Content .. 18 19 20 21 ..

Hyundai Excavator R210LC-7. Service and repair manual - page 20

6 - 14

YES

Is the lower
speed(Bucket or
arm) within
standard level?

Does the symptom
change when
relief valves in
LH and RH
travel motors are
exchanged?

Does travel speed
change when
parking brake
spring in the
slower travel
motor is removed?

Has control valve
spool changed
over positively?

Do LH and RH
travel speeds
change over when
travel relief valves
are exchanged?

Does spool move
lightly when it is
cut off from
control spool?

YES

Brake valve is
defective.

Relief valve built
in travel motor is
faulty.

Control system is
faulty .

Control valve
spool is stuck.

Travel relief valve
is faulty.

Hydraulic pump is
broken.

External pilot
piping is clogged
or oil is leaking
from it.

Travel motor's
parking brake is
not released
properly.

Travel motor is
faulty.

Disassemble
and repair or
replace.
Disassemble
and repair.

Disassemble,
inspect and
repair.

Disassemble
and repair.

Disassemble
and repair or
replace.

Disassemble
and repair.

Disassemble
and clean.

Disassemble
and clean pilot
piping.

Disassemble
and repair.

SPEED ON ONE SIDE FALLS AND THE MACHINE CURVES

Is external pilot
pressure within
standard level?

Is leak rate of
travel motor within
standard level?

Cause

Remedy

YES

Do LH and RH
travel speeds
change when LH
and RH travel
brake valves are
exchanged?

Does the symptom
change when
front and rear
pump discharge
hoses are
exchanged?

6 - 15

YES

Is travel brake
pressure within
standard level?

Clogged

Is drain rate of
travel motor
within standard
value?

Check if parking
brake pilot line is
not clogged.

Is parking brake
friction plate
worn?

MACHINE DOES NOT STOP ON A SLOPE
Machine is pulled forward as sprocket rotates during digging operation.

Is bucket or arm
operation
possible?

Disassemble both
travel relief valves
and inspect for
any fault.

Check oil volume
in hydraulic oil
tank.

Remove dust
plug under engine
flywheel and
check that there is
no coupling
element particles.

LH AND RH TRAVEL MOTIONS ARE IMPOSSIBLE

Faulty

Hydraulic pump is
faulty.

Travel relief valve
is faulty.

Coupling at pump
connection is
broken.

Inspect according
to the procedure
"Travel does not
function at all on
one side."
However, a case
where both LH
and RH travel
motions are
disabled is
extremelyseldom
statistically.
Disassemble and
repair.

Disassemble and
repair or replace.

Disassemble and
repair.

Replenish
hydraulic oil.

Friction plate is
faulty.

Travel motor is
defective.

Brake valve is
faulty.

Disassemble
and repair.

Disassemble
and clean pilot
piping.
Disassemble
and repair.

Disassemble
and repair or
replace.

Particles present.

Short

Cause

Remedy

Cause

Remedy

None

YES

6 - 16

YES

Is travel relief
valve pressure
within standard
level?

Is travel brake
pressure within
standard level?

Is travel motor's
drain rate within
standard level?

TRAVEL ACTION IS POWERLESS

(Travel only)

MACHINE RUNS RECKLESSLY ON A SLOPE

Disassemble
and repair or
replace.

Travel motor is
faulty.

Travel brake
valve is defective.

Travel relief valve
is faulty.

Hydraulic circuit
that releases
travel parking
brake is clogged
with dirt.
Parking brake
piston in travel
motor is stuck.

Travel reduction
unit is defective.

Disassemble
and repair.

Disassemble
and repair or
replace.
Disassemble
and repair or
replace.

Disassemble
and clean.

Disassemble
and repair.

Remove parking
brake spring in
travel motor,
draw out piston
completely, refit
cover and check
if travel power
changes.

Increases

Does parking
brake piston
move lightly by
hand?

Travel brake valve
(counterbalance
valve) is faulty.

