Procedures for Assembly and Disassembly of Hydraulic Pump Main Unit

1.Tools

The table below shows the tools required for assembly and disassembly of the K3V pump. The bolts and plugs may vary by pump type.

Tool name and dimensions Pump type (The ○ indicates a necessary part)

Name B K3V63 K5V80 Part name

K3V112 K5V140 K3V140/180 K5V200

Hexagon socket head bolt Rc mounted valve (Rc screw) PO plug (G screw)

Hexagon socket head locking screw

2 － － － M4

Hexagon wrench 2.5 － － － M5

3 － － － M6

4 ○ ○ ○ M5 BP-1/16 － M8 5 ○ ○ ○ M6 BP-1/8 － M10 6 ○ ○ ○ M8 BP-1/4 PO-1/4 M12 M14 8 ○ ○ ○ M10 BP-3/8 PO-3/8 M16 M18 10 M12 BP-1/2 PO-1/2 M20

12 M14 － － － 14 ○ 17 M16 M18 BP-3/4 PO-3/4 － ○ ○ M20 M22 BP-1 PO-1, 1 1/4, 11 /2 － 19 M24 M27 － － － 21 － － － －

Closed wrench Socket wrench Double-head (single-head) wrench 22 M30 － PO-2 － 19 ○ ○ ○ M12 M12 VP-1/4 － 22 ○ － － VP-3/8 － 24 ○ ○ M16 M16 － － 27 ○ ○ M18 M18 VP-1/2 － 30 ○ ○ M20 M20 － － 36 ○ ○ － － VP-3/4 － 41

50 ○ ○ － － VP-1 － － － VP-11/4 －

55

－ － VP-11/2 － Monkey wrench － ○ ○ ○ Medium-sized x 1 Screwdriver － ○ ○ ○ Medium-sized flathead screwdriver x 2 Hammer － ○ ○ ○ Plastic hammer x 1 Pliers － ○ ○ ○ For stop ring, TSR-160 Steel rod － ○ ○ ○ Key material steel rod, about 10X8X200 Torque wrench － ○ ○ ○ With adjustable specified torque tightening

2.Disassembly Procedure

When disassembling the pump, read the disassembly procedure thoroughly before following the sequence below. The numbers in parentheses after the part names are the codes indicated in

Attached diagram 1. Pump assembly cross-section diagram . [1] Select the location for disassembling the pump. •Find a clean location. •Place a rubber plate or cloth on the work platform so as not to damage the parts.

[2] Use cleaning oil to remove any dirt or rust from the surface of the pump.

[3] Remove the drain port plugs (468) and drain the oil from the pump casing. •Remove the plugs from both the front and rear pumps.

[4] Remove the hexagon socket head bolts (412) and (413) to remove the regulators, and then remove the hexagon socket head bolts (414) to remove the cover (326).

Loosen the 3 hexagon socket head bolts securing the electromagnetic proportional pressure reducing valve and casing subassembly (079), and remove the electromagnetic proportional pressure reducing valve and casing subassembly. •See the manual for the regulator for how to disassemble the regulators.

[5] Loosen the 4 hexagon socket head bolts securing the gear pump and remove the gear pump.

[6] Loosen the hexagon socket head bolts (401) fastening the swash plate support boards (251), pump casings (271), and valve block (312) together.

[7] Face down the pump regulator installation surface horizontally on the work platform, and separate the pump casings (271) and valve block (313). •When placing the regulator installation surface with the face down, be sure to place a rubber plate or similar material on the work platform so as not to damage the regulator installation surface. •When separating the pump casings and valve block, remove the 1st gear (116) at the same time.

[8] Remove the cylinder blocks (141) out from the pump casings (271) in a straight line in relation to the drive shafts (F) (111) and (R) (113), and remove the piston subassemblies (011), holder plates (153), spherical bushings (156), and cylinder springs (157) at the same time. •Be careful not to damage the sliding surfaces of the cylinder blocks, spherical bushings, shoes (152), and swash plates (212).

[9] Remove the hexagon socket head bolts (406), and remove the seal cover (F) (261). •The seal cover (F) can be easily removed by inserting a bolt into the hole (M6 tap) on the seal cover and then pulling the bolt out. •The seal cover (F) has an oil seal, so be careful not to damage the oil seal when removing the seal cover.

[10]Lightly strike the rear end sections of the drive shafts (F) (111) and (R) (113) to remove them from the swash plate support boards (251).

[11]Remove the shoe plates (211) and swash plates (212) from the pump casings (271).

[12]Lightly strike the installation flange sections of the swash plate support boards (251) on the pump casing (271) sides, and separate the swash plate support boards and the pump casings.

