Service Training PV Series 42 PVplus Typical Service Tasks

Service of PVplus change shaft seal change shaft access to servo piston and servo sleeve add displacement feedback convert to horse power compensation change of contour sleeve pump disassembly replace internal components

Section through the PVplus, frame size 2, PV046

Change shaft seal, change shaft step 1: remove key Remove the key from keyed shaft, to avoid damage of the shaft seal

Change shaft seal, change shaft step 2: loosen the pilot cover When loosening the pilot cover, the barrel hold down spring is unloaded.

Change shaft seal, change shaft step 3: remove pilot cover Remove the pilot cover carefully

Change shaft seal step 4: exchange of shaft seal First assembly (new shaft) For first assembly (new shaft) press in shaft seal, assemble washer and snap ring. for repair (used shaft) assemble washer first and then press in shaft seal. Repair (used shaft)

Change shaft seal situation new / used pump New shaft: shaft seal first, then washer. shaft seal is located further out Used shaft: washer first, then shaft seal. sealing lip and dust protection lip are running on a new, un-damaged area further in the pump.

Change shaft step 4: remove shaft To remove the shaft set the pump on the end cover (shaft vertical). That avoids, internal parts moving and damaging sealing surfaces . (See next slide)

Change shaft step 4: remove shaft In this position all internal parts stay in their position. If the ingression of contamination is avoided, the pump can be used again without re-testing after assembling the replacement shaft.

Change shaft step 4: assemble new shaft Keyed shaft can be replaced by splined shaft or vice versa. by changing shaft and mounting flange,the pump can be converted from metric mounting interface to SAE interface.

Change shaft step 4: assemble new shaft Assemble shaft carefully by carefully turning insert the shaft into the barrel spline. Insert shaft carefully into the rear bearing. Front bearing must be below the mounting face before assembling the pilot cover.

Change shaft step 7: tighten bolts Mount pilot cover carefully. Avoid any damage of the shaft seal at the key slot or at the spline edges. First tighten two bolts only alternating. That compresses the barrel hold down spring.

Assemble of front bearing to the shaft

Access to servo piston and servo sleeve step 1: remove displacement adjustment Open servo piston cover with two-hole wrench.

Self made two hole wrench Proposal for a selfmade two holewrench. two bolts M4, M5 or M6 can be used as „pins“.

Access to servo piston and servo sleeve step 1: remove displacement adjustment The section view shows the location of the internal parts.

Access to servo piston and servo sleeve step 2: remove servopiston Washer and tapered sleeve can be removed by lifting the pump to vertical.

Section through PVplus, washer at servo piston at full stroke, swash angle = 18° Tolerance compensation: Not enough flow at full stroke: remove washer.

Section through PVplus, washer at servo piston at dead head, swash angle = 0° Tolerance compensation: Minimum flow at dead head: add washer.

Assembly PVplus displacement limiter Contains: servo piston plug stroke limiter seal-lock nut o ring

Assembly tapered-/contour sleeve and servo piston Assembly of servo piston, washer and feedback sleeve into the vertical standing pump makes it easier to „find“ the thread of the swash plate connnector. See also next slide.

Assembly tapered-/contour sleeve and servo piston (section view) Assembly of servo piston, washer and feedback sleeve into the vertical standing pump makes it easier to „find“ the thread of the swash plate connnector.

Access to servo piston and servo sleeve Displacement feedback is done via the tapered feedback sleeve. Tapered sleeve for pumps with electrical displacement feedback

Access to servo piston and servo sleeve Contour sleeve for pumps with mechanical displ. Feedback (hp control) Displacement feedback is done with the contoured sleeve.

Access to servo piston and servo sleeve disassembly with displacement feedback Putting the pump on one side avoids parts of the displacement feedback falling into the pump, when the servo piston and the feedback sleeve are removed. Alternatively the feedback device (LVDT or pilot cartridge) could be removed before removing the servo piston. Note: Do not change settings! Remark: With the pump vertical (shaft upwards) the feedback components also stay in place and the re-assembly of servo piston and feedback sleeve is easier.

Change of a PV with standard compensator to a horse power compensated version pilot cartridge contour sleeve plug M6 x 6

Disassembly of the pump step 1: Loosen bolts, remove three bolts If all 4 bolts are removed the internal parts of the pump can move uncontrolled and sealing surfaces could be damaged.

Disassembly of the pump, step 2: open, when pump is vertically Remove fourth bolt and lift housing. That keeps all internal parts in position. Shaft could still be in the housing or removed first. Servo piston should be removed before disassembly.

PVplus end cover Remove or assemble rotating group carefully, to avoid any damage of the metal to metal sealing surfaces. Air bleed valve Gasket (steel, coated and bossed)

PVplus swash plate The screw lock on the swash plate connector is good for 4 - 6 assemblies/disassemblies. The screw lock for the retainer screws is good for 2 assemblies/disassemblies. Nominal clearance of the slippers to the retainer is 0,03 - 0,09 mm. wear limit is: 0,15 mm.

PVplus cylinder barrel The spring is not dynamically loaded and needs not to be replaced for wear reasons. Caution when disassembling! Spring has high pre-load!

PVplus end cover, complete

PVplus servo piston sleeve

PVplus spring, carrier and washer

PVplus air bleed valve

PVplus end cover Bearing is pressed in. port plate to be mounted with brass side up. plug M6 x 6 to be removed for horse power compensated pumps.

PVplus, prepared for through drive

PVplus, with thru drive