Groundsmaster 3505--D Hydraulic SystemPage 4 -- 25
Testing
The most effective method for isolating problems in the
hydraulic system is by using hydraulic test equipment
such as pressure gauges and flow meters in the circuits
during various operational checks (See the Special
Tools section in this Chapter).
Before Performing Hydraulic Tests
IMPORTANT: All obvious areas such as oil supply,
filter, binding linkages, loose f asteners or improper
adjustments mustbe checked beforeassuming that
a hydraulic componentis the source of theproblem.
Precautions for Hydraulic Testing
CAUTION
Failure to use gauges with expected pressure
(psi) rating as listed in test procedures could re-
sult indamage to thegauge andpossible person-
al injury from leaking hot oil.
CAUTION
All t esting should be performed by two (2)
people. One person should be in the seat tooper-
ate the machine and the other should read and
record test results.
WARNING
Keep bodyand hands away frompin hole leaks
or nozzles that eject hydraulic fluid under high
pressure. Do not use hands to search for
leaks; use paper or cardboard. Hydraulic fluid
escaping under pressure can have sufficient
force to penetrate the skin and cause serious
injury. If fluid is injected into the skin, it must
be surgically removed within a few hours by a
doctor familiar with this type of injury. Gan-
grene may result from such an injury.
1. Clean machine thoroughly before disconnecting or
disassembling any hydraulic components. Always keep
in mind the need for cleanliness when working on hy-
draulic equipment. Contamination can cause excessive
wear or binding of hydraulic components.
2. Before testing, check control linkages for improper
adjustment, binding or broken parts.
3. All hydraulic tests should be made with the hydraulic
oil at normal operating temperature.
WARNING
Before disconnecting or performing any work
on the hydraulic system, all pressure in the
system must be relieved. See Relieving Hy-
draulic System Pressure in the General Infor -
mation section.
4. Put metal caps or plugs on any hydraulic lines left
open or exposed during testing or component removal.
5. When using hydraulic tester (pressure and flow), the
inlet and the outlet hoses must be properly connected
and not reversed to prevent damage to the hydraulic
tester or components.
6. Install hydraulic fittings finger tight and far enough to
make surethat theyare notcross--threaded beforetight-
ening them with a wrench.
7. Position tester hoses to prevent rotating machine
parts from contacting and damaging the hoses or tester.
8. After connecting test equipment, check oil level in
the hydraulic tank to make sure that oil level is correct.
9. When using hydraulic tester (pressure and flow),
open testerload valve completely beforestarting engine
to minimize the possibility of damaging components.
10.The engine mustbe in goodoperating condition. Use
a phototac when performing a hydraulic test. Engine
speed can affect the accuracy of the tester r eadings.
Check actual speed of the pump when performing hy-
draulic flow tests.
11.If a traction circuit problem exists, consider perform-
ing one or more of the following tests: Traction Circuit
Working Pressure, Charge Relief Valve Pressure, Pis-
ton Pump (P3) Flow & Traction Relief Pressure and/or
Wheel Motor Efficiency Tests.
12.If a cutting circuit problem exists, consider perform-
ing one or more of the following tests: Cutting Deck Cir-
cuit Pressure, Manifold Relief Valve (R1) Pressure,
Logic (Counterbalance) Valve (LC1) Pressure, Gear
Pump (P1) Flow and/or Deck Motor Efficiency Tests.
13.If asteering orlift circuitproblem exists,consider per-
forming one or more of the following tests: Steering and
Lift Relief Pressure, Gear Pump (P2) Flow and/or Steer-
ing Control Valve Tests.
Hydraulic
System