hello out there. I'm trying to troubleshoot a smoke problems with my 1973 220d. The main problem is that I don't know what to expect from these cars. After installing the updated glow plug system, one rocker arm/shaft assembly, and removing the injectors to check them out, the car runs great and steady. At idle, the smoke is not bad at all, but if I goose the throttle, black smoke billows. It puffs smoke pretty good when accelerating and under load. From what I have read, this could be the vacuum pump or fi pump diaphragm. I had the back off of the pump and the diaphragm "looked" good. I see some oil in the large vac tube but it looks old, like the pump was repaired in the past. Anyway, I just ordered a pump rebuild kit but if you have any ideas, please let me know.