Service manual

W–2006–0284
When the engine is running during service, the
steering levers must be in neutral and the
parking brake engaged. Failure to do so can
cause injury or death.
MAIN RELIEF VALVE
Checking The Main Relief Valve
The tools listed will be needed to do the following
procedure:
MEL10003 – Hydraulic Tester
MEL10006 – Hydraulic Test Kit
Turn the key switch to the OFF position, as the engine
stops running, turn the key switch all the way to the left to
release the hydraulic pressure at the front auxiliary quick
couplers.
Lift and block the loader. (See Page 1–1.)
Connect the IN port of the hydraulic tester to the female
quick coupler on the loader [A].
Connect the OUT port of the hydraulic tester to the male
quick coupler on the loader [A].
The hydraulic tester must be in the fully open
position before you start the engine.
I–2024–0284
Put jackstands under the front axles and rear
corners of the frame before running the engine
for service. Failure to use jackstands can allow
the machine to fall or move and cause injury or
death.
W–2017–0286
Start the engine and run at low engine idle RPM. Push the
mode switch (Item 1) [B] two times (on the instrument
panel) to engage the front auxiliary hydraulics, the light
(Item 2) [B] will come ON.
Push the button (Item 1) [C] for fluid pressure to the quick
couplers.
Watch the flow meter on the hydraulic tester to make sure
the flow is correct. Increase the engine speed to full RPM.
There should be 18.0 GPM (68 L/min.) free flow. Turn the
restrictor control, on the tester, until the main relief valve
opens. The correct pressure for the main relief is
2700–2750 PSI (18617–18961 kPa).
If the relief pressure is not correct, stop the engine.
Replace or adjust the main relief valve. (See Page 2–15.)
A
P–05061
C
P–00387
Right
Steering
Lever
Control
1
P–00391
Left
Steering
Lever
Control
–2–20–
853, 853H Loader
Service Manual
B
B–13443
1
2