77280SE Dont want to Start
 

I am new to this forum and this is my first benz, so please be easy on me.
The car will start up and run fine if I pour some gas in the intake opening, but it wont start with out the gas! Here is something that may or may not have anything to do with it,the car does not have the original gas tank, it has a fuel cell like a race car.Any help would be great. The car has the straight 6.
Also I do not have a breather for this car. I dont know if that could have anything to do with it