This comprehensive service and repair manual covers Renault vehicles equipped with the 852 J8S indirect injection, 4-cylinder diesel engine. Models include the Renault 18, Fuego, 20, 21, 25, 30, Safrane, Espace, Trafic, Master, and Jeep. This manual provides detailed instructions and exploded diagrams, mirroring the resources used by professional mechanics to ensure efficient and correct servicing and repair. It is designed to empower owners and technicians alike to maintain their vehicles in optimal condition, preserving their investment and performance. The scope of this manual is extensive, encompassing all essential aspects of engine maintenance and repair. It details engine identification, lubrication circuits, specifications, and required tooling. In-depth procedures for overhauling the engine, including cylinder head and block work, piston and con rod assembly, and accessory belt installation, are thoroughly explained. This manual serves as an indispensable resource for anyone needing to perform maintenance, diagnostics, or repairs on the specified Renault diesel engines, offering clear guidance for a wide range of tasks.