I know it would be here somewhere, but I can not find the PSI of the stock fuel pump for a 1985 300D.? I am running WVO with a one tank system in N. FL. and have had some good luck with the one tank system I have built. But, I have been thinking that I may need to increase the PSI of the fuel pump to help out the IP. Does this sound right, if so how much PSI is good? Would just another cheap pump along with the stock pump help, or should I look at the Regulated Pumps?

Just get a cheap electric pump from Napa and put it inline before the stock pump.

Are you heating your veggie? How are you filtering? Water content of the oil? A friend of mine is running a 1 tank in an 83 300D with a flat plate heat exchanger and has had no issues