Service Manual

Multi Pro 5800Hydraulic System Page 5 − 24
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 hydrau-
lic circuits during various operational checks (see the
Special Tools section in this Chapter).
Before Performing Hydraulic Tests
IMPORTANT: All obvious areas such as hydraulic
oil supply, oil filter, binding linkages, loose fasten-
ers or improper adjustments must be checked be-
fore assuming that a hydraulic component is the
source of a hydraulic problem.
WARNING
Before performing any work on the hydraulic
system, system pressure must be relieved and
all rotating machine parts must come to a stop.
Turn ignition switch OFF and remove key from
switch. When engine has stopped rotating, oper-
ate all hydraulic controls to relieve hydraulic
system pressure.
Precautions for Hydraulic Testing
CAUTION
Failure to use gauges with recommended pres-
sure (PSI) rating as listed in test procedures
could result in damage to the gauge and possible
personal injury from leaking hot oil.
WARNING
Keep body and hands away from pin 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 escap-
ing under pressure can have sufficient force to
penetrate the skin and cause serious injury. If
fluid is injected into the skin, it must be surgical-
ly removed within a few hours by a doctor famil-
iar with this type of injury. Gangrene may result
from such an injury.
CAUTION
All testing should be performed by two (2)
people. One person should be in the seat to oper-
ate the machine and the second person should
read and record test results.
1. Clean machine thoroughly before disconnecting or
disassembling any hydraulic components. Always keep
in mind the need for cleanliness when working on hy-
draulic system components. Contamination will cause
excessive wear of hydraulic components.
2. Put metal caps or plugs on any hydraulic lines left
open or exposed during testing or after removal of com-
ponents.
3. The engine must be in good operating condition. Use
a phototach (non−contact tachometer) when performing
a hydraulic test. Engine speed can affect the accuracy
of the test readings. Monitor engine RPM during hy-
draulic testing. Use the information below when per-
forming hydraulic system tests. If engine RPM is above
or below the specified speed during a test, you will need
to adjust the expected hydraulic performance paramet-
ers (aprox. 3% per 100 engine rpm at full throttle)
IMPORTANT: Hydraulic component output volume
relates directly to engine RPM. For every 100 engine
rpm the following component output volumes will
change by the volume listed.
Hydrostat: 100 engine RPM = 1.07 GPM or 137.4 oz.
(4.06 ltr) of hydraulic fluid displaced per minute
Internal Charge Pump: 100 engine RPM = 0.18 GPM
or 23.3 oz. (688 cc) of hydraulic fluid displaced per
minute
Gear Pump (P1): 100 engine RPM = 0.41 GPM or
52.6 oz. (1556 cc) of hydraulic fluid displaced per
minute
Gear Pump (P2): 100 engine RPM = 0.15 GPM or
118.8 oz. (557 cc) of hydraulic fluid displaced per
minute
NOTE: The hydraulic pumps are connected directly to
the engine crankshaft, so 1 engine RPM = 1 pump RPM.