Path of fuel through a 1985 123 wagon

[MeinGreaseCar]

OK.. I've owned a couple of diesels. 1985 126 and a 1991 124.

I just inherited from a friend the passed.. a 1985 123 wagon. He has the 'grease car' kit on it. He's had troubles over the years (i'm not sure if the install is bad or not)

I'm trying to figure out where he strayed from factory. I think I can address the grease issues later, as I make home brew biodiesel. Running that unwashed and heated is my plan, and it would be MUCH more forgiving that stuffing the fuel lines, filters, and tank screen with sludgy, poor quality grease that he did on MANY occasions.

Anyway. My question is thus.

I'm ASSUMING that the diesel lines to and from the tank are this way (line the tips up at a 45 degree angle is the 'return to tank' line)????

The path of fuel in my other cars was from tank, through pre filter, through lift pump thru filter housing, through injector pump, then injector return line back across top of filter housing with the outlet back to above bent line return to tank.

That is NOT the way this 123 is at the moment. It goes through the filter housing, then lift pump, then injector pump.

I'm having trouble with priming it. I'm sure the small hand pump isn't in that good of shape.. I was thinking of using air to pressurize the return line (and tank) a small amount to get flow going again.

I'll deal with the grease system later. I'm just trying to get back to diesel operation. Car was running fine, but when I got messing with the grease system (trying to figure it out) I lost prime and have been swearing ever since.

Thanks Much.

JP