Parts manual for the Caterpillar 390D L excavator (WAP1 series and later) equipped with a C18 engine, written in English. The document contains a comprehensive listing of all machine components, organized by system: engine, lubrication, cooling, intake and exhaust, fuel, electrical system, power train, frame, undercarriage, hydraulic system, attachments, and operator station. It includes part numbers, descriptions, and quantities to facilitate spare part identification and ordering.