TM 5-3895-383-24
Flow loss that is expressed as a percentage of pump flow is
used as a measure of pump performance.
Table 3
Method of determining percent of flow loss:
Flow loss (L/min or US gpm)
Percent
Pump flow at
X 100 =
of flow
690 kPa (100 pi)
loss
Table 4
Example of determining percent of flow loss:
20.8 L (5.5 US gal)
X 100 =
9.5%
217.6 L/min (57.5 US gpm)
If the percent of flow loss is greater than 10% the pump
performance is inadequate.
NOTE:
The values in the examples are not set values for
any specific pump or for any specific pump
condition. See the Specification for your machine
for the pump flow of a new pump at 690 kPa (100
psi) and at 6900 kPa (1000 psi).
Machine Test
Install a flow meter. Run the engine at high idle. Measure the
pump flow at 690 kPa (100 psi) and at 6900 kPa (1000 psi).
Use these values in the following formula.
Table 5
Pump flow at 690 kPa
(100 psi)
Pump flow at 6900 kPa
-
(1000 psi)
Percent of
Pump flow at 690 kPa
X 100 = flow loss
(100 psi)
Bench Test
If the bench test can be performed at 6900 kPa (1000 psi) and
at full pump rpm, determine the percent of flow loss by using
the above formula.
If the bench test cannot be performed at 6900 kPa (1000 psi)
or at full pump rpm, run the pump shaft at 1000 rpm. Measure
the pump flow at 690 kPa (100 psi) and at 6900
kPa (1000 psi). Use these values in the top portion of the
following formula. For the bottom part of the formula, run the
pump shaft at 2000 rpm. Measure the pump flow at 690 kPa
(100 psi).
Table 6
Pump flow at 690 kPa
(100 psi)
Pump low at 6900 kPa
-
(1000 psi)
Percent of
Pump flow at 690 kPa
X 100 = flow loss
(100 psi) and at 2000 rpm
Charge Relief Valve - Test and Adjust
SMCS Code: 5117-025-PX; 5117-081-PX
Table 7
Required Tools
Part Number
Description
Qty
4C-6500
Digital Thermometer
1
4C-4892
ORFS Fittings Group
1
9U-7400
Multitach
1
Personal injury or death can result from sudden machine
movement.
Sudden movement of the machine can cause injury to
persons on or near the machine.
To prevent injury or death, make sure that the area around
the machine is clear of personnel and obstructions before
operating the machine.
NOTICE
Care must be taken to ensure that fluids are contained
during performance of inspection, maintenance, testing,
adjusting and repair of the product Be prepared to collect
the fluid with suitable containers before opening any
compartment or disassembling any component containing
fluids.
Refer to Special Publication, NENG2500, "Caterpillar Tools
and Shop Products Guide" for tools and supplies suitable
to collect and contain fluids on Caterpillar products.
Dispose of all fluids according to local regulations and
mandates.
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