JLG G6-42A Service Manual - Manual (Page 68)

Boom
3-30 G6-42A, G9-43A, G10-43A
3.12.3 Chain Lubrication
After inspection and before being returned to service,
chains must be lubricated with Mystik Tetrimoly Grease.
The lubricant must penetrate the chain joint to prevent
wear. Applying lubricant to the external surfaces will
prevent rust, but the chains should be articulated to
make sure the lubricant penetrates to the working
surfaces between the pins and links.
To prepare the chain for lubrication, the chain plates
should be brushed with a stiff brush or wire brush to
clear the space between the plates so that lubricant can
penetrate to the working surfaces.
Lubricant may be applied with a narrow paint brush or
directly poured on, but the chain should be well flooded
with lubricant and the boom should be extended and
retracted to be sure that the lubricant penetrates to the
working surfaces. All surplus lubricant should be wiped
away from the external surfaces. DO NOT use a solvent
for this wiping operation.
Regular application of lubricant is necessary to make
sure that all working surfaces are adequately lubricated.
In extremely dusty conditions, it may be necessary to
lubricate the chains more often.
Lubrication of chains on vehicles working consistently in
extreme hot or cold conditions requires special
consideration. It is important that a reputable lubrication
specialist, a JLG Distributor or the vehicle distributor be
consulted for guidance.
3.13 FORKS
Forks should be cleaned and inspected prior to being
attached to carriage. If the following criteria is not met,
forks must be removed from service immediately.
Daily Inspection
1. Inspect forks (1) for cracks, paying special attention
to heel (2) and mounting tubes (3).
2. Inspect forks for broken or bent tips (4) and twisted
blades (5) and shanks (6).
Yearly Inspection
1. Straightness of the upper face of blade (5) and the
front face of shank (6) should not exceed 0.5 percent
of the length of blade or height of shank.
2. Angle (7) between upper face of blade and front face
of shank should not exceed 93 degrees.
3. Thickness of blade (8) and shank (9) should not be
reduced to 90 percent of original thickness.
Note: Contact the local Caterpillar dealer with the fork
part number to find the manufactured dimensions of the
fork blade.
4. Ensure fork length (10) is adequate for intended
loads.
5. Fork markings should be legible, re-stamp if
required.
6. Compare fork tips (11) when mounted on a carriage.
Maximum difference in height of fork tips is 3 percent
of the length of the blade (10).
MH6460
3
2
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9
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10
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