MAINTENANCE FUNCTIONS - Continued
c. Service. Operations required periodically to keep an item in proper operating condition, i.e., to
clean (decontaminate), to preserve, to drain, to paint, or to replenish fuel, lubricants, chemical,
d. Adjust. To maintain, within prescribed limits, by bringing into proper or exact position, or by
setting the operating characteristics to specified parameters.
e. Align. To adjust specified variable elements of an item to bring about optimum or desired
f. Calibrate. To determine and cause corrections to be made or to be adjusted on instruments or
test, measuring and diagnostic equipments used in precision measurement. Consists of
comparisons of two instruments, one of which is a certified standard of known accuracy, to
detect and adjust any discrepancy in the accuracy of the instrument being compared.
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.
i. Repair. The application of maintenance services (inspect, test, service, adjust, align, calibrate,
replace) or other maintenance actions (welding, grinding, riveting, straightening, facing,
remachining, or resurfacing) to restore serviceability to an item by correcting specific damage,
fault, malfunction, or failure in a part, subassembly, module (component or assembly) end item,
j. Overhaul. That maintenance effort (service/action) necessary to restore an item to a
completely serviceable/operational condition as prescribed by maintenance standards (i.e.,
DMWR) in appropriate technical publications. Overhaul is normally the highest degree of
maintenance performed by the Army. Overhaul does not normally return an item to like new
k. Rebuild. Consists
of those services/actions necessary for the restoration
equipment to a like new condition in accordance with the 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.
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 components, assemblies, subassemblies, and modules within the next
b. Column (2) - Component/Assembly. Column 2 contains the names of components,
assemblies, subassemblies, and modules for which maintenance is authorized.