I've been sharing your veggie car info with my 13-year-old grandson. He wants to know if frequently replacing the filters would be the expensive part of the veggie car.
LARRY'S ANSWER:
Currently my 1978 Mercedes Benz 300D veggiecar has three fuel filters on it.
The first or primary filter is a small disposable plastic filter which filters out the bigger pieces of crud. This filter originally came with my Mercedes and costs three or four dollars at most auto parts stores.
My second fuel filter (which is not original to the Mercedes) is a Racor 500FG filter with a 2 micron filter element. I added this filter because vegetable oil often has many particles in it and I wanted to run the oil through an additional filter to filter out the smaller particles down to 2 microns. Since a single strand of hair is 300 microns, 2 microns is pretty small. These filters and elements are available at many marine supply stores. The elements cost eight to twelve dollars. The filter setup itself costs about $150 new, but you can buy them on eBay for about $60.
The third fuel filter is the standard Mercedes fuel filter, called a "secondary filter". Cost is ten to twelve dollars at most auto parts stores.
All three of these filter elements need to be changed every 1000 miles or so, or when the car slows down when going up hills it used to take easily.
This is the setup recommended to me by fattywagons.com and it works very well.
The larger two filters should be filled with Dexron 3 automatic transmission fluid, and the air bled out of the fuel system before restarting the car. The automatic transmission fluids has lots of detergents in it that will help clean out gummy deposits. And, strange as it sounds, it will burn in a diesel engine.
This is the system I drove across the country and back, using waste vegetable oil from restaurants.
The system I use at home to prefilter my veggie oil consists of a 55-gallon barrel and a 5- gallon bucket. The bucket has hundreds of holes I drilled in it. I carefully cut a large hole in the 55-gallon barrel to fit the 5-gallon bucket. Now the bucket with holes fits into the top of the barrel, and the wider rim of the bucket rests on the top of the 55-gallon barrel, fitting snugly. Into the 5-gallon bucket, I place a large denim cloth, though which I filter the veggie oil.
This is what I use at home to prefilter my veggie oil. It works very well, but kind of slowly. I keep this setup in my garage to get the water, leaves, bugs, etc out of my veggie oil.
Now, on my cross-country trip I used another method, because a 55-gallon barrel was too large to fit in the trunk of my car.
I purchased a 6-gallon beverage dispenser (with a spigot) at a local restaurant supply house. The 5-gallon bucket with holes fits nicely into the 6-gallon dispenser, leaving three or four inches of space for the oil to filter down into the dispenser.
Also, instead of a denim cloth inside the bucket with holes, I use a flannel pillow case, which fit nicely. The flannel pillow case filters the oil more quickly, but not as thoroughly, than the denim. So I use it only on long road trips, where I have to filter more oil away from home. Also, the flannel will develop holes eventually and need to be replaced.
These systems are what I am currently using to filter my veggie oil. I'm experimenting with a pump and filter setup to prefilter the oil more quickly on long trips.
Does anyone out there have a quicker way to prefilter veggie oil on the road? If so, please send me an email.
Larry