Safety Information - JLG sky trak mmv Service Manual

Hydraulic System
9.2

SAFETY INFORMATION

WARNING:
vehicle without following all safety precautions
as outlined in the "Safety Practices" section of
this manual. Failure to follow the safety prac-
tices may result in death or serious injury.
WARNING:
to cool before servicing any hydraulic compo-
nent. Hot hydraulic fluid can cause severe
burns.
Petroleum-based hydraulic fluids are used in this vehicle.
The temperature of hydraulic fluid increases during the
operation of various hydraulic functions. A heated petro-
leum-based hydraulic fluid presents a fire hazard, espe-
cially when an ignition source is present. Hydraulic fluid
has a flash point that ranges from 300-600° F (150-318° C)
and an auto-ignition temperature of 500-750° F (262-402° C).
Accordingly, periodically inspect all hydraulic system
components, hoses, tubes, lines, fittings, etc. Carefully
examine any deterioration and determine whether any
further use of the component would constitute a hazard.
If in doubt, replace the component.
WARNING:
sure before servicing any hydraulic compo-
nent. Escaping hydraulic fluid under pressure
can penetrate the skin causing death or seri-
ous injury.
Note: Residual pressure may remain in hydraulic cylin-
ders, hoses, valve bodies, components, etc. If the
hydraulic lines going to or coming from a component are
taut, slowly and cautiously relieve ("bleed off") pressure.
9.4
DO NOT service the
Wait for hydraulic fluid
Relieve hydraulic pres-
To relieve hydraulic pressure:
Whenever you disconnect a hydraulic line, coupler, fit-
ting, or other component, slowly and cautiously loosen
the part involved. A hissing sound or slow seepage of hy-
draulic fluid may occur in most cases. After the hissing
sound has ceased, continue removing the part. Any es-
caping oil should be directed into an appropriate contain-
er. Cap or otherwise block off the part to prevent further
fluid seepage.
WARNING:
engine, verify that all hydraulic connections are
properly tightened. Escaping hydraulic fluid
under pressure can penetrate the skin causing
death or serious injury.
Hydraulic system maintenance will, at times, require that
the engine be operated. Always follow safety precautions.
A major cause of hydraulic component failure is contam-
ination. Keeping the hydraulic fluid as clean as possible
will help avoid downtime and repairs. Sand, grit and other
contaminants can damage the finely machined surfaces
within hydraulic components. If operating in an exception-
ally dirty environment, change filters and inspect the fluid
more often. When servicing the system, cap or plug hy-
draulic fittings, hoses and tube assemblies. Plug all cylin-
der ports, valves, and the hydraulic reservoir and pump
openings until installation occurs. Protect threads from
contamination and damage.
Hydraulic functions are actuated by interfacing with elec-
trical system components (switches, solenoids and sen-
sors). When the hydraulic system is not functioning
properly, check the electrical aspect of the malfunctioning
circuit also. Refer to Section 10.7, Electrical System
Troubleshooting in this manual.
Before starting the
Model MMV Rev. 12/04