Hyundai HL955 Manual page 509

Item
Boom cylinder leakage
check
H e a t hy d r a u l i c o i l t o
operating temperature.
Bucket cylinder leakage
check
H e a t hy d r a u l i c o i l t o
operating temperature.
Check valve of safety
valve leakage check
H e a t hy d r a u l i c o i l t o
operating temperature.
Pilot control valve
(RCV lever) check
Description
Dump bucket until teeth or cutting
edge is perpendicular to the
ground.
Raise boom until cutting edge is
about 1 m (3 ft) above ground.
Stop engine. Measure drift from
tooth or cutting edge to ground for
1 minute.
Wait 10 minutes.
Measure drift from tooth or cutting
edge to ground for 1 minute.
LOOK : Compare the drift rate
between the first measurement
and the second measurement.
Raise bucket about 1 m (3 ft) off
ground with bucket level.
Stop engine. Place a support
under boom.
Measure drift from tooth or cutting
edge to ground for 1 minute.
Wait 10 minutes.
Measure drift from tooth or cutting
edge to ground for 1 minute.
LOOK : Compare the drift rates
between the first measurement
and the second measurement.
Put bucket level and position
about 1.2 m (4 ft) above ground.
Place a piece of tape on cylinder
rod at least 51 mm (2 in) from rod
guide.
Run engine at low idle in safety-
release position.
LOOK : Bucket must not drift up.
Stop engine. Turn key switch to
OFF position.
Move control lever to all positions
and then release.
LOOK : Lever must return to
neutral when released from all
positions.
6-44
Service action
OK
Drift is approximately the
same between first and
second measurement.
Repair loader control
valve or circuit relief valve.
NOT OK
If drift is considerably less
on second measurement,
repair cylinder.
OK
Drift is approximately the
same between first and
second measurement.
Repair loader control
valve or circuit relief valve
at page 6-57.
NOT OK
Drift is considerably less
on second measurement.
Repair cylinder.
OK
Check complete.
NOT OK
Check or replace safety
valve.
OK
Check completed.
NOT OK
Repair pilot control valve.