8.105
Model 644E-42/944E-42
Rev. 6/04
Hydraulic System
NOTE:
When checking pressures in
circuits, refer to Section 8.7,
“Hydraulic System Testing,” for
correct pressure readings.
If the attachment tilt
cylinder extends slowly.
Not
OK
Isolate and check each slave
cylinder for seal leaks.
Repair/replace
slave cylinder(s).
Not
OK
Check pilot pressure at “PPG”
port of accumulator charge/
secondary function valve.
Adjust/repair/replace
pressure reducing cartridge
on accumulator charge/
secondary function valve.
Not
OK
Check counterbalance valve
on attachment tilt cylinder.
Replace the
counterbalance valve.
Not
OK
Check pilot operated check
valve on attachment tilt
cylinder.
Replace the pilot operated
check valve.
Not
OK
Check port relief at main
control valve
Replace the relief valve on
attachment tilt section of main
control valve.
Not
OK
Check seals in
attachment tilt cylinder.
Repair/replace
attachment tilt cylinder.
Not
OK
Inspect pump. Refer to
Hydraulic Testing
Check the cycle times for
boom LIFT and boom
EXTEND to determine pump
performance. Pump flow
directly controls these cycle
times. Refer to Section 2.5.6,
for correct cycle times.
If OK
If OK
If OK
If OK
If OK
If OK
Not
OK
Replace counterbalance and/
or pilot-operated check valves
on the attachment tilt cylinder.
Check counterbalance and
pilot-operated check valves.
Not
OK
Check seals in attachment
slave cylinder.
Repair/replace slave cylinder.
If OK
Not
OK
If the attachment tilt
cylinder drifts or reacts
slowly, check the seals on
the attachment tilt cylinder.
Repair/replace attachment
tilt cylinder.
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
Summary of Contents for 944E-42
Page 1: ......
Page 2: ......
Page 14: ...Safety Practices 1 8 Model 644E 42 944E 42 Rev 6 04 This Page Intentionally Left Blank...
Page 102: ...Boom 3 56 Model 644E 42 944E 42 Rev 6 04 This Page Intentionally Left Blank...
Page 139: ...4 37 Model 644E 42 944E 42 Rev 6 04 Cab and Covers This Page Intentionally Left Blank...
Page 144: ...Cab and Covers 4 42 Model 644E 42 944E 42 Rev 6 04 This Page Intentionally Left Blank...
Page 265: ...8 15 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 269: ...8 19 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 273: ...8 23 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 277: ...8 27 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 281: ...8 31 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 285: ...8 35 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 289: ...8 39 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 293: ...8 43 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 297: ...8 47 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 301: ...8 51 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 407: ...8 157 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 425: ...8 175 Model 644E 42 944E 42 Rev 6 04 Hydraulic System This Page Intentionally Left Blank...
Page 501: ...8 251 Model 644E 42 944E 42 Rev 6 04 Hydraulic System MT1950 2 3 4 5 6 7 8 5 5...
Page 507: ...8 257 Model 644E 42 944E 42 Rev 6 04 Hydraulic System MT1950 1 2 3 4 5 6 7 4 4...
Page 508: ...Hydraulic System 8 258 Model 644E 42 944E 42 Rev 6 04 This Page Intentionally Left Blank...
Page 525: ...9 17 Model 644E 42 944E 42 Rev 6 04 Electrical System This Page Intentionally Left Blank...
Page 554: ...Electrical System 9 46 Model 644E 42 944E 42 Rev 6 04 This Page Intentionally Left Blank...
Page 759: ...10 3 Model 644E 42 944E 42 Rev 6 04 Stabil TRAK System This Page Intentionally Left Blank...
Page 765: ...10 9 Model 644E 42 944E 42 Rev 6 04 Stabil TRAK System This Page Intentionally Left Blank...
Page 785: ...10 29 Model 644E 42 944E 42 Rev 6 04 Stabil TRAK System This Page Intentionally Left Blank...
Page 800: ...Stabil TRAK System 10 44 Model 644E 42 944E 42 Rev 6 04 This Page Intentionally Left Blank...
Page 832: ...Transfer Carriage 11 32 Model 644E 42 944E 42 Rev 6 04 This Page Intentionally Left Blank...
Page 840: ...12 8 Model 644E 42 944E 42 Rev 6 04 Index...
Page 841: ...Accident Prevention Tags OS2180 8990403 Origin 5 00 Accident Prevention Tags...
Page 842: ...Accident Prevention Tags OS2180 8990403 Origin 5 00...
Page 843: ......
Page 844: ......