TM 5-3810-300-24 & P3
General Information
GENERAL PROCEDURES
Various factors such as the type of operation of the engine,
In many cases, a serviceman is justified in replacing parts with
hours in service and next overhaul period must be considered
new material rather than attempting repair. However, there
when determining whether new parts are installed or used
are times where a slight amount of reworking or reconditioning
parts are reconditioned to provide trouble-free operation.
may save considerable added expense. Crankshafts, cylinder
liners and other parts are in this category. For example, if a
For convenience and logical order in disassembly and
cylinder liner is only slightly worn and within usable limits, a
assembly, the various sub-assemblies and other related parts
honing operation to remove the glaze may make it suitable for
mounted on the cylinder block will be treated as separate
reuse, thereby saving the expense of a new part. Exchange
items in the various sections of the manual.
assemblies such as injectors, fuel pumps, water pumps and
blowers are also desirable service items.
DISASSEMBLY
is not always necessary to mount the engine on an overhaul
Before any major disassembly, the engine must be drained of
stand.
lubricating oil, water and fuel. Lubricating oil should also be
drained from any transmission attached to the engine.
Parts removed from an individual engine should be kept
together so they will be available for inspection and assembly.
To perform a major overhaul or other extensive repairs, the
Those items having machined faces, which might be easily
complete engine assembly, after removal from the vehicle and
damaged by steel or concrete, should be stored on suitable
transmission, should be mounted on an engine overhaul
wooden racks or blocks, or a parts dolly.
stand; then the various subassemblies should be removed
from the engine. When only a few items need replacement, it
CLEANING
Before removing any of the sub-assemblies from the engine
Solvent Tank Cleaning
(but after removal of the electrical equipment), the exterior of
the engine should be thoroughly cleaned. Then, after each
A tank of sufficient size to accommodate the largest part that
sub-assembly is removed and disassembled, the individual
will require cleaning (usually the cylinder block) should be
parts should be cleaned. Thorough cleaning of each part is
provided and provisions made for heating the cleaning solution
absolutely necessary before it can be satisfactorily inspected.
to 180-200 F (82-90 C).
Various items of equipment needed for general cleaning are
listed below.
Fill the tank with a commercial heavy-duty solvent which is
heated to the above temperature. Lower large parts directly
The cleaning procedure used for all ordinary cast iron parts is
into the tank with a hoist. Place small parts in a wire mesh
outlined under Clean Cylinder Block in Section 1.1; any special
basket and lower them into the tank. Immerse the parts long
cleaning procedures will be mentioned in the text wherever
enough to loosen .all of the grease and dirt.
required.
Rinsing Bath
Steam Cleaning
Provide another tank of similar size containing hot water for
rinsing the parts.
A steam cleaner is a necessary item in a large shop and is
most useful for removing heavy accumulations of grease and
Drying
dirt from the exterior of the engine and its sub-assemblies.
Parts may be dried with compressed air. The heat from the
hot tanks will quite frequently complete the drying of the parts
without the use of compressed air.
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