[13]Remove the valve plates (R) (313) and (L) (314) from the valve block (312). •These can also be removed in Step [7].

[14]If necessary, remove the stoppers (L) (534), stoppers (S) (535), servo pistons (532), and tilting pins (531) from the pump casings (271), and remove the needle bearing (124) from the valve block (312). •To avoid damaging the heads of the tilting pins, use a jig when removing them. •Loctite has been applied to the sections where the tilting pins and servo pistons are bonded, so be careful not to damage the servo pistons. •Try to avoid removing the needle bearings unless they are at the end of their service life. •Do not loosen the hexagon nuts of the valve block or swash plate support boards. This changes the flow volume setting.

3.Assembly Procedure

The assembly procedure is the reverse of the disassembly procedure. However, follow the precautions below. (1)Be sure to repair any parts damaged during disassembly, and prepare replacement parts in advance. (2)Thoroughly clean all parts with cleaning oil and air blow them before assembly. (3)Be sure to apply clean hydraulic oil to sliding parts and bearings before assembly. (4)As a rule, replace all O-rings, oil seals, and other seal parts with new parts. (5)Use a torque wrench to tighten all installation bolts and plugs to the torque specified in “Maintenance Standards.” (6)Be careful not to mix up the pump parts for the front and rear of the tandem pump. [1] Install the swash plate support boards (251) in the pump casings (271) by lightly striking them with a hammer. •When the servo pistons (532), tilting pins (531), stoppers (L) (534), and stoppers (S) (535) are removed, install these parts in the pump casings in advance. •To avoid damaging the heads of the tilting pins and the feedback pins (548), use a jig when tightening the servo pistons and tilting pins. Also be sure to apply Loctite (moderate strength) to the threaded sections.

[2] Attach the shoe plates (211) to the swash plates (212). Place the pump casings (271) with the regulator installation surfaces facing down, insert the tilting bushings (214) of the swash plates onto the tilting pins (531), and correctly mount the swash plates and shoe plates on the swash plate support boards (251). •Use the fingertips of both hands to check that the swash plates move smoothly. •Apply grease to sliding sections of swash plates and swash plate support boards for easier installation of the drive shafts (F) (111)and (R) (113). •Be careful not to damage the sliding surfaces of the shoe plates. [3] Install the drive shafts (F) (111) and (R) (113) with cylinder roller bearings (123), bearing spacers (127), and springs (824) set on them to the swash plate support boards (251).

[4] Attach the seal cover (F) (261) to the pump casings (271), and secure the cover with the hexagon socket head bolts (406).

Tightening torque: 29 N・m •Apply a thin layer of grease to the oil seal (774) inside the seal cover (F). •Be careful not to damage the oil seal when attaching it.

[5] Assemble the piston cylinder subassemblies (cylinder blocks (141), piston subassemblies (011), holder plates (153), spherical bushings (156), cylinder springs (157)), align piston subassemblies with the spherical bushings and cylinder splines and insert them into the pump casings.

[6] Install the valve plates (R) (313) and (L) (314) on the valve block (312) in alignment with the pins (885). •Be careful not to mistake the suction and discharge directions of the valve plates.

[7] Place the pump regulator horizontally on the work platform with the regulator installation surface facing down, and install the pump casings (271) and the valve block (312). •When placing the regulator installation surface with the face down, be sure to place a rubber plate or similar material on the work platform so as not to damage the regulator installation surface. •Install the valve block in the correct direction. (Install the valve block so that the regulator faces up and the suction flange faces right when looking at the valve block from the front.） •When installing the pump casings and valve block, install the 1st gear (116) at the same time. [8] Install the gear pump (04) with the 4 hexagon socket head bolts.

[9] Tighten the valve block (312) and pump casings (271) with the hexagon socket head bolts (401).

Tightening torque: 430 N•m •Assembly is easier when starting with the rear side pump.

[10]Tighten the hexagon socket head bolts (414) to the valve block (312) to attach the cover (326).

Tightening torque: 57 N•m

[11]Insert the feedback pins (548) of the tilting pins (532) into the feedback lever (611) of the regulators, install the regulators, and tighten the hexagon socket head bolts (412) and (413).

Tightening torque: 29 N•m •Install the regulator, making sure not to mistake the front and the rear of the regulator.

[12]Tighten the 3 hexagon socket head bolts to the valve block (312) to install the electromagnetic proportional pressure reducing valve and casing subassembly (079).

Tightening torque: 11.8 N•m

[13]Attach the drain port plugs (468) to finish assembly.

Tightening torque: 170 N•m