SkyTrak 8042 Service Manual - Manual (Page 450)

8.35 Model 8042, 10042, 10054 Legacy Rev. 10/03
Hydraulic System
NOTE:
When checking pressures in
circuits, refer to Section 8.7,
“Hydraulic System Testing,” for
correct pressure readings.
Not
OK
Not
OK
If the attachment tilt cylinder
extends slowly, check cable
connections at main control
Repair/replace slave cylinder(s).
Not
OK
Check packing in attachment
tilt cylinder.
Repair/replace attachment
tilt cylinder.
If OK
Not
OK
Check the pilot-operated check
valve on the attachment tilt cylinder. Replace pilot-operated check valve.
Repair/replace cable connections.
Ensure attachment tilt section of
main control valve is functioning.
Isolate and check each slave
cylinder for packing leaks.
If OK
Not
OK
Check main relief pressure on
main control valve.
Adjust/repair/replace relief valve
on main control valve.
If OK
If OK
If OK
Before troubleshooting any
hydraulic circuit, ALWAYS
begin by checking the
following:
1. Hydraulic oil level in the
reservoir
2. All hoses, tubes, fittings
for leaks, kinks,
interference, etc.
3. Air in the lines
Not
OK
Check pump flow. Repair/replace pump.
Not
OK
If the attachment tilt cylinder
drifts and does not hold load,
check the counterbalance valve
on the attachment tilt cylinder.
If OK
Not
OK
Isolate and check packing in each
slave cylinder.
Repair/replace slave cylinder(s).
Replace counterbalance valve.
If OK
Not
OK
Check packing in attachment
tilt cylinder.
Repair/replace attachment
tilt cylinder.
NOTE:
Refer to Section 2.5.4,
“Performance Specifications,”
for
approximate cylinder cycle
times. The operation of the
system function should
approximate the times listed.