What is understood by engine ‘overhaul’ ?
In short, a complete overhaul means that all wear parts in the engine are renewed. All moving parts in an internal combustion engine are more or less susceptible to wear. Tolerances are restored to factory values during overhaul. This also happens with the ignition, the carburetor, the starter motor or dynastarter, or these components are completely renewed. If certain parts of the engine are not overhauled because they are not yet in need of overhaul, we speak of a partial overhaul or repair. The term restoration means that the engine is restored to its original state. This does not have to be the case for overhaul or repair.
The term overhaul is often misused. Overhaul is much more than just replacing a few parts or applying a new coat of paint. Engine overhaul is not cheap; new parts are produced in relatively small series, and overhaul is labor-intensive. Specific knowledge and experience are needed to be able to professionally overhaul magnet ignitions, carburetors and water pumps, for example. The definitions of overhaul for specific engine components are further explained on this website.
When you bring your engine for overhaul, the engine is first stripped of dirt, rust and old paint layers. This is done by sandblasting or chemical varnishing. Vulnerable appendages on the engine such as the ignition, carburetor, and starter are removed for this operation. After that the engine is completely disassembled, up to the smallest part. All parts are cleaned separately and visually inspected, and where possible measured for damage and wear. This measurement is done with proper measuring tools that have an accuracy up to 1/100 mm.