Hyundai HL955 Manual page 525

8. BOOM AND BUCKET CYLINDER LEAKAGE TEST
·
SPECIFICATION
Oil temperature
Engine speed
Maximum leakage 15 mℓ/min (1/2 oz/min)
·
GAUGE AND TOOL
Temperature reader
Stop watch
Measuring container
1) Fasten temperature sensor to head end
port of cylinder to be tested. Cover sensor
with a shop towel.
2) Heat hydraulic oil to specifications (see
hydraulic oil warm up procedure in this
group).
Never work under raised equipment
unless it is supported with a hoist or
support stands.
3) Full extend the cylinder to be tested. If
testing the boom cylinders, restrain boom in
the fully raised position using a hoist or a
stand.
※
Check cylinders for leakage in the fully
extended position only. In the retracted
position contacts the end of the cylinder
and seals off piston seal leakage.
4) Remove and plug cylinder rod end hose or
line.
5) Run engine at slow idle. Activate control
lever to extend cylinder for 1 minute over
relief while measuring leakage for open
port.
If leakage is within specification, excessive
cylinder drift is caused by leakage in the
loader control valve or circuit relief valve.
45±5˚C (113±9˚ F)
Low idle
6-60
(770-3ATM) 6-56