Diesel Technician Mechanic Job Duties: Determines vehicle condition by conducting inspections and diagnostic tests; identifying worn and damaged parts. Troubleshoots and diagnosis problems. Diesel Mechanic performs inspection, maintenance, repairs, and overhauls of diesel engines. Keeps equipment available for use by completing preventive maintenance schedules; installing component and part upgrades; controlling corrosion; completing winterization procedures. Replaces and/or refurbishes parts. While a diesel mechanic’s day-to-day duties and responsibilities are determined by where they work, there are many core tasks associated with the role. Diesel mechanics consult with customers, read work orders, and determine the work required before they begin making repairs. Requirements and Responsibilities. Based on our analysis of job listings, these include: Create Written Maintenance Records. Being a Diesel Mechanic utilizes computer electronics systems to interpret failure modes. Diesel Mechanic Job Description Diesel mechanics posses the know how to maintain, repair and service diesel engines, which are used to run a variety of vehicles, such as cars, buses, trucks, trains, ships and agricultural and construction equipment.