Hatz 1B20,1B27,1B30,1B40,1B50 workshop manual.

This factory engine service manual has easy-to-read text
sections with top quality diagrams, pictures and
illustrations. The step by step instructions show you how to
complete any repair or overhaul, correctly and efficiently,
saving time and avoiding cockups. All specifications and
tolerances are listed. There is a troubleshooting guide and electrical diagrams.