I have an air bubble issue on my '86 190D when running on diesel only. With the air bubbles come nailing and stumbling. What I'm wondering is how everyone puts together their fuel system. Stock, the diesel comes from the tank, through an inline plastic filter, in to the lift pump which pushes though the main filter, and in to the IP.

I have changed it so that the mechanical fuel pump feeds directly to the IP and pulls though the diesel filter (not ideal). This is so that I can feed WVO to the mechanical pump without going through the diesel filter. I have a small facet pump coming off my veg tank.

I'm wondering if anyone has had to put an electric pump on the diesel side to help push though the filter to eliminate air bubbles in a pulling though the filter scenario.