This report covers the technical specifications, maintenance procedures, and troubleshooting guidelines for the Mercedes-Benz OM646 engine, based on workshop manuals and technical training documentation. 1. Executive Summary: Mercedes-Benz OM646 Engine
This is the heart of the manual. It covers the removal and installation of the engine, cylinder head removal, and piston/rod service. Mercedes Workshop Manual Om646 Engine
The OM646 is a family of four-cylinder, turbocharged diesel engines produced by Mercedes-Benz from roughly 2002–2010 and used in models such as the W203 C‑Class, W211 E‑Class, and various Vito/Viano and Sprinter derivatives. It succeeded the OM611 and preceded later common‑rail iterations; it’s a wet‑sleeve, aluminum‑block design with a cast‑iron cylinder liner/insert or integrated liners depending on sub‑variant. The engine is valued for durability, torque delivery, and relative simplicity compared with later high‑pressure common‑rail diesels. Engine Mechanical (Group 01) This is the heart
Twin Counter-Rotating Balancer Shafts: Standard on most passenger car versions to ensure smoothness. What a Mercedes Workshop Manual Covers It succeeded the OM611 and preceded later common‑rail