Clear, crisp winter mornings, and spectacular mountains all around - seemingly moved up to the edge of town every night for our viewing pleasure.  We are truly fortunate to live in such a pretty place.

Recently we have experienced an early cold snap for the Seattle area.  Overnight temperatures in the teens and single digits have signalled that it is indeed wintertime now in the PNW.  For some of us who have to park our Biodiesel rigs outside overnight, it adds at least a smidgen of worry with longer crank times (will that battery hold up?) and slower warm-ups (diesels do warm up slower than spark ignition engines).

And then there is the anxiety about what's in our tank?  Is it a blend of D2 and BD that is good down to these temperatures?  Or is my fuel getting cloudy - or worse yet: is there a layer of mayonaise-like goo forming in the bottom of my tank, just waiting to gum up my filter and starve the injection pump for fuel???

One way to "see into" your tank and fuel system, to know the state of your current fuel viscosity, is to keep a small bottle of fuel in your trunk.  In the morning, take it out and look at it:

Is it cloudy?  Is there "goo"?  Or is my blend adequate for the temperature and not going to cause problems down the road (literally).  Remember that you may be able to start and run your biodiesel powered car, and get all the way down to the freeway and merge on - only to have that sickening loss of power that indicates a plugged filter.  And some "quality time" on the shoulder of the road, talking to AAA and wondering why in a city of 2 million folk it takes 90 minutes to get some help...

If you do notice some clouding, you can head off problems by blending in some D2.  And maybe an anti-gelling addictive, too (though there are findings that the additive does not really work that well if it isn't in the presence of a little bit of D2).  Or, you can do like I did recently, and get a 5 gallon jug of D2, and bring it into your house to warm it up, and then blend it in with the cold stuff in your tank.  (I actually put the jug in my laundry sink with some really hot water to warm it up even more!)

Believe me, forewarned is forearmed, and having a view into what your BD might look like in that cold dark tank of yours can potentially save you a lot of trouble with a stalled car later on.

-kDavid

ps - thanks to Dan Freeman of Dr. Dan's for this tip to me years ago.  Dan goes up skiing every weekend in the winter, and this is what he does to make sure he's not trying to pump mayo through his fuel system...  ;-)