It might be time for a can or three of diesel purge. I could then rig up a temporary D2 tank to flush system and try a D2 only cold start on. This could eliminate or prove fuel source as the problem and it probably needs the diesel purge anyway!

I'm compulsive about changing inline filter as needed (I visually check it along with fluid levels every weekend), and change my spin-on filter with OEM stuff every 2000miles. I could go longer, but filters are a cheap and easy way to stay off the side of the road and prevent unnecessary wear and tear on my fuel system.

While I sense skepticism from some, it's nice to see a civil discussion about WVO feasibility. I've done 2 tank systems (converted an 82 240d, sold; converted an 84 190d, died a rusty death; and purchased a preconverted 1984? Ford Ranger, sold), and while very functional, I believe they are unnecessary given the toughness of our engines. I also dislike the idea of adding weight and complexity to the simplicity of our wonderful cars! Losing trunk space is a drawback for most systems too.

Our cars were designed to run on D2. However, the D2 available in the early 80s was 5000ppm sulfur! The crap we get now is 15ppm and provides piss-poor lubricity compared to the stuff of old and is ultimately not the same fuel. Additionally, I believe that MB owners manuals OK the use of blending D2 with unleaded a la 10-20% for cold weather operation. This is to say that I reject the notion that WVO is an unsuitable fuel simply because it was not what the engine was designed to run. If it's clean (this IS critical regardless of fuel type) and it's combustible and it'll flow, these cars will happily run down the road!

I have heard reports of piston rings getting gummed/coked up with carbon/WVO residue. While my compression numbers aren't perfect (larger variation than I'd like...), I think that simply having 432xxx total miles with the last 50xxx miles on WVO blend disproves the absolute theory that WVO=trashed engine.

All told, I probably have about 300,000mi on WVO with several vehicles reaching ~50,000mi on my blend. Knock on wood, this is the first problem I've ever had (other than clogged filters early on) with a fuel system. I credit good oil and a fuel filtration system half engineered by me and half purchased from Charlie Anderson of Greasel fame for keeping me largely trouble free.

Taking all advice and gonna see if I can use it to get the car back on the road again.

Thank you all for your time and expertise!
Brad