JLG 450A_AJ Series II Service Manual - Manual (Page 40)

SECTION 2 - GENERAL
2-4 – JLG Lift – 3121180
2.3 LUBRICATION AND INFORMATION
Hydraulic System
1. Contamination is the primary enemy of a hydraulic
system. Contaminants enter the system by using
inadequate hydraulic oil, allowing moisture, grease,
filings, sealing components, sand, etc., to enter
when performing maintenance, or by allowing the
pump to cavitate due to insufficient system warm-
up, or leaks in the pump supply (suction) lines.
2. Design and manufacturing tolerances of component
working parts are very close. Even the smallest
amount of dirt or foreign matter entering a system
can cause wear or damage to components and ca
cause faulty operation. Take every precaution to
keep hydraulic oil clean, including reserve oil in stor-
age. Hydraulic system filters should be checked,
cleaned, and/or replaced as necessary, at intervals
specified in the Lubrication Chart in Section 1.
Always examine filters for evidence of metal parti-
cles.
3. Cloudy oils indicate a high moisture content which
permits organic growth, resulting in oxidation or cor-
rosion. If this condition occurs, the system must be
drained, flushed, and refilled with clean oil.
4. It is not advisable to mix oils of different brands or
types, as they may not contain the same required
additives or be of comparable viscosities. Good
grade mineral oils, with viscosities suited to ambient
temperatures in which the machine is operating, are
recommended for use.
NOTE: Metal particles may appear in oil or filters of new
machines due to wear-in of meshing components.
Hydraulic Oil
1. Refer to Section 1 for recommendations for viscosity
ranges.
2. JLG recommends Mobilfluid 424 hydraulic oil, which
has an SAE viscosity of 10W-30 and a viscosity
index of 152.
STARTUP OF HYDRAULIC SYSTEM WITH OIL TEMPERATURES
BELOW -15°F (-26°C) IS NOT RECOMMENDED.
3. If it is necessary to start the system in a sub-zero
environment, heat oil with a low density, 100VAC
heater to a minimum temperature of -15°F (-26°C).
SYSTEMS USING DTE 13 OIL SHOULD NOT BE OPERATED AT
TEMPERATURES ABOVE 200 DEGREES F (94 DEGREES C) UNDER
ANY CONDITION.
4. The only exception to the previous is to drain and fill
the system with Mobil DTE 13 oil or equivalent. This
allows start up at temperatures down to -20° F (-29°C).
However, use of this oil will give poor performance at
temperatures above 120°F (49° C).
Changing Hydraulic Oil
1. Use of any recommended crankcase or hydraulic
oils eliminates the need for changing oil on a regular
basis. However, filter elements must be changed
after the first 50 hours of operation and every 300
hours thereafter. If it is necessary to change the oil,
use only those oils meeting or exceeding specifica-
tions appearing in this manual. If unable to obtain
the same type of oil supplied with the machine, con-
sult local supplier for assistance in selecting the
proper equivalent. Avoid mixing petroleum and syn-
thetic base oils. JLG Industries recommends chang-
ing the hydraulic oil annually.
2. Use every precaution to keep hydraulic oil clean. If
oil must be poured from original container into
another, clean all possible contaminants from the
service container. Always clean filter mesh element
and replace cartridge any time system oil is
changed.
3. While unit is shut down, make a thorough inspection
of all hydraulic components, lines, fittings, etc., as
well as a functional check of each system, before
placing machine back in service.
Lubrication Specifications
Specified lubricants, as recommended by the component
manufacturers, are always the best choice. However,
multi-purpose greases usually have qualities which meet a
variety of single purpose grease requirements. Should
any question arise regarding use of greases in mainte-
nance stock, consult your local supplier for evaluation.
Refer to Section 1 for an explanation of the lubricant key
designations appearing in the Lubrication Chart.