Today it was 5 degrees below zero with overcast and occasional flurries. No matter, I made a clamp to fit the Norvel .15 to simulate running at normal temperatures. First, a run was made with stock, 40/40/20 fuel to establish base settings for the CR and needle. The engine ran well with no sign of distress due to the temperature.

Next I tried to get a start on 100% Biodiesel. Tried and tried and tried. Using a 50/50 ether/oil prime, I got healthy, prolonged burst of 5 seconds or so many, many times but no go,, no matter what. It appeared that the engine WANTED to run but at a crucial moment, it ran out of ether fumes and quit. Next I added Amsoil cetane booster in increments from 1/2% to 4%. I got more prolonged prime bursts of up to 15 seconds but that was it.

Next to try was 20% kerosene and 80% Biodiesel. After much effort, I had a run. It took nearly a dozen, healthy, prime runs. The compression was turned out a small bit from the previous attempts. The needle was turned out a full 2 turns. But it was ROUGH. Then I added 1% Amsoil CB and we had a much smoother run. The needle was turned in a half turn and the compression screw out an eighth of a turn. Lots and lots of smoke, BUT the power was on par with a stock fuel as well as an all kero/castor fuel. The needle WAS turned out by a full one and a half but the power was there. So are we burning ANY Biodiesel? I suspect so and I'm hoping to do an exhaust oil collection test as soon as I can. Soon to be posted to YouTube, note how sensitive the compression was. At the end, I turned it in a bit producing a sag. Taking it back out brought up more power but then, a sudden flame out. This was typical. I'm speculating that poor atomization of the thicker mix is the culprit.

Somewhere it was speculated that MotoMaster's cetane booster was mostly Stoddard solvent. Pennzoil's Gas Mileage Improver has that listed as a prime ingredient so I tried some at 2% on an all kero/castor mix. Nope, something wrong. Didn't work. Notably, none of my calls to any of the manufacturers about their ingredients has ever prduced a response by phone or email. Maybe I'm wrong but I can't blame them for not wanting to elaborate too much about their products.

But, I just came cross these good folks.

http://www.renewablelube.com/

What do you know. It had to happen. They make a soy based, cetane booster along with veggie based lubricating oils.

I've emailed them for more information about the use of their products in our engines.