B-2.8. Replace. To remove an unserviceable item and installl a serviceable counterpart in its place.
Replace is authorized by the MAC and is shown as the 3d position code of the SMR code.
B-2.9. Repair. The application of maintenance servicesl, 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 (i.e., DMWR). 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 (hour/miles, etc.) considered in classifying Army
B-3. EXPLANATION of COLUMNS in the MAC, SECTION II
B-3.1. 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
higher assembly. End item group number shall be 00.
B-3.2. Column 2, Component/Assembly. Column 2 contains the names of components, assemblies,
subassemblies, and modules for which maintenance is authorized.
B-3.3. Column 9, 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.)
B-3.4. Column 4, Maintenance Level. Column 4 specifies, by the listing of a work time figure in the
appropriate subcolumn(s), the level 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 level
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/quality control time in addition to the time
required to perform the specific tasks identified for the maintenance functions authorized in the
maintenance allocation chart. The symbol designations for the various maintenance categories are as
¹Services - inspect, test, service, djust, aline, calibrate, and/or replace.
²Fault locate/troubleshoot - The process of investigating and detecting the cause of equipment malfunctioning; the act of
isolating a fault within a system or unit under test (UW).
³Disassemble/ assemble - encompasses the step-by-step taking apart (or breakdown) of a spare/functional group coded item
to the level of its least componency identified as maintenance significant (i.e., assigned an SMR code) for the level of maintenance
4Actions - welding, grinding, riveting, straightening, facing remachinery, and/or resurfacing.