Hello. I caught your post by accident and I will throw in my 2 cents worth on the questions that I have experience in. There are a couple of other guys who are members who are much more experienced than I am.

We don't have extended cold here in south GA, so I have had success with mixing 20% diesel with 80% biodiesel. Most of my oil is soybean and I plug in my block heater at night. .

I use isopropyl alcohol and I think this is the standard. It is my understanding (and experience) that the oil does not mix well with Methanol, so your titration may appear to be lower than it actually is. I.e. isopropyl will be more accurate. When I have used methanol, my titrations were very low and I had a bad batch occasionally due to the low rates of KOH the erronious titration called for.

I am using 9.0 plus the titration. I went through a period of bad batches (along with others in my area, and others who commented on biodiesel forums) and it appears the KOH can degrade when exposed to air. Therefore, I increase the KOH from 7g/L to 9g/L. I hate bad batches that I have to re-run.

I am not an expert on using unwashed biodiesel. I do know that unwashed biodiesel that has not been through a process to remove the methanol does contain glycerin and soap in suspension. Glycerin and soap (particularly glycerin) will produce a significant amount of carbon which could damage injectors, and perhaps even bearings as it contaminates the oil.

Some people remove the methanol from the biodiesel, allow it to settle for 2-3 weeks, and then run it. I can say from experience that it will clear up into some beautiful fuel, but I still use a low rate of Magnesol as a dry wash to finish my fuel.

Good luck: You are officially addicted now.