TM 9-4120-399-14
g. Remove / Install. To remove and install the same item when required to perform
service or other maintenance functions. Install may be the act of emplacing, seating, or fixing
into position a spare, repair part, or module (component or assembly) in a manner to allow the
proper functioning of an equipment or system.
h. Replace. To remove an unserviceable item and install a serviceable counterpart in its
place. "Replace" is authorized by the MAC and is shown as the 3rd position code of the SMR
code.
i. Repair. The application of maintenance services, including fault location/trouble-
shooting, removal/installation, and disassembly/assembly procedures, and maintenance actions to
identify troubles and restore serviceability to an item by correcting specific damage, fault,
malfunction, or failure in a part, subassembly, module (component or assembly), end item, or
system.
j. Overhaul. That maintenance effort (service/action) prescribed to restore an item to a
completely serviceable/operational condition as required by maintenance standards in appropriate
technical publications (i.e., DMWR). Overhaul is normally the highest degree of maintenance
performed by the Army. Overhaul does not normally return an item to like new condition.
k. Rebuild. Consists of
those service/sections necessary for the
restoration of
unserviceable
equipment to a like new condition in accordance with original manufacturing standards. Rebuild
is the highest degree of material maintenance applied to Army equipment. The rebuild operation
includes the act of returning to zero those age measurements (hours/miles, etc.) considered in
classifying Army equipment/components.
B-3. EXPLANATION OF COLUMNS IN THE MAC, SECTION II.
a. Column 1, Group Number. Column 1 lists functional group code numbers, the purpose
of which is to identify maintenance significant components, assemblies, subassemblies, and
modules with the next highest assembly. End item group number shall be "00."
b. Column 2, Component/Assembly. Column 2 contains the names of components,
assemblies, subassemblies, and modules for which maintenance is authorized.
c. Column 3, Maintenance Function. Column 3 lists the functions to be performed on the
item listed in Column 2. (For detailed explanation of these functions, see paragraph B-2.)
d. Column 4, Maintenance Category. Column 4 specifies, by the listing of a work time
figure in the appropriate subcolumn(s), the category of maintenance authorized to perform the
function listed in Column 3. This figure represents the active time required to perform that
maintenance function at the indicated category of maintenance. If the number or complexity of
the tasks within the listed maintenance function vary at different maintenance categories,
appropriate work time figures will be shown for each category. The work time figure represents
the average time required to restore an item (assembly, subassembly, component, module, end
item, or system) to a serviceable condition under typical field operating conditions. This time
includes preparation time (including any necessary disassembly/assembly time),
troubleshooting/fault location time, and quality assurance/quaility control time in addition to the
B-2