NMC-WOLLARD MB-4 200-DF, Operation, Maintenance And Parts Manual

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Use low-pressure compressed air to remove
debris and dirt as necessary.
3.12.3.3 Frame, Engine, and Transmission
IMPORTANT: Be sure all openings are
closed or covered adequately before clean-
ing to prevent the entry of water into internal
parts.
Structural parts are best cleaned using soap
and water and suitable brushes. Steam
cleaning may also be done before disassem-
bly to remove heavy accumulations of
grease, oil, and dirt from exterior of engine,
transmission and rear axle assembly.
3.12.3.4 Metal Parts
IMPORTANT : Reassemble and oil metal
parts as soon as possible after cleaning. Do
not operate parts unless a film of lubricating
oil is applied.
Wash metal parts in cleaning solvent. Allow
to air dry. Do not use compressed air to dry
parts. The moisture generally present in air
systems may cause corrosion. Lubricate
metal parts as soon as possible after clean-
ing.
3.12.3.5 Gears
Clean gears using a soft bristle brush and
cleaning solvent. Remove foreign matter
from the gears.
3.12.4 Inspecting Parts
Inspect all parts visually for cracks, breaks,
scratches, dents, bends, punctures, galling,
wear, scoring, stripped threads, distortion
and deformation. Give special attention to
bearing surfaces, mating surfaces, gaskets
and seals. Specific dimensional checks and
tests are given where required.
3.12.5 Repair and Replacement
3.12.5.1 Structural Parts
Structural parts, enclosing, and supporting
members may be repaired by welding,
brazing and refinishing. Major repairs
should be performed by overhaul facilities.
Where repainting is required, the surface
should first be suitably prepared and
primed.
3.12.5.2 Wiring
Wiring should be repaired in accordance
with standard automotive practices.
3.12.5.3 Gaskets and Seals
Gaskets, oil seals, preformed packing, and
seals should be replaced instead of being
cleaned and reused, unless otherwise
specified by local directives. Replace any
seals and packings that show any deterio-
ration or damage.
NOTE: Use repair kits when available.
3.12.6 Reassembly and Installation
Unless otherwise specified, reassembly
and installation are the reverse of removal
and disassembly. Use the illustrations in
Section 10 as a reference.
PREVENTIVE MAINTENANCE PAGE 3-15
JULY 31, 2007
M200 MB4 Tow Tractor Manual No. 42975