Figure 4-3. Hydraulic Pump Test Setup.
a. Connect tachometer. Set lobe switch to 4-lobe
Start the vehicle engine and set the engine
b. Disconnect pressure hose from hydraulic pump
speed at 1450 RPM.
g. Bring the hydraulic oil to the test temperature of
and plug hose end. Connect one end of test hydraulic
130°F by gradually applying the load valve (turning
pressure hose to hydraulic pump and other end to inlet
side of flow tester. Be sure all connections are tight.
clockwise) until the fluid pressure reaches 1000 PSI.
c. Disconnect reservoir return line hose at the
hydraulic control valve and plug the valve opening.
Connect one end of the test return hose to the reservoir
Apply load valve pressure gradually as rapid
return hose and the other end to the outlet side of the
application of valve can result in "blowing out"
flow tester. Be sure all connections are tight.
the tester relief plug.
d. Set flow tester orifice selector handle on 0-30
GPM position (maximum clockwise).
h. After the hydraulic oil is brought to test
e. Turn tester load valve to fully open position by
temperature and the flow gage needle is stabilized,
turning all the way to the left (maximum
gradually reduce pressure at tester to 100 PSI by turning
load valve to the left (counterclockwise). Turn orifice
selector handle to the left (10 gal scale), stabilize flow
gage needle and record flow reading at 100 PSI tester
Load valve is capable of extremely high pressure
pressure. Flow reading should be 6 to 6.5 GPM.
and must be in the fully open position before
starting test. Do not exceed prescribed test
pressures when conducting test.