Friday, April 20, 2007

I'm an idiot.

Earlier in the trip, I was concerned about the quality of the vegetable oil I was putting into the tank, and the effect on the vegetable oil fuel filter because it seemed as if we were going through them at a horribly fast pace (about one filter for every 500 miles or so).

To give the non-veggie oil driving public a frame of reference, this is an absurdly fast pace - these filters should last 3,000 to 5,000 miles. We were going through filters roughly an order of magnitude faster than expected - how bad is the oil we're using? I'm using oil that looks good, and I am filtering it - just not well.

At first, I attributed the problem to my less-than-stellar approach to vegetable oil filtration, but then I began noticing a pattern...

The filter seemed clogged whenever the tank was nearly empty (about 1/8 tank left). In fact, the filter seemed to "clog" at the same tank level every time - 1/8 tank. Hmm, loss of power and acceleration whenever the tank gets low... Hmm, what could possibly be going on?

Is 1/8 tank a magical number?

I pondered this for some time, and then I tried an experiment:
While driving around D.C., the tank got low and the car again exhibited "clogged filter" symptoms, so I switched to the diesel tank until we returned to Miss N.J.'s house. The next morning, I refilled the veggie oil tank (without changing the filter), and much to my delight, the filter was no longer clogged.

That's right kids, when the veggie oil tank reads 1/8 full, it's actually completely empty. I'm an idiot. With a jumbo shipment of fuel filters.

We now have about 14 fuel filters - enough to travel 40,000 to 70,000 miles, and I threw away 2 or 3 perfectly good fuel filters somewhere along our route.

A plethora of fuel filters anyone?