Hyundai Excavator R210LC-7. Service and repair manual - page 29

8 - 37

DISASSEMBLY

The figure in (  ) shown after the part name
in explanation sentence shows its number
in the construction figures.

Place control valve on working bench

Disassemble the valve in a clean and dry
environment and pay careful attention not
to damage the sealing flange faces.

3)

(1)

Travel straight valve block

Loosen hexagon socket head bolts to and
remove straight travel valve block(103) in
its assembled state.

Hexagon wrench : 14mm

(2)

Main spool

Loosen hexagon socket head bolts(273)
and remove spring cover(201, 203).

Hexagon wrench : 6mm

(3)

Remove spool, springs, stopper, spring
seats and spacer bolt in spool assembly
condition from casing.
When extracting each spool assembly
from its casing, pay attention not to
damage the casing.

21078MC09

21078MC10

21078MC11

8 - 38

Covers

Loosen hexagon socket head bolts(273)
and then remove the spool cover(202,
204).

Hexagon wrench : 6mm

(4)

Removal of port relief

Remove port relief valves(602) from
casing.

Socket wrench : 32mm

(5)

Removal of plug

(Option section)

Remove plugs(553) from casing.

Socket wrench : 27mm

(6)

Lock valve

Loosen hexagon socket head bolts and
remove lock valve(252).

Hexagon wrench : 5mm

(7)

21078MC12

21078MC13

21078MC14

8 - 39

Negative control relief valve

Remove plug(551).

Hexagon wrench : 12mm

(8)

Swing logic valve and check valve

Loosen hexagon socket head bolts(251)
and remove logic valve(251) and take
check valve(254).
Remove plug(551) or (552) and take out
poppet(511) or (515, 516) and spring
(521) or (523).

Hexagon wrench : 6, 12mm

(9)

Boom priority valve

Loosen hexagon socket head bolts(104)
and remove boom priority valve(104).

Hexagon wrench : 10mm

(10)

Remove poppet(611), spring(621) and
damping rod(631).

21078MC15

21078MC16

21078MC17

8 - 40

Inspection after disassembly

Clean all disassembled parts with clean mineral oil fully, and dry them with compressed air.
Then, place them on clean papers or cloths for inspection.

Control valve

Check whole surfaces of all parts for burrs, scratches, notches and other defects.
Confirm that seal groove faces of casing and block are smooth and free of dust, dent, rust etc.
Correct dents and damages and check seat faces within the casing, if any, by lapping.
Pay careful attention not to leave any lapping agent within the casing.
Confirm that all sliding and fitting parts can be moved manually and that all grooves and path's
are free foreign matter.
If any spring is broken or deformed, replace it with new one.
When a relief valve does not function properly, repair it, following it's the prescribed disassembly
and assembly procedures.
Replace all seals and O-rings with new ones.

Relief valve

Confirm that all seat faces at ends of all poppets and seats are free of defects and show uniform
and consistent contact faces.
Confirm manually that main poppet and seat can slide lightly and smoothly.
Confirm that outside face of main poppet and inside face of seat are free from scratches and so
on.
Confirm that springs are free from breakage, deformation, and wear.
Confirm that orifices of main poppet and seat section are not clogged with foreign matter.
Replace all O-rings with new ones.
When any light damage is found in above inspections, correct it by lapping.
When any abnormal part is found, replace it with a completely new relief valve assembly.

(11)

a.
b.
c.

d.

e.
f.

g.

a.

b.
c.

d.
e.
f.
g.
h.

8 - 41

ASSEMBLY

General comments

In this assembly section, explanation only is shown.
For further understanding, please refer to the figures and photographs shown in the previous
structure & disassembly section.
Figure in (  ) shown after the part name in the explanation refers to the reference identity number
shown on the structure section.

Cautions in assembling seals

Pay close attention to keeping all seals free from handling damage and inspect carefully for
damage before using them.
Apply clean grease or hydraulic oil to the seal so as to ensure it is fully lubricated before
assembly.
Do not stretch seals so much as to deform them permanently.
In fitting O-rings, pay close attention not to roll them into their final position in addition, a twisted
O-ring cannot easily untwist itself naturally and could thereby cause inadequate sealing and
thereby both internal and external oil leakage.
Tighten fitting bolts for all sections with a torque wrench adjusted to the respective tightening
torque.

Check valve

Assemble poppet(511, 515, 516) and spring(521, 523).
Put O-rings(561) on to plug(551, 552).
Tighten plug(551, 552) to the specified torque.

Hexagon wrench : 12mm
Tightening torque : 23~27kgf m(166~195lbf ft)

Negative control relief valve

Assemble the poppets, springs and damping rods(2 611) together into casing A(101).
Put O-ring(561) on to plug(551) and tighten the latter to its specified torque.

Hexagon wrench : 12mm
Tightening torque  : 23~27kgf m(166~195lbf ft)

Lock valve

Put O-rings onto the casing.
Tighten hexagon socket head bolts to their specified torques.

Hexagon wrench : 5mm
Tightening torque : 1~1.4kgf m(7.23~10.12lbf ft)

Main relief, port relief valves

Install main relief valve(601), port relief valve(602) into the casing and tighten to the specified torque.

