Hyundai R 160 LC-3, Service Manual

Page: 229 / 459

6 - 10
SWING SPEED IS LOW
2)
Is the trouble in
one direction or in
both direction?
Clogged or oil leak.
NO
YES
NO
NO
YES
NO
YES
NO
NO
YES
NO
YES
YES
NO
YES
Does swing control
valve spool move
smoothly by hand?
Is not pilot piping
clogged or is not it
leaking oil?
Is MCV pilot
pressure within
standard level?
Is gear pump pilot
pressure within
standard level?
Is swing motor's
drain rate within
standard value?
YES
NO
YES
NO
NO
YES
NO
YES
NO
YES
Is MCV pilot
pressure same on
LH and RH sides?
Is Arm speed
within standard
value?
Cause Remedy
Swing port relief
valve is faulty.
Swing control valve
spool is stuck.
Pilot valve or shuttle
valve is faulty.
ڞ
Swing control valve
spool is stuck.
ڟ
ڠ
Swing motor is
broken.
Pilot valve or shuttle
valve is faulty.
Pilot relief valve is
defective.
Gear pump is
broken.
Main relief valve
faulty.
Hydraulic pump is
broken.
Shuttle valve is
faulty.
Pilot relief valve is
faulty.
Gear pump is
faulty.
Disassemble and
repair or replace.
Disassemble and
repair.
Clean pilot piping
interior or repair
piping.
Disassemble and
repair.
Disassemble and
repair.
Disassemble and
repair.
Disassemble and
repair.
Clean pilot piping
interior or repair
piping.
Disassemble and
repair or replace.
Disassemble and
repair.
Main relief valve
pressure
resetting or repair.
Disassemble and
repair.
Repair or replace.
Repair or replace.
Repair or replace.
ڞ
ڟ
ڠ
Does swing control
valve spool move
lightly by hand?
Check that pilot
piping is not
clogged or oil is not
leaking from it?
Clogged or oil leak.
Is gear pump
delivering oil?
Does the symptom
change when front
and rear pump
discharge hoses
are exchanged?
Is gear pump
output pressure
within standard
level?
Is safety valve pilot
pressure within
standard level?
Both directions
Single direction
Is main relief valve
setting pressure
normal?