I am intrigued by the possibility of making my own economical and environmentally sensible biodiesel fuel. After doing some reading about it, I have a few concerns, though. One is that I've read that the alcohol content in biodiesel tends to be hard on rubber parts in the fuel lines, engine seals, fuel pump, etc. Is there a way to distill all of the alcohol out of the biodiesel in the production process? Is the lye content a corrosion factor? Another is the fact that I live in Alaska and much of the year the temperature is well under 50F, leading to a coagulation/flow problem. How best to combat that? Are there any suitable additives which will keep it flowing?
Something else that just occurred to me is that, if biodiesel is a good lubricant for the fuel pump, as I've read in these forums, then does it naturally follow that plain vegetable oil, or filtered fryer grease, can be used in the crankcase? The viscosity seems similar. How about a totally vegetable oil-based engine? I have not seen any posts on that specific issue.
I would appreciate and and all informed comments on these issues. Thank you.

I suggest you read From the Fryer to the Fuel Tank : The Complete Guide to Using Vegetable Oil As an Alternative Fuel

and seek answers at the Biodiesel Discussion Forum