Relief Valve - Flow Test (H.50.C.17 - F.40.A.45) - Case 445CT Repair Manual

Relief valve - Flow test (H.50.C.17 - F.40.A.45)

435, 445, 445CT
Prior operation: Relief valve - Flow test (A.10.A.16 - F.40.A.45)
1. Start the engine and run the engine at 2300 r/min
(rpm).
2. Hold the bucket control lever in the ROLLBACK
position and close the pressure valve on the
flowmeter until the pressure gauge indicates 124
bar (1800 psi). Adjust the engine speed to keep the
engine running at 2300 r/min (rpm). Read the flow
gauge and record the reading as test number 7.
3. Hold the bucket control lever in the DUMP position
and adjust the pressure valve on the flowmeter
until the pressure gauge indicates 124 bar (1800
psi). Adjust the engine speed to keep the engine
running at 2300 r/min (rpm). Read the flow gauge
and record the reading as test number 8.
NOTE: Understanding the results of the tests are outlined
in the steps below.
4. Refer to Hydraulic pump - Flow test (A.10.A.20
- F.40.A.45) If the flow indication for a circuit was
approximately the same as the flow indication at the
same pressure in Test Number 1 of the Hydraulic
Pump Flow Test , the circuit is good.
5. If the flow indication for a circuit was more than
3.8 L/min (one gpm) less than the flow indication
at the same pressure in Hydraulic pump - Flow
test (A.10.A.20 - F.40.A.45) Test Number 1, there
is leakage in that circuit.
6. Leakage in the tilt circuits can be caused by any of
the following problems:
A. Damaged or worn packing in one or both of the
tilt cylinders.
B. Damaged or worn spool or spool bore in the
loader control valve.
C. Self-leveling valve (if equipped) is sticking or has
worn spools.
D. Defective circuit relief valves.
E. Inadequate control spool travel.
7. If the flow indication for every circuit tested was
more than 3.8 L/min (one gpm) less than the flow
indication at the same pressure in test number. 1,
there is leakage at a point common to the entire
system. A probable cause is a damaged or worn
main relief valve or seals.
WORKING ARM - SINGLE ARM TOOL ATTACHMENT Tilt
1 04/05/2005
H.50.C / 23