we have a 1979 300d mercedes 123 .we drove it and came home when we went to restart it will not fire.the starter turns over but will not fire. we have charged the battery it appears fully charged. we have good wind on engine and you can smell the diesel going into the injector pumps. we had a clicking noise that came from the right side of car before we engaged the motor the clicking noise is not there now and the car will not start. there is also a black plastic round cyclinder with a metal cap on it in the right fender well toward the back of engine it has copper wiring coiled and a lot of magnet running outside the copper coils it kinda looks like a magneto there are 2 hoses running to it from a box with a lot of vaccum hoses on it can you possibly tell us what this is. WE just changed the primary and secondary fuel filters last week so the filters are not plugged. We again primped it this morning and diesel came through the lines and dripped i drop per sec ans the book said. we have searched the internet and the hayes manual and asked anyone we know and no one knows why this car wont start. The nearest place that will work on a diesel mercedes to us is 2 hours away. any help would be appreciated to these back yard mechanics and one is a lady. thank you