Remains

unchanged

Cause

Remedy

Cause

Remedy

6 - 17

YES

Is pilot pressure
for travel select
valve within
standard level?

Is filter in pilot
piping between
gear pump and
control valve not
clogged?

Is select valve
normal?

MACHINE MAKES A CURVED TRAVEL OR DOES NOT TRAVEL AT ALL WHEN TRAVEL AND
ATTACHMENT OPERATIONS ARE EXECUTED AT THE SAME TIME

Select valve is
faulty.

Pilot relief valve is
defective.

Gear pump is
broken.

Normal.

Repair or
replace.

Remove dirt on
pilot line filter.

Disassemble
and repair or
replace.

Disassemble
and repair.

Is gear pump
delivering oil?

Is pilot relief
valve normal?

Cause

Remedy

6 - 18

YES

Are LH/RH
operations
possible?

Does the
symptom change
when port relief
valve is replaced
with other valve?

Inspect if pilot
piping is not
clogged or oil is
not leaking from
the piping.

Disassemble
main relief valve
and check if it is
not irregular.

Are other
attachments
operatable?

Inspect oil
volume in
hydraulic oil tank.

Is MCV pilot
pressure within
standard level?

Is gear pump pilot
pressure within
standard level?

Is gear pump
delivering oil?

Particles present

YES

Faulty

Port relief valve is
faulty.

Pilot valve is
faulty.

Pilot relief valve is
faulty.

Gear pump is
broken.

Hydraulic pump is
broken.

Main relief valve
is defective.

Coupling at pump
connection is
broken.

Cylinder interior is
broken.

Control valve
spool is stuck.

Disassemble
and repair or
replace.

Disassemble
and repair.

Disassemble
and repair or
replace.
Disassemble
and repair.

Disassemble
and repair.

Disassemble
and repair or
replace.
Disassemble
and repair.

Replenish
hydraulic oil.

Disassemble
and repair.

Remove dust plug
under engine
flywheel and
check if coupling
element particles
are not present.

6. ATTACHMENT SYSTEM

BOOM OR ARM ACTION IS IMPOSSIBLE AT ALL

Short

Does control
valve spool move
lightly by hand?

Cause

Remedy

YES

6 - 19

YES

Is speed low only
in composite
operation?

Are other
attachment
speeds within
standard levels?

Does the
symptom change
when port relief
valve is replaced
with other valve?

Is pilot valve
normal?

Are LH/RH travel
speeds within
standard levels?

Is combination
of oil streams
normal at boom
hoisting and at
arm extrusion?

Are both LH/RH
travel speeds
low?

Is MCV pilot
pressure within
standard?

Does spool of flow
summation check
valve move lightly
by hand?

Flow summation
check valve spool
is stuck.

Hydraulic pump is
faulty.

Port relief valve is
faulty.

Cylinder is faulty.

Control valve spool
is stuck.

Pilot valve is
defective.
Pilot relief valve is
faulty.

Gear pump is
broken.

Pilot valve is faulty.

Normal.

Disassemble and
repair.

Disassemble and
repair or replace.

Disassemble and
repair.

Clean pilot piping
interior or repair
piping.
Disassemble and
repair.
Disassemble and
repair or replace.

Disassemble and
repair.

Adjust engine
revolution.

Clean orifice in
control valve.

Clean pilot piping
interior or repair
piping.
Disassemble and
repair.

BOOM, ARM OR BUCKET SPEED IS LOW

Does control
valve spool move
lightly by hand?

Is not MCV pilot
pressure piping
clogged or is not
there oil leakage?

Is gear pump
delivering oil?

Is pilot piping not
clogged or is oil
not leaking from
the piping?

Is MCV pilot
pressure within
standard level?

Is primary pilot
pressure within
standard level?

AIs engine
revolution within
standard level?

Is not orifice in
control valve
clogged?

Cause

Remedy

YES

6 - 20

YES

Is genuine
hydraulic oil or
equivalent being
used?

Is not hydraulic
oil temperature
high?

