PAHT G 2-6.3
8180R9094 / 521B0985 / DKCFN.PI.011.N4.02 / 09.2013 8
2.3 Cylinder barrel
1. Check the outer bearing surface for large
wear grooves (not critical).
3. Ensure that the pistons can move freely in
the bushings.
2. Check that the bushings are free from
seizure and large scratches.
2.4 Housing
1. Check that the swash plate surface is
smooth and without any big scratches
(depth more than 0.1 mm).
2. Check the bearing (the black part) for large
wear grooves (not critical).
1
2

Instruction Disassembling and assembling PAH 2-6.3, PAHT 2-6.3 and PAHT G 2-6.3
9
180R9094 / 521B0985 / DKCFN.PI.011.N4.02 / 09.2013
2.5 Swash plate
Mounted swash plate: 1. Unscrew center bolt from the swash plate.
2. Remove swash plate and guide pin. Guide pin

Instruction Disassembling and assembling PAH 2-6.3, PAHT 2-6.3 and PAHT G 2-6.3
10 180R9094 / 521B0985 / DKCFN.PI.011.N4.02 / 09.2013
3. Assembling
2. Parts and tools required for assembly.
Check that all parts are OK.
Replace all seals.
WARNING:
Do not use silicone when assembling the
pump. Do not reuse disassembled O-rings;
they might be damaged. Always use new
O-rings.
1. Lubrication:
• To prevent seizing-up, lubricate all threads
with PTFE lubrication type.
• O-rings inside pump may be lubricated
only with clean ltered water.
• O-rings for port ange, mounting ange
and ushing valve must be lubricated.
• It is important to lubricate ALL parts to be
assembled with clean ltered water
(Especially all PEEK parts).
Important:
It is essential that the pump is serviced in
conditions of absolute cleanliness. All parts
must be absolute clean before mounting.
3. Mount the O-ring on the ange. 4. Mount the port plate in its right position
using the pin as guide.
Guide
pin