Service manual

Groundsmaster 3280--D/3320 Hydraulic SystemPage 5 -- 19
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 Special Tools
section in this Chapter).
CAUTION
Failure to use gauges with recommended pres-
sure (psi) rating as listed in test procedures
could result in damage to gauge and possible
personal injury from leaking hot oil.
Before Performing Hydraulic Tests
All obvious areas such as oil supply, filter, binding link-
age, loose fasteners or improper adjustments must be
checked before assuming that a hydraulic component is
the source of the problem being experienced.
Precautions For Hydraulic Testing
Before disconnecting or performing any work
on the hydraulic system, all pressure in the
system must be relieved by stopping the engine
and lowering or supporting the cutting deck or
other implement.
Keep body and hands away from pin hole leaks
or nozzles that eject hydraulic fluid under high
pressure. Use paper or cardboard, not hands, to
search for leaks. Hydraulic fluid escaping under
pressure can have sufficient force to penetrate
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. Gangrene may result from such
an injury.
WARNING
1. Thoroughly clean the machine before disconnecting
or disassembling any hydraulic components. Always
keep in mind the need for cleanliness when working on
hydraulic equipment. Contamination will cause exces-
sive wear of hydraulic components.
2. Put caps or plugs on any hydraulic lines left open or
exposed during testing or removal of components.
3. The engine must be in good operating condition. Use
a tachometer when making a hydraulic test. Engine
speed will affect the accuracy of the hydraulic test read-
ings.
4. To prevent damage to tester or components, the inlet
and the outlet hoses must be properly connected, and
not reversed (when using tester with pressure and flow
capabilities).
5. To minimize the possibility of damaging compo-
nents, completely open load valve in hydraulic tester
(when using tester w ith pressure and flow capabilities).
6. Install fittings finger tight, far enough to insure that
they are not cross--threaded, before tightening with a
wrench.
7. Position the tester hoses so that rotating machine
parts will not make contact w ith them and result in hose
or tester damage.
8. Check and adjust the oil level in the reservoir (front
axle) after connecting hydraulic test equipment.
9. Check the control linkage for improper adjustment,
binding or broken parts.
10.All hydraulic tests should be made with the hydraulic
oil at normal operating temperature.
11.After testing is completed, check oil level in reservoir
(front axle) and adjust if necessary. Also, make sure that
no leakage from hydraulic components exist.
Hydraulic
System