4)

(1)

(2)

(3)

(4)

(5)

a.

b.

c.
d.

e.

Main relief valve

Port relief valve

Spanner 32mm

Socket wrench 32mm

7~8

7~8

50.6~57.8

50.6~57.8

Component

Tools

Tightening torque

kgf m

lbf ft

8 - 42

Main spools

Carefully insert the previously assembled spool assemblies into their respective bores within of
casing A(101) and casing B(102).
Fit spool assemblies into casing A(101) and casing B(102) carefully and slowly.   Do not under
any circumstances push them forcibly in.

Covers

Fit spool covers(202, 204) to the non-spring assembly end of the spool, and tighten the
hexagonal socket head bolts(273) to the specified torque.

Hexagon wrench : 6mm
Tightening torque : 2.5~3.5kgf m(18~25.3lbf ft)

Confirm that O-rings(169, 264) have been fitted.
Fit spring covers(201, 203) to the spring end for the spools, and tighten hexagon socket head
bolts(273) to the specified torque.

Hexagon wrench : 6mm
Tightening torque : 2.5~3.5kgf m(18~25.3lbf ft)

Confirm that O-rings(261, 262) have been fitted.

Travel straight valve, swing logic valve and boom priority valve

Put O-rings onto the casing.
Tighten hexagon socket head bolts to their specified torques.

(6)

(7)

(8)

Travel straight valve

Swing logic valve

Boom priority valve

Hexagon wrench 14mm

Hexagon wrench   6mm

Hexagon wrench 10mm

28.0~32.0

2.5~3.5

8.5~11.5

202~231

18.0~25.3

61.5~83.1

Component

Tools

Tightening torque

kgf m

lbf ft

8-43

1. REMOVAL AND INSTALL OF MOTOR

REMOVAL 

Lower the work equipment to the ground
and stop the engine.

Operate the control levers and pedals
several times to release the remaining
pressure in the hydraulic piping.

Loosen the breather slowly to release the
pressure inside the hydraulic tank.
Escaping  fluid  under  pressure  can
penetrate  the  skin  causing  serious
injury.
When pipes and hoses are disconnected,
the oil inside the piping will flow out, so
catch it in oil pan.

Disconnect hose assembly(2).

Disconnect pilot line hoses(3, 4, 5, 6, 7).

Sling the swing motor assembly(1) and
remove the swing motor mounting bolts
(8).

Â

Motor device weight : 230kg(507lb)

Remove the swing motor assembly.
When removing the swing motor
assembly, check  that  all the  piping have
been disconnected.

I

I

NSTALL

Carry out installation in the reverse order
to removal.

Bleed the air from the swing motor.

Remove the air vent plug.
Pour in hydraulic oil until it overflows from
the port.
Tighten plug lightly.
Start the engine, run at low idling and
check oil come out from plug.
Tighten plug fully.

Confirm the hydraulic oil level and check
the hydraulic oil leak or not.

1)

(1)

(2)

(3)

ö

(4)

(5)

(6)

(7)

ö

G

GROUP  5   SWING DEVICE

2)

(1)

(2)

Η
Θ

Ι
Κ

Λ

(3)

2

1

7

3

5

6

4

8

13031GE18

21078DA03

21078DA04

A. SWING DEVICE(T3X150CHB, UP TO #1937)

8-44

2. DISASSEMBLY AND ASSEMBLY OF SWING MOTOR

STRUCTURE

1)

1

Inner ring

2

Oil seal

3

Taper roller bearing

4

Backing spring

5

Cam plate

6

Return plate

7

Piston assembly

8

Lining plate

9

Plate

10

O-ring

11

Piston

12

O-ring

13

Spring

14

Parallel pin

15

Piston

16

Cap

17

O-ring

18

Coned disc spring

19

Teflon ring

20

Bushing

21

Balance plate

22

Needle bearing

23

Snap ring

24

Cylinder

25

Housing

26

Collar

27

Plug

28

Snap ring 

29

Bypass valve assembly

30

Back up ring

31

O-ring

32

O-ring

33

Cover

34

Relief assembly

35

O-ring

36

Hexagon socket bolt

37

Time delay valve

38

O-ring

39

O-ring

40

Hexagon socket bolt

41

Check

42

Spring

43

Cap

44

Back up ring

27

4 5 6 7 8

9 10 11 12 13 14

29

30, 31

32 33

40

41

42

43

35, 44

28

26 25

24

39 23

38 22

21 20 19 18

37 36

34

35 16, 17

3

2

1

15

21072SF04

8-45

DISASSEMBLY 

Removal of relief valve assembly
Remove cap of relief valve assembly(35)
with 14mm hexagonal wrench.
Assemble removed relief valve assembly
(35) to original state when reassembling.

Removal of make up valve and bypass
valve assembly
Loosen cap(43) with 14mm hexagonal
wrench, and remove check valve(41) and
spring(42).
Remove bypass valve assembly(30) with
10mm hexagonal wrench.
Assemble removed bypass valve
assembly(29) to original state when
reassembling.

