Once the cause of the problem is found, mechanics make adjustments or repairs. During routine service, mechanics inspect and lubricate engines and other components. They also repair or replace parts before they cause breakdowns. Mechanics usually follow a checklist to ensure they examine important parts, such as belts, hoses, plugs, brake and fuel systems, and other potentially troublesome items. Automotive mechanics , often called automotive service technicians , inspect, maintain or repair automobiles and light trucks with gasoline engines, such as vans and pickups.
Diesel mechanics work on diesel-powered trucks, buses and heavy equipment.
Aviation mechanics adjust, align and calibrate aircraft systems. They examine and inspect engines or other components for cracks, leaks or breaks, and test engine and system operations to detect and diagnose malfunctions. They may also repair and rebuild aircraft structures, functional components and parts, such as wings and fuselage, rigging and hydraulic units. Although aviation mechanics require specialized training in aircraft engines and systems, a background in automotive mechanics is a good start for this career. In the most modern shops, service technicians use electronic service equipment, such as infrared engine analyzers and computerized diagnostic devices.