Diesel Engine Mechanic  What They Do

Just the Facts


Bus and Truck Mechanics and Diesel Engine Specialists Career Video



Diagnoses, adjusts, repairs, or overhauls buses and trucks, or maintains and repairs any type of diesel engines. Includes mechanics working primarily with automobile or marine diesel engines.

This career is part of the Transportation, Distribution and Logistics cluster Facility and Mobile Equipment Maintenance pathway.


A person in this career:

  • Inspects brake systems, steering mechanisms, wheel bearings, and other important parts to ensure that they are in proper operating condition.
  • Uses handtools such as screwdrivers, pliers, wrenches, pressure gauges, and precision instruments, as well as power tools such as pneumatic wrenches, lathes, welding equipment, and jacks and hoists.
  • Adjusts and relines brakes, aligns wheels, tightens bolts and screws, and reassembles equipment.
  • Examines and adjusts protective guards, loose bolts, and specified safety devices.
  • Performs routine maintenance such as changing oil, checking batteries, and lubricating equipment and machinery.
  • Test drives trucks and buses to diagnose malfunctions or to ensure that they are working properly.
  • Raises trucks, buses, and heavy parts or equipment using hydraulic jacks or hoists.
  • Attaches test instruments to equipment, and reads dials and gauges to diagnose malfunctions.
  • Rebuilds gas or diesel engines.
  • Inspects and verifies dimensions and clearances of parts to ensure conformance to factory specifications.

Working Conditions and Physical Demands

People who do this job report that:

  • You would often handle loads up to 20 lbs., sometimes up to 50 lbs. You might do a lot of lifting, carrying, pushing or pulling.
  • Work in this occupation involves bending or twisting your body more than one-third of the time
  • Work in this occupation involves use of protective items such as safety shoes, glasses, gloves, hearing protection, a hard hat, or personal flotation devices
  • Exposure to pollutants, gases, dust, fumes, odors, poor ventilation, etc.
  • Requires getting into awkward positions
  • Lighting is either extremely bright or inadequate
  • Conditions are very hot (above 90 F) or very cold (under 32 F)
  • Work in this occupation involves using your hands to hold, control, and feel objects more than one-third of the time
  • Exposed to conditions such as high voltage electricity, combustibles, explosives, and chemicals more than once a month
  • Exposed to hazardous equipment such as saws, machinery, or vehicular traffic more than once a month
  • Sound and noise levels are loud and distracting
  • Work in this occupation requires being outside most of the time
  • Work in this occupation involves making repetitive motions more than one-third of the time
  • Work in this occupation involves standing more than one-third of the time
  • Work in this occupation involves walking or running more than one-third of the time

Working in this career involves (physical activities):

  • Picking out a particular sound in the presence of other sounds
  • Identifying color and seeing differences in color, including shades and brightness
  • Judging how far away an object is, or which of several objects is closer or farther away
  • Bending, stretching, twisting, or reaching
  • Detecting sounds and hearing the differences between sounds of different pitch and loudness
  • Seeing clearly up close
  • Identifying and understanding the speech of another person
  • Lifting, pushing, pulling, or carrying objects
  • Using abdominal and lower back muscles repeatedly or over time without tiring

Work Hours and Travel

  • Regular working hours and limited travel

Specialty and Similar Careers

Careers that are more detailed or close to this career:

  • Bus Mechanic --
  • Diesel Mechanic -- Repairs and maintains diesel engines used to power machines, such as buses, ships, trucks, railroad trains, electric generators, and construction machinery.
  • Diesel Technician --
  • Fleet Mechanic --
  • General Repair Mechanic --
  • Mechanic --
  • Service Technician --
  • Trailer Mechanic --
  • Transit Mechanic --
  • Truck Mechanic --