Marking at swing motor
Before disassembling motor, make a
matching mark between cover(33) and
housing(26) for easy reassembling.

(1)

ö

2)

(2)

ö

(

(

3)

Remove mounting bolts of cover
Loosen hexagon socket bolt(37) with
14mm hexagonal wrench.

(4)

25038SM02(1)

25038SM02(2)

25038SM02(3)

25038SM02(4)

8-46

Remove snap ring(23) with steel pointer
and remove inner race of needle-
bearing(22) by bearing puller.

Remove balance plate
Balance plate(21) is adhered on end
surface of cylinder(24) by oil viscosity.
Take off balance plate(21) with hands.
Assembling method of balance plate(21)
depends on cover(34).
(Band  groove and round groove of high

Â

low pressure transmission area)
Before removing, check and record
location of balance plate(21) to prevent
misassembling.

R

Removal of cover assembly
Place shaft of motor assembly to
downward and take cover(33) out.

(5)

(6)

(8)

Remove O-ring(12) from cover.

(7)

25038SM03(1)

25038SM03(2)

25038SM03(3)

25038SM03(4)

8-47

Removal of spring(13, brake area)
Remove spring(13) from piston(11).
Check and record original position of each
spring(14) for correct assembling.

Removal of brake piston
When removing piston(11) from housing
(25), there is a sliding resistance against
tightening of O-rings(10,12).   Use tap
hole(M6) on piston(11) as shown in the
picture.

Remove O-rings(10,12) from piston(11)
and housing(25).

Remove bushing(20) and coned disk spring
(18) from teflon ring(19).

(9)

(10)

(11)

(12)

25038SM04(1)

25038SM04(2)

25038SM04(3)

25038SM04(4)

8-48

Separate outer race of taper roller
bearing(3) from housing.

Remove friction plate(9) and lining plate
(8) from housing(25).

Removal of cylinder assembly
Holding end of cylinder assembly(24) with
hand, draw out cylinder assembly from
housing.
Oil seal(2) and outer race of taper roller
bearing(3) are left inside of housing.
End surface of cylinder(24) is sliding face .
So, protect the surface with a scrap of
cloth against damage.
Make a matching mark on piston hole of
cylinder(24) and piston assembly(7) to fit
piston into the same hole when
reassembling. 

Removal of oil seal
Remove oil seal(2) from housing(25) with
driver and hammer.
Do not reuse oil seal after removal.

(16)

ö

(13)

(14)

ö

ö

ö

(15)

25038SM05(1)

25038SM05(2)

25038SM05(3)

25038SM05(4)

8-49

Disassembly of cylinder assembly

Removal of inner race of taper roller
bearing(3).
After removing snap ring(28), lift out
cylinder(24) with 2 inner race of roller
bearing(3) by applying gear puller at the
end of spline in the cylinder.

Separate cam plate(5), piston assembly
(7), return plate(6) from cylinder(24).

Get cam plate(5) slide on sliding face of
piston assembly(7) and remove it.
Be cautious not to damage on sliding
face of cam plate.

Remove backing spring(4) from cylinder
(24).

This completes disassembly.

(17)

Η

Θ

Ι

ö

Κ

(210-7)  SM16

(210-7)  SM17

(210-7)  SM18

(210-7)  SM19

8-50

ASSEMBLY 

Preparation
Before reassembling, perform below
procedure.

Check each part for damage caused by
using or disassembling.   If damaged,
eliminate damage by grinding with proper
sandpaper, wash them with cleaning oil
and dry with compressed air.
Replace seal with new one.
Grind sliding face of piston assembly(7),
balance plate(21) and cam plate(5) with
sandpaper #2000.

Η

Θ
Ι

When assembling, lubricate with
specified clean hydraulic oil.
When assembling piston assembly(7) to
piston hole of cylinder(24), check
matching mark between them.

3)

(1)

Κ

Λ

(210-7)  SM20

(210-7)  SM21

(210-7)  SM22

8-51

Cylinder assembly

Lubricate grease on round area
(Contacting area with spring(4)) of
cylinder(24) and assemble spring(4).

(2)

Assemble piston assembly(7) and return
plate(6) to cylinder(24).    When
assembling, check matching mark
between them.   Before assembling,
lubricate specified hydraulic oil in piston
hole of cylinder(24).

Lubricate specified hydraulic oil on shoe
sliding face of piston assembly(7) and
assemble cam plate(5).

Insert piston assembly(7) in hole of
return plate(6).

Η

Θ

Ι

Κ

(210-7)  SM23

(210-7)  SM24

(210-7)  SM25

(210-7)  SM26

8-52

Assemble inner race of taper roller
bearing(3) to cylinder(24).

Assemble inner race(1) to cylinder(24).

Apply loctite to bearing mounting area of
inner race of cylinder(24) lightly.

Oil seal
Apply three bond of white color on outer
surface of oil seal(2) and assemble and
insert it.
Before assembling, lubricate lip of oil seal
with grease.

Λ

Μ

Ν

(

(

3)

ö

(210-7)  SM27

(210-7)  SM28

(210-7)  SM29

(210-7)  SM30