Does the sympto
change when
port relief valve is
replaced with
normal valve?

BOOM, ARM OR BUCKET CYLINDER EXTENDS OR CONTRACTS ITSELF AND ATTACHMENT FALLS

Normal

Port relief valve is
faulty.

Control valve's
return spring is
faulty.

Pressure
tightness
between control
valve casing and
spool is poor.
Contact surface
between poppet
and seat is poor.

Cylinder is faulty.

Disassemble
and repair or
replace.

Disassemble
and replace.

Locate the
cause of
hydraulic oil
temperature rise
and lower it to
proper level.
Replace with
genuine
hydraulic oil or
equivalent.

Disassemble
and repair.

Disassemble

Is cylinder internal
leakage within
standard level?

Abnormal

Abnormally high.

Is control valve
return spring
normal?

Disassemble and
inspect check
valve in hydraulic
circuit and check
for any fault.

Cause

Remedy

YES

6 - 21

YES

Is RH travel
possible?

Is MCV pilot
pressure within
standard level?

Does the
symptom change
when main relief
valves are
exchanged?

Does the
symptom change
when port relief
valve is replaced
with other valve?

ONLY BUCKET OPERATION IS TOTALLY IMPOSSIBLE

Port relief valve is
defective.

Cylinder interior is
broken.

Control valve
spool is stuck.

Pilot valve is
faulty.

Main relief valve
is faulty.

Hydraulic pump is
broken.

Disassemble
and repair or
replace.
Disassemble
and repair.

Disassemble
and repair.

Adjust pressure,
repair or
replace.

Disassemble
and repair.

Does control
valve spool
move smoothly
by hand?

Does the
symptom change
when hydraulic
pump's discharge
hoses are
exchanged?

BOOM, ARM OR BUCKET POWER IS WEAK

Is relief pressure
in main relief
valve within
standard level?

Is cylinder
internal leakage
within standard
level?

Is relief pressure
in port relief
valve within
standard level?

Cylinder is faulty.

Port relief valve is
faulty.

Main relief valve
is defective.

Check according
to the procedure
in Item "Speed is
low".

Disassemble
and repair.

Adjust pressure,
repair or replace.

Cause

Remedy

Cause

Remedy

YES

6 - 22

YES

Is boom foot pin
greased
sufficiently?

Boom foot pin
has run out of
grease.

Frictional noise
occurs between
the sliding faces
of boom
cylinder's oil
seal and boom
proper.

Supply grease
to it.

BOOM MAKES A SQUEAKING NOISE WHEN BOOM IS OPERATED

Frictional

noise will
disappear if
they are kept
used.

If seizure is in
an initial stage,
supply sufficient
grease.
If seizure is in
a grown state,
correct it by
paper lapping
or with an oil
stone.

Cause

Remedy

6 - 23

HOW TO CHECK INTERNAL BOOM CYLINDER LEAKAGE

Raise bucket OFF the ground by retracting
the arm cylinder rod.

If oil leaks from piping side and boom
cylinder rod is retracted there is an internal
leak in the cylinder.
If no oil leaks from piping side and boom
cylinder rod is retracted, there is an internal
leak in the control valve.

Disconnect hose(A) from rod side of boom
cylinder and drain oil from cylinders and
hose.(Put cups on piping and hose ends)

Lower the bucket teeth to the ground with
bucket cylinder fully retracted and arm
cylinder rod retracted almost in full.

29076TS01

(210-7) 6-20(2)

29076TS01

6 - 24

GROUP 3 ELECTRICAL SYSTEM

1. WHEN STARTING SWITCH IS TURNED ON, MONITOR PANEL DISPLAY DOES NOT APPEAR

Before disconnecting the connector, always turn the starting switch OFF.
Before carrying out below procedure, check all the related connectors are properly inserted and

short of fuse No.7.

After checking, insert the disconnected connectors again immediately unless otherwise specified.

