Service. Operations required periodically to keep an item in proper operating condition, i.e., to clean (includes
decontaminate, when required), to preserve, to drain, to paint, or to replenish fuel, lubricants, chemical fluids, or gases.
Adjust. To maintain or regulate within prescribed limits, by bringing into proper or exact position, or by setting
the operating characteristics to specified parameters.
Aline. To adjust specified variable elements of an item to bring about optimum or desired performance.
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
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.
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 3d position code of the SMR code.
Repair. The application of maintenance services', including fault location/troubleshooting2, removal/installation,
and disassembly/assembly procedures3, 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.
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.
Rebuild. Consists of those services/actions necessary for the restoration of unserviceab le 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
measurements (hours/miles, etc.) considered in classifying Army equipment/components.
Services - inspect, test, service, adjust, aline, calibrate, and/or replace.
Fault 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 (UUT).
Disassemble/assemble - encompasses the step-by-step taking apart (or breakdown)