The Albuquerque Biodiesel Project's intent is to use this vehicle as a means to explore, and document the process whereby a standard diesel automobile is transformed to run on biodiesel.  We intend to document the results of this change in order to provide a real world example of what it took to get one particular vehicle transitioned to biodiesel.  We hope to be able to provide many more examples as time goes by.

The first step in this process was to have a gas analysis performed to get some baseline information on the emissions, as well as acquiring some gas mileage data for the car running on standard diesel.  I made the mistake of taking the car in for a gas analysis before having any work done on the engine, and after paying the nice gentleman $85.00 for the analysis he informed me that the car was not running well enough to provide a proper baseline for what I wanted to do.  I parted with my money, swallowed my dissapointment, and took the car in to have the necessary engine work performed.  The guys over at Wittler's Automotive at 121 Elizabeth NE adjusted the valves, replaced the rubber fuel lines, and installed a clear inline fuel filter, which should have been part of the stock configuration but was missing somehow.  More on the importance of this filter, and the large canister fuel filter below.

We began anew by running 6 full tanks of standard diesel in order to collect some baseline gas mileage