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Navy NEC · Engineering

739B SSN/SSBN Diesel Engine (Fairbanks-Morse) Maintenance Technician

Current service use not established

This code is listed in the directory. Inclusion alone does not confirm current service use.

A Navy Enlisted Classification: a skill designation sailors hold in addition to their rating.

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Overview

An SSN and SSBN Diesel Engine Maintenance Technician performs preventive, organizational, and intermediate maintenance on Fairbanks Morse submarine diesel engines and their components. This technician takes readings, makes adjustments for proper engine operation and repair, and performs shipboard lubrication oil, trend, and water analysis duties.

Core Skills

  • Lube oil, water, and trend analysis
  • Governor, injector, and fuel system maintenance
  • Starting and scavenging air system maintenance

Civilian Career Paths

Career associations are editorial assessments of the cited evidence, not an official crosswalk unless the evidence explicitly says so. O*NET supplies civilian occupation information, not proof of a military match. Related experience does not confer civilian qualifications. Tasks and tools below describe civilian work, not military training.

Diesel Engine Specialist

Submarine diesel component maintenance and adjustments based on operating readings transfer directly to civilian diesel engine servicing and diagnosis.

How to prepare: Complete hands-on training in civilian diesel diagnostics using software such as Cummins INSITE. Broader bus and truck roles also cover brake and steering systems not documented in these military duties.

What the civilian work involves
  • Use handtools, such as screwdrivers, pliers, wrenches, pressure gauges, or precision instruments, as well as power tools, such as pneumatic wrenches, lathes, welding equipment, or jacks and hoists.
  • Attach test instruments to equipment, and read dials and gauges to diagnose malfunctions.
Civilian tools and software (examples)
  • Cummins INSITE

Machinery Maintenance Worker

Maintenance of pumps, blowers, bearings, and lubrication systems provides relevant experience for servicing and replacing industrial machinery components.

How to prepare: Complete a hands-on machinery maintenance course focused on disassembly, reassembly, and component replacement.

What the civilian work involves
  • Dismantle machines and remove parts for repair, using hand tools, chain falls, jacks, cranes, or hoists.
  • Reassemble machines after the completion of repair or maintenance work.
  • Install, replace, or change machine parts and attachments, according to production specifications.
Civilian tools and software (examples)
  • Computerized maintenance management system software CMMS

Notes & Sources

Evidence for this guidance (3 documents)
  1. NAVPERS 18068F Vol II (NEOCS, Jul 2026 edition): NEC 739B

    [1] NEC entry "739B - SSN/SSBN Diesel Engine (Fairbanks-Morse) Maintenance Technician"; cached text line 17551; NAVPERS 18068F Vol II, 2026-07 edition

    Supports: Lube oil, water, and trend analysis, Governor, injector, and fuel system maintenance, Starting and scavenging air system maintenance, Diesel Engine Specialist (O*NET 49-3031.00), Machinery Maintenance Worker (O*NET 49-9043.00)

  2. O*NET: Bus and Truck Mechanics and Diesel Engine Specialists

    [2] O*NET 30.3 occupational data

    Supports: Diesel Engine Specialist (O*NET 49-3031.00)

  3. O*NET: Maintenance Workers, Machinery

    [3] O*NET 30.3 occupational data

    Supports: Machinery Maintenance Worker (O*NET 49-9043.00)

Defense contractor jobs for 739B

Descriptions may be summarized for clarity. Verify all information with your branch career counselor or official military documentation before making career decisions.

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