Textron Jacobsen Super LF 1880 Fairway Mower with ROPS, Инструкции по обслуживанию и ремонту

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HYDRAULICS
8O-51
SECTION 8O. HYDRAULIC INSTRUMENT TESTS
GENERAL
The tests in this section are provided as a means of
isolating problems in the hydraulic system
This section uses two test methods to identify a prob-
lem or to evaluate a hydraulic circuit. The first test is a
pressure test. The pressure test determines how much
force (pounds per square inch – psi (kPa)) is being
used to force the available hydraulic oil through the cir-
cuit. The second test (flow) determines how much oil is
flowing through the circuit and how long it takes for the
oil to flow through the circuit (gallons per minute – gpm
(lpm)).
During the pressure test a pressure gauge is installed
in-line with the component pressure inlet. The test
determines how much pressure is being exerted on the
oil flowing to the component.
In the flow test a flow/pressure tester is installed in-line
with the component to determine how much (gpm/lpm)
oil is flowing to and from the component and how much
force (psi/kPa) is being exerted on the oil.
The flow test is more complete and can isolate a prob-
lem within a circuit.
Make sure the mower is secured and cannot roll. If
interlock systems are bypassed, exercise caution when
performing each test.
Follow the instructions carefully and completely. Plug
lines and cap ports are directed.
A test record has been provided at the end of this sec-
tion. Make copies of the record for future use. Use the
form to record test results.
NOTE:
An in-line tester (Figure 8O-1) is used in this sec-
tion to measure oil flow. When using a tester with
variable gpm settings, make sure tester is set for
the proper flow range to avoid damage to the
tester. Record all readings obtained during the
test. Perform all tests at the same engine speed
(rpm) and the hydraulic oil at operating tempera-
ture.
Figure 8O-1. In-Line Flow Tester
NOTE:
The instrument tests described in this section are
intended as a guide only and may not include
every problem encountered within a hydraulic sys-
tem Contact your local Jacobsen dealer for addi-
tional information and assistance.
PRESSURE TESTS
The pressure tests are frequently inconclusive in isolat-
ing a faulty component. A flow test is recommended for
isolating a problem within a circuit. The pressure tests
are useful in determining the pressure settings of pres-
sure relief valves.
CHARGE PRESSURE TEST
1. Shut down the engine.
2. Install a 200-psi (1379 kPa) pressure gauge and
in-line tee between the steering unit inlet and the
supply hose, see Figure 8O-2.
CAUTION
If interlock safety features are bypassed during a
test, use extreme caution when performing tests and
make sure the interlock system is functional after the
test.
CAUTION
When using a plug to block a pressure line the plug
must be able to withstand the pressure developed in
the circuit.
Load
Valve
IN OUT
8O