AxleTech TA277, Service Manual

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General Assembly Instructions
vii
General Assembly Instructions
Tapered Roller Bearings
!
CAUTION
Dry bearings with clean paper or rags. NEVER use
compressed air, which can cause abrasive particles to
contaminate the bearings. Damage to components and
reduced lining life can result.
If parts are clean and properly lubricated, it is rare for
bearings to be damaged. Proper installation is also criti-
cal to avoid vibration, noise, and reduced bearing life.
Bearings should be removed when:
• Bearing surfaces show abnormal wear
• Bearings are chipped (due to improper cleaning
during assembly, improper lubrication, or a broken
component inside the transfer case)
• Centers of the large diameter end of the rollers are
worn level with or below the surface
• Centers of the large diameter end of the rollers are
worn to a sharp edge
• A roller groove is worn in the cup or cone inner race
surfaces visible at the small or large diameter ends of
both parts
• Deep cracks or breaks are present in the cup, cone
inner race, or roller surfaces
• Bright wear marks are present on the outer surface of
the roller cage
• Etching and pitting is present on the rollers and on
surfaces of the cup and cone inner race that touches
the rollers
• Spalling or fl aking is present on the cup and cone
inner race surfaces that touch the rollers
During disassembly:
• Remove bearings with pullers designed for this
purpose to avoid damaging the bearing.
• Carefully wash and re-lubricate all bearings as
removed and protectively wrap until ready for use.
• Store all bearings in a dry and clean area to minimize
the possibility of corrosion, contamination, or other
damage.
During assembly:
• Install bearings in a clean environment, free from
dust, debris, moisture, and other contaminants.
• Machining, fi ling, soldering, grinding, etc. should
be kept away from the assembly area to prevent
contaminating the bearings.
• Check the cleanliness of the bearing:
• If the bearing is new, unpack it immediately
before assembly.
• Used bearings should be cleaned with petrol or
benzine and then oiled.
• Verify the bore is deburred and cleaned before
installing the bearing. Use 180-grit emery cloth to
remove small imperfections in the metal.
• Bearings are installed the easiest by cooling or
heating (in hot oil to 80°C) instead of using a press.
Do not apply any shock or impact techniques (like
hammering) to install the bearings.
• When a bearing has been heated for assembly, apply
a small amount of grease or oil after assembly.
• When installing on a tight shaft, force is to be applied
to the inner ring only.
Castings
• Inspect for damage or cracking. Replace as required.
NEVER weld to repair the casting.
Gears
• Inspect for pitting or damage. Replace as required.
• Replace beveled gear set, as required, with a matched
set.
Seals
!
WARNING
When applying some silicone gasket materials, small
amounts of acid vapor are present. To prevent possible
serious injury, the work area must be well-ventilated.
If the silicone gasket material gets into your eyes,
fl ush them with water for 15 minutes. Have your eyes
checked by a doctor as soon as possible.
• O-rings: After removal, always replace with new ones.