I recently aquired a 1993 300D that has been sitting for 1 1/2 years.I replaced the filters and fuel lines and got her running, but it is very sluggish at low rpm's. I plan to do a purge next week and adjust the valves. My dilemna is, there is a small check valve in the return line between the large fuel filter and the steel line that goes to the tank. When I was replacing the line, i removed this valve and could not blow through it from the filter side towards the tank. I could blow the other way. Seems like this is in backwards?
Any help would be greatly appreciated
Niko