This service repair shop manual covers the Yanmar Industrial Diesel Engine TNE Series, specifically models 2TNE68, 3TNE68, 3TNE74, and 3TNE78A. Designed for service, repair, and maintenance, these engines are engineered for industrial applications. This manual provides comprehensive guidance to ensure the continued optimal performance and longevity of your Yanmar industrial diesel engine. The purpose of this manual is to offer detailed, step-by-step instructions for all servicing and repairs, including routine maintenance. It features clear explanations, accompanying pictures, and wiring diagrams to facilitate a thorough understanding of all parts and repair procedures. This resource empowers owners and technicians to perform maintenance and repairs effectively, leading to significant savings on repair costs and ensuring the equipment remains in excellent working condition.