I've been running wvo in my 616 for about a year now with no major problems. (it did recently eat up the seals in my bosch upgrade primer pump) However, I have invested in an Elsbett conversion kit. Here's the website if you're interested: http://www.elsbett.com/us/online-shop.html

I like to let my oil dry first by gravity. I pick up my oil from an oil drum located in an underground parking garage. I know when the restaurant throws out the oil, so after about a day or so I stop by to pick it up. I use a hand crank rotary pump, and I pump all my oil right off the top. I never go deeper than about 2/3 of the way down the barrel. That way, all the water and all the crap sinks to the bottom, and I'm left with fairly pure oil. Then it goes to my filtration system at home where it is first heated using a water heater element suspended inside an oil drum. If the oil has water in it, you can hear it crackle. I bring my oil up to 250 degrees fahrenheit. If the temperature hovers around 212 degrees fahrenheit (the boiling point of water) for a long time, then you know that the oil has too much water in it.

As for particulate matter, I pressure-filter my oil in a 5 micron whole house water filter. I actually wouldn't really worry about this too much, since whatever particles you don't catch yourself will just get caught by the fuel filters in your car. It's just that whole house filters are much cheaper, much bigger, much longer lasting, and much easier to change than the fuel filters in your car.

Another thing that many say is important is to do a titration test, although I have never attempted this myself.

Whatever you do, it is probably a good idea to check out this website: http://www.journeytoforever.org/biodiesel_svo.html
It was an excellent resource for me when I began vegetable oiling.

good luck!