Where is the thermostat located on the 2.2 diesel? Usually, they are on top of the head but the housing that the top hose connects to does not look to me to be large enough to hold the stat. The lower hose housing on the pass. side looks like the correct size but I don't know and don't want to take the wrong housing off. I know some of the VW's are on the lower side but I'm totally unfamiliar with the Benz. Thanks

It's on the engine end of the lower radiator hose.

Sixto
87 300D^2

That's it, center left just below the exhaust manifold.