Hi geordi, I too have not washed my last batches of bio. One thing to remember though is that even if you start with good quality oil you can still produce sub ASTM spec Bio. The stoichiometric ratio of MEtoh to oil is 13% but a complete reaction cannot take place with under ~20% because of the principle of reaction reversibility. It has to be forced to a completion with an overload of reactant. When <20% methanol is used you will still get a reaction with good phase separation but a large percent of of the product will be monomers and dimers. You mentioned in one of your posts that when you tried to wash your bio it produced mayonnaise. That is an indication of very poorly reacted bio with either a large amount of soap or mono and di-glycerides.
Even if your oil is very dry you can still make soap but the soap will have no emulsifying properties until you add H2O as in during the wash or when there is condensation in the fuel tank. If you are not washing the product give it enough time in a container open to air so that the alcohol can completely evaporate, preferably 6 weeks or more. If the fuel still has alcohol in it, it holds an almost equal amount of glycerin in suspension as well as some soap. I kept some beautiful fresh unwashed Bio in some mason jars and after several months it still looked clear with no sediment, but when I opened one to the air for a couple of weeks the alcohol evaporated and about 1/4 inch of glycerin settled out. I've had the same thing happen in my fuel tank as well when fresh unwashed fuel gets heated and the alcohol evaporates out.
Another mistake that some backyard BD producers is in discounting Biodiesel's ability to absorb and hold water. BD is not a completely non-polar compound, it is slightly polar on one end and does have a mild affinity for water. If the temperature remains constant that would never be a problem because it would reach saturation with H2O from the air and then not be able to accept any more. The problem occurs because as the temperature drops it's ability to hold water also drops. When that happens in the vehicle water settles on the bottom of the fuel tank and can cause various and sundry problems. Dino diesel will also do this but not nearly to the same degree. To avoid the water dropout I don't draw my BD from bottom of the holding tank, and if I know that there is going to be a steep temperature drop I just add a tiny bit of red bottle heet to the tank.
Now all that being said, personally I don't care if my fuel is sub spec in regard to bound glycerin or soap content because monomers and dimers burn just as well as FAME and only increase the viscosity by a very small amount and make the exhaust smell better too. I just make sure that all the free glycerin has been removed, not because it wont burn well or cause gumming of the injectors etc (contrary to the statements of some BD producers) but because it will saturate the filter and cause restriction if enough is dropping out of solution.
Anyone considering making their own BD or even if they just want to learn about it they should first read
ALL of the section on making it at infopop.
http://biodiesel.infopop.cc/6/ubb.x?a=cfrm&s=447609751
long may our CRDs live drinking all natural, delicious Biodiesel.
Edited for gramar