Keep original set identity separate
Retain the generator-set manufacturer, model and serial in the main equipment record. Add the installed engine’s own manufacturer, model and serial in the engine fields. Explain which identifiers relate to the assembled set and which to the current engine. Do not overwrite the set identity with the replacement engine’s plate data.
Document the replacement event
Gather the work order, invoice and any commissioning or test records that you possess. Record the replacement date, provider and description used in those documents. Keep terms such as new, rebuilt or remanufactured attributed to the supporting record; do not treat them as interchangeable or invent a scope from an invoice total.
Explain the hour readings
State what the current display shows and what the records establish about hours before and after replacement. If a controller or meter changed too, disclose that separately. Avoid subtracting an estimated earlier reading to create a precise-looking engine-hour total. A clear gap is better than arithmetic built on uncertain inputs.
Describe the rest of the package
Include known condition and service history for the alternator, controls, enclosure and other included equipment. Engine work does not document the condition of every other component. Give buyers the replacement evidence alongside the complete set history so they can evaluate the actual assembly and any remaining inspection needs.