YES

Check voltage
between CN-5(8)
,(3) and chassis

Check voltage
between CN-56
(1) and chassis

Starting switch : ON
Voltage : 20~32V

Cause

Remedy

Defective clucter

Disconnection in
wiring harness or
poor contact
between CN-5(8),
(3)-CN-56(1)

Disconnection in
wiring harness or
poor contact
between CN-5(8),
(3)-and fuse No.7

Replace

Repair or
replace
(After clean)

21076ES51

6 - 25

CLUSTER

POWER IG(24V)

GND

CN-56

CN-5

CN-50

*4V

*12V

CONTROLLER

YES

*4V

*12V

Check voltage

2. COMMUNICATION ERROR "Co : Er" FLASHES ON THE CLUSTER

Before disconnecting the connector, always turn the starting switch OFF.
Before carrying out below procedure, check all the related connectors are properly inserted.
After checking, insert the disconnected connectors again immediately unless otherwise specified.

Cause

Remedy

Defective controller

Disconnection in
wiring harness or
poor contact
between CN-56
(3,4) CN-5(10,11)

Disconnection in
wiring harness or
poor contact
between CN-5
(10,11)-CN-50
(29,30)

Replace

Repair or replace
(After clean)

KEY ON

Check voltage
between CN-5
(10,11)and
chassis

YES

Check voltage
between CN-56
(3,4) and chassis

29076ES02

6 - 26

3. BATTERY CHARGING WARNING LAMP LIGHTS UP

(Starting switch : ON)

Cause

Remedy

Defective controller

Disconnection in
wiring harness or
poor contact
between CN-51(9)
-CN3(6),(3)

Disconnection in
wiring harness or
poor contact
between
CN-3(6),(3)-altern-
ator terminal "I"

Defective alternator

Replace

Repair or replace
(After clean)

Replace

YES

Voltage : 20~32V
Engine : Running

Check voltage
between alternator
terminal "I" and
chassis

Check voltage
between CN-3
(6),(3) and
chassis

Check voltage
between CN-51
(9) and chassis

21076ES52

6 - 27

4. WHEN COOLANT OVERHEAT WARNING LAMP LIGHTS UP

(Engine is started)

Cause

Remedy

Coolant overheat
(110 C

2 C )

Defective temp
sensor

Short circuit in
wiring harness

Defective Controller

Check engine
cooling system

Replace

Repair or replace
(After clean)

Replace

Starting switch : ON
Engine : Start

Does display go
off when
disconnect CD-8?

Resistance

between CN-51
(31,33) is 0~1 ?

YES

Disconnect CN-51
KEY OFF

Disconnect CD-8

Resistance
between CD-8
(1,2) is in range
of 120~150 ?

21076ES53

6 - 28

5. WHEN AIR CLEANER WARNING LAMP LIGHTS UP

(Engine is started)

Cause

Remedy

Clogged air filter or
defective switch

Short circuit in
wiring harness

Defective controller

Check filter or
replace switch

Repair or replace
(After clean)

Replace

CN-50

AIR CLEANER SWITCH

CD-10

CONTROLLER

Starting switch : ON
Engine : Start

Does display go
off when
disconnect CD-
10?

Check resistance
between CN-51
(16) and chassis

YES

Starting switch : OFF
Disconnect CN-51

YES

MAX 1

MIN 1M

Check resistance

25036EL05

6 - 29

6. WHEN ENGINE OIL PRESSURE WARNING LAMP LIGHTS UP

(Engine is started)

Cause

Remedy

Engine oil leakage,
or defective switch

Defective controller

Disconnection in
wiring harness or
poor contact
between
CN-51(4)-CD-18

Check engine oil
level or replace
switch

Replace

Repair or replace
(After clean)

ENGINE OIL PRESSURE SWITCH

CD-18

CN-2

CN-51

CONTROLLER

YES

Starting switch : ON
Engine : Start

Does display go off
when disconnect
CD-18?

Check resistance
between CN-51
(4) and chassis

Starting switch : OFF
Disconnect CN-51

YES

MAX 1

MIN 1M

Check resistance

29076ES03

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