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Compact Track Loader
14. Hydraulic Pressure
High flow auxiliary troubleshooting:
4. If both high and low flow readings are low, adjust
the high pressure relief setting at the pump. (see
step 3).
5. If the low flow readings are ok, and the high are
between 3300 psi (22,750 kPa) and 3550 psi
(24,480 kPa), adjust the high pressure relief set-
ting at the pump. (see step 3).
6. If the high flow readings are less than the low flow
readings, reverse high flow direction and recheck.
If reading is within spec. in that direction, replace
the opposing high flow relief valve. (figure 14-8)
Note: Refer to pages 14-3, 14-4 for information regarding
relief valve location.
Note: High flow reliefs are set at 4650 psi (32,060 kPa). It is
not possible to test this value because the pump is equipped
with a load sense function that will not allow it to exceed
3650psi (25,170 kPa) in this circuit. Do not attempt to adjust
these reliefs. If one is found to be defective, replace it.
Low flow auxiliary troubleshooting:
7. If the low flow readings are low, check the lift arm
function readings as well. If both functions read
low, adjust the load sense relief valve as shown in
figure 14-8.
8. If the low flow circuit (only) reads low, reverse low
flow direction and recheck. If reading is within
spec. in that direction, replace the opposing low
flow relief valve. (figure 14-8)
To adjust the load sense relief setting at the
hydraulic control (loader) valve: (figure 3-4, 14-8)
a) Remove the cap covering the affected side of
the relief valve.
b) Using an allen wrench, turn the screw clock
wise to increase the setting or counter-clock
wise to reduce it until within specification.
Note: Low flow reliefs are set at 3625 psi (25,170 kPa). It is
not possible to test this value because the pump is equipped
with a load sense function that will not allow it to exceed
3300psi (22,750 kPa) in this circuit. Do not attempt to adjust
these reliefs. If one is found to be defective, replace it.
Lift Arm Pressure Check
Required Tools
Pressure Gauge 0-6000 p.s.i. (41,370 kPa)
Lift arm pressure is used to lift loads or "break-out".
Low lift arm pressure can produce a weak lift arm func-
tion while high lift arm pressure can damage lift arm
and hydraulic components.
Note: Make sure auxiliary circuit pressures are set correctly
prior to testing this function.
1. Attach a hydraulic gauge to test port C. Route the
gauge so that you or an assistant can read the
gauge while testing these functions. (figure 14-6)
2. Raise the lift arms all the way up and continue
holding the joystick even when the lift arms stop.
Record the pressure readings. Then lower the lift
arms to the stops and continue holding the joy-
stick. Record the pressure readings. Repeat this
process with the bucket dump/curl functions.
3. Check your readings against those stated below. If
your readings differ, adjustment or repair may be
necessary. (figure 14-9)
Pressures should read: (at test port C)
•
3300 +/- 100 psi (22,750 kPa) when the lift arms or
bucket are in the up/curl position.
•
3300 +/- 100 psi (22,750 kPa) when the lift arms or
bucket are in the down/dump position.
4. If any of the readings are low, reverse the function
and recheck. If reading is within specification in
that direction, replace the opposing relief valve.
14-9
14-4
Bucket
Lift Arms
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