B-2.7 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.
B-2.8 Replace. To remove an unserviceable item and install a serviceable counterpart in its place. "Replace" is
authorized by the MAC and assigned maintenance level is shown as the third position code of the Source,
Maintenance and Recoverability (SMR) code.
B-2.9 Repair. The application of maintenance services1, including fault location/troubleshooting2,
removal/installation, and disassembly/assembly3 procedures, and maintenance actions4 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.
B-2.10 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 publication.
Overhaul is normally the highest degree of maintenance performed by the Army. Overhaul does not normally return
an item to like new condition.
B-2.11 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 materiel
maintenance applied to Army equipment. The rebuild operation includes the act of returning to zero those age
measurement (e.g., hour/miles) considered in classifying Army equipment/components.
EXPLANATION OF COLUMNS IN THE MAC, SECTION II.
B-3.1 Column (1), Functional Group Number. Column (1) lists Functional Group Code (FGC) numbers, the
purpose of which is to identify maintenance significant components, assemblies, subassemblies, and modules with
the Next Higher Assembly (NHA).
B-3.2 Column (2), Component/Assembly. Column (2) contains the item names of components, assemblies,
subassemblies, and modules for which maintenance is authorized.
B-3.3 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, refer to Maintenance Functions outlined in paragraph B-2.)
B-3.4 Column (4), Maintenance Level. Column (4) specifies each level of maintenance authorized to perform
each function listed in column (3), by indicating work time required (expressed as man-hours in whole hours or
decimals) in the appropriate sub column. This work time figure represents the active time required to perform that
maintenance function at the indicated level of maintenance. If the number or complexity of the tasks within the listed
maintenance function varies at different maintenance levels, appropriate work time figures will be shown for each
level. 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/quality control time in addition to the time required to perform the specific tasks identified
1Services - inspect, test, service, adjust, align, calibrate, and/or replace.
2Fault location/troubleshooting- The process of investigating and detecting the cause of equipment malfunctioning; the act of isolating
a fault within a system or Unit Under Test (UUT).
3Disassembly/assembly - The step-by-step breakdown (taking apart) of a spare/functional group coded item to the level of its least
component (i.e., assigned an SMR code) for the level of maintenance under consideration (i.e., identified as maintenance significant).
4Actions - Welding, grinding, riveting, straightening, facing, machining, and/or resurfacing.