Überholung

Überholung is a German term used in engineering and maintenance to denote a thorough inspection, repair, and refurbishment of machinery or equipment with the aim of restoring it to a near-original or specified service condition. In practice, an Überholung goes beyond routine maintenance and may involve disassembly, measurement of tolerances, replacement of worn or damaged parts, cleaning, reassembly, alignment, and functional testing. The scope can vary from a partial overhaul of a subsystem to a full Generalüberholung of the entire machine.

The word stems from überholen, meaning “to overhaul,” from über- (over) and holen (to fetch). In usage, the noun Überholung is often qualified with terms such as Generalüberholung or Teilüberholung to indicate the extent of refurbishment.

Applications of Überholung are common in automotive maintenance (cars, trucks), rail vehicles, aircraft engines, ships, and industrial equipment such as turbines, pumps, or production lines. It is often defined in service contracts and maintenance planning to specify repair and refresh cycles; the duration and cost depend on the complexity, age of the equipment, and the availability of spare parts.

Typical process steps include inspection and teardown, assessment of wear, replacement or refurbishment of components, cleaning, reassembly, calibration, and testing, followed by documentation and certification. In some cases, preventive upgrades or modernization measures may be included as part of the overhaul.

Relation to maintenance concepts: Überholung is distinguished from routine Wartung (maintenance) and from Instandsetzung (repair of a fault) by its comprehensive scope and aim to restore operational reliability. In safety-critical industries (such as aviation, shipping, and rail), Generalüberholung is often performed by approved facilities under regulatory and quality controls, with traceability of parts, procedures, and compliance.