Allied Construction Products, LLC www.alliedcp.com
TM576981_HP700B_18feb
19
12.0 Technical Information
12.1 Testing the Hydraulic Circuit
The Allied Ho-Pac will provide efficient and reliable
results if the motor is operated at the accepted oil
flow rate and turns at the optimal speed.
It’s important to measure the machine's hydraulic
performance prior to using the Allied work tool. The
performance of the work tool is impaired by a
hydraulic system that is not operating correctly or set
outside the accepted specifications.
Tools required to complete these tests include a flow
meter and pressure gages. Record the test
measurements in the worksheet provided below.
Tests are performed under varied conditions,
including temperature, work mode, engine speed and
load. Use test results to confirm that the hydraulic
circuit is properly calibrated and set in accordance to
the accepted specifications listed in the technical
data section of this manual.
Work Mode
Engine RPM
Flow [GPM]
Load [PSI]
Oil Temp [ºF]
Relief [Crack]
Relief [Static]
Return [PSI]
0
1000
1500
1800
2000
2200
2400
2600
2800
3000
3200
3400
CAUTION
Only qualified personnel, having knowledge of the
machine’s systems, proper test equipment and tools
should attempt testing and adjustments. Before
starting, make sure the circuit to be tested has a
relief valve. Open restrictor valve on flow meter.
Procedures can vary depending on specifics of your
equipment. Follow the instructions provided by the
manufacturer of the carrier and flow meter when
testing.
Work Mode
– Set to correct position (if equipped).
Engine RPM
– Set to normal operating speed
Flow [GPM]
– Record measured flow at each load
pressure
Load Pressure [PSI]
– Steadily increase load with
restrictor valve on the flow meter
Oil Temperature
– Oil temperature must be at
normal operating temperature while testing. Stop test
if temperature exceeds 176
q
F (80
q
C)
Relief Pressure [Crack]
– Slowly close restrictor
valve until pressure gage indicates relief valve has
cracked open.
Relief Pressure [Static]
– After cracking pressure is
reached, further adjust restrictor valve until flow gage
indicates relief valve is fully open.
Return Pressure [PSI]
– Record the pressure
measured in the return line. Measuring point for gage
must be located near the motor's outlet port.
If troubleshooting, include all associated parts of the
attachment circuit to exclude any possibility of a
collapsed hose or other fault or malfunction.