I did check my clamps but I'll go over them again. Is there an easy trick to determine if a connection is leaking from the vacuum?

I'm not sure what a purge mode to prime the system is, but I assume you mean sending the return diesel fuel back to the veg tank to thin the WVO? I've already helped my WVO by starting the system on a 50/50 mix of new SVO and diesel fuel. I figured this would help get the system going.

I run a hotfox and heated filter unit, both by engine coolant as well as the vegtherm. The car has been sitting in a heated garage the entire time I've been working on it. Yea, it's a real benefit to have a heated shop!

Any other suggestions?