g. Install. The act of emplacing, seating, or fixing into position an item, part, or module (component or
assembly) in a manner to allow the proper functioning of an equipment or system.
h. Replace. The act of substituting a serviceable like type part, subassembly, or module (component or
assembly) for an unserviceable counterpart.
i. Repair. The application of maintenance services1 or other maintenance actions2 to restore
serviceability to an item by correcting specific damage, fault, malfunction, or failure in a part, subassembly,
module (component or assembly), and items, or system.
j. Overhaul. The maintenance effort (services/actions) necessary to restore an item to a completely
serviceable/operational condition as prescribed by maintenance standards (i.e., DMWR) in appropriate
technical publication. 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 services/actions 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 equipments/components.
B-3. Column Entries Used in the MAC.
a. Column 1, Group Number. Column 1 list group numbers, the purpose of which is to identify
components, assemblies, subassemblies, and modules with the next higher assembly.
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 Functions. Column 3 lists the functions to be performed on the item listed in
column 2. (For detailed explanation of these functions, see para. B-2).
d. Column 4, Maintenance Category.
(1) Column 4 specifies, by the listing of a "work time" figure in the appropriate sub-column(s), the lowest
1Services - inspect, test, service, adjust, align, calibrate, or replace.
2Action - welding, grinding, riveting, straightening, facing, remachining, or resurfacing.