The CM Rating

The original Mechanic rating evolved in 1948 from the SeaBee ratings of Machinist's Mate (Equipment Operators) and the Motor Machinist's Mate. The Mechanic rating finally changed its name to Construction Mechanic in 1958.

The Navy's computerized personnel system associates the rating name with an alphanumeric Navy Occupational Specialty (NOS) code. For CM, the NOS is H120.

Construction Mechanics repair and maintain heavy construction and automotive equipment including, buses, dump trucks, bulldozers, rollers, cranes, backhoes, pile drivers, and tactical vehicles. CMs also prepare detailed maintenance records and cost control data and acquire parts.

Construction Mechanic class "A" school is approximately 16 weeks long, and the school is located in Port Hueneme, California. The CM rating requires a minimum 5 year enlistment obligation.

Construction Mechanic (NOS H120)

The duties performed by CMs include diagnosing and troubleshooting equipment failures and repairing and maintaining diesel and gasoline engines. They adjust and repair ignition, fuel, electrical, hydraulic and steering systems, as well as, maintain and repair chassis, frames and bodies.

CMs work with hoisting and jacking equipment, power tools, measuring instruments, gauges and meters, and lubricating equipment. They maintain and repair tires, batteries, brake systems, and valves. Perform shop management functions such as maintenance scheduling and spare parts inventory control. They make estimates of material, labor, and equipment requirements.

Career Sea - Shore Rotation Chart

Construction Mechanic Rating's Sea (SEA) Shore (SH) Rotation (months)

Sea tours and shore tours for Sailors that have completed four sea tours will be 36 months at sea followed by 36 ashore until retirement.

Qualifications, Interests, and Working Environment

Prospective CMs should be able to use various tools, equipment and machines. They should possess manual dexterity and be able to keep records, do detailed work and perform repetitive tasks. Other important qualities are resourcefulness, curiosity, good memory, and an interest in ideas and information.

Normal color perception is not required. Members of this rate are not required to be citizens of the United States.

Just as important are strong arithmetic, speaking and writing skills; good physical condition; and a cooperative attitude. Many construction mechanics perform in an automotive garage environment, while some work in the field to maintain equipment. People in this rating usually work closely with others under close supervision and perform both physical and mental tasks. Their many different duties may be performed in climates ranging from tropical to arctic. CM ASVAB Test requirement.

Opportunities to enter the CM rating are excellent for qualified applicants. About 1,450 men and women work as Construction Mechanics in the Navy.

Personnel in the Construction Mechanic rating are paid allowances (BAH, BAS, etc. if eligible) and enlisted basic military pay based on years of service and paygrade.

Credit Recommendations

The American Council on Education recommends the following semester hour credits in the associate and vocational degree programs, 3 semester hours for both automotive electrical systems and hydraulic brake service. An AA in Electrical/Mechanical Technology and an AAS in Mechanics and Maintenance with specialty in Mechanics can be earned from Coastline Community College and Thomas Edison State College, respectively.

Date Page Modified: October 25, 2018.