This manual covers the Volvo B17, B19, B21, and B23 engine series, known for their robust "Redblock" inline-4 cylinder configuration. These engines, available in displacements ranging from 1.7 to 2.3 liters, are recognized for their engineering quality and reliability. This service and repair manual provides comprehensive information for maintaining and servicing these versatile powerplants, which utilize fuel injection systems. The purpose of this manual is to serve as a definitive guide for owners, mechanics, and technicians. It details general maintenance procedures, troubleshooting techniques, and in-depth engine service and repair instructions. Coverage extends to periodic lubrication, transmission service, brake systems, electrical systems including wiring diagrams, suspension, steering, cooling systems, fuel injection, emission control, engine management, chassis and body, restraint systems, and axles.