Manitowoc Grove GRT8120, Operator'S Manual

Page: 387 / 448

Grove
Published 3-22-2021, Control # 702-02
6-9
GRT8120 OPERATOR MANUAL MAINTENANCE AND LUBRICATION
6
CYLINDER ROD SURFACE PROTECTION
Steel cylinder rods include a thin layer of chrome plating on
their surfaces to protect them from corroding. However,
chrome plating inherently has cracks in its structure which
can allow moisture to corrode the underlying steel. At typical
ambient temperatures, hydraulic oil is too thick to penetrate
these cracks. Normal crane operating temperatures will
allow hydraulic oil to warm sufficiently to penetrate these
cracks and if cranes are operated daily, protect the rods.
Cranes that are stored, transported, or used in a corrosive
environment (high moisture, rain, snow, or coastline
conditions) need to have the exposed rods protected more
frequently by applying a protectant. Unless the crane is
operated daily, exposed rod surfaces will corrode. Some
cylinders will have rods exposed even when completely
retracted. Assume all cylinders have exposed rods, as
corrosion on the end of the rod can ruin the cylinder.
It is recommended that all exposed cylinder rods be
protected using Boeshield® T-9 Premium Metal Protectant.
Manitowoc Crane Care has Boeshield® T-9 Premium Metal
Protectant available in 12 oz. aerosol cans by ordering part
number 9999101803 through the Parts Department.
Cylinder operation and inclement weather will remove the
Boeshield® protectant; therefore, inspect crane once a week
and reapply Boeshield® to unprotected rods.
WIRE ROPE LUBRICATION
Wire rope is lubricated during manufacturing so that the
strands, and individual wires in strands, may move as the
rope moves and bends. A wire rope cannot be lubricated
sufficiently during manufacture to last its entire life.
Therefore, new lubricant must be added periodically
throughout the life of a rope to replace factory lubricant which
is used or lost. For more detailed information concerning the
lubrication and inspection of wire rope, refer to
Wire Rope in
Section 1 - Introduction of the Service Manual .
LUBRICATION POINTS
A regular frequency of lubrication must be established for all
lubrication points. Normally, this is based on component
operating time. The most efficient method of keeping track of
lube requirements is to maintain a job log indicating crane
usage. The log must use the engine hourmeter to ensure
coverage of lube points that will receive attention based on
their readings. Other lubrication requirements must be made
on a time basis, for example, weekly, monthly, etc.
Check all oil levels with crane parked on a level surface in
transport position, while oil is cold, unless otherwise
specified.
On plug type check points, oil levels are to be at the bottom
edge of the check port.
All grease fittings are SAE STANDARD unless otherwise
indicated. Grease non-sealed fittings until grease is seen
extruding from the fitting. One pump on a standard 0.45 kg
(1 lb) grease gun equals 28 grams (1 oz) of EP-MPG.
Over-lubrication on non-sealed fittings will not harm fittings
or components, but under-lubrication will definitely lead to a
shorter lifetime.
Unless otherwise indicated, items not equipped with grease
fittings, such as linkages, pins, levers, etc., should be
lubricated with oil once a week. Motor oil, applied sparingly,
will provide the necessary lubrication and help prevent the
formation of rust. An Anti-Seize compound may be used if
rust has not formed, otherwise the component must be
cleaned first.
Grease fittings that are worn and will not hold the grease
gun, or those that have a stuck check ball, must be replaced.
Where wear pads are used, cycle the components and
lubricate again to make sure that the entire wear area is fully
lubricated.