TCM FB-8 Series, Service Manual

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CAUTION
1. Inspections are carried out to locate the cause of troubles and to determine whether parts
are reusable or not. Inspections must be carried out only by personnel with a certain
amount of knowledge and experience in hydraulic equipment.
2. The “useful limit” shown in this section should be used as a rough guide. We do not always
guarantee the performance of a part if it does not reach its useful limit.
Name of component Items to be checked Remarks (cause and others)
①
Front cover (a) Check for cracks or damage. Oil pressure is too high.
CAUTION
The mating section between the front cover and the pump body looks black
in some parts. This is caused by the friction between aluminum parts and is
not a problem.
②
Pump body (cast
iron)
(a) Check for cracks or damage. Oil pressure is too high.
(b) Check wipe depth or wipe surface.
Oil pressure is too high.
Useful limit
Wipe depth limit: less than 0.04 mm [0.0016 in]
(c) Check for signs of interference with
gear at discharge side.
Runout of gears
Pump’s performance is not affected if
there is a sign of interference.
③
Drive and
driven gears
(a) Check shaft ends and keyways for
cracks, damage or undue wear.
They might occur when gears are runout
or insufficiently lubricated, or when oil
pressure is too high.
(b) Check journal (in the area
which slides on the bearing) for
discoloration, undue wear, or
roughness.
Contaminants in oil, too high oil
temperature (120°C [248°F] or higher),
too frequently idle operations
CAUTION
BUSHING
INPUT
SHAfT
OIL SEAL
BUSHING
SIDE PLATE
The shaft might have the following
scratches or scores on its outer
diameter:
(a) Those caused by a hard object
between the shaft and bushing.
(b) Those caused by the oil seal’s main
lip
(c) Those caused by the oil seal’s dust
lip
Useful limit
Roughness on journal (a): 0.8S - 1.6S
Roughness on oil seals (b and c): 1.6S - 3.2S
7. HYDRAULIC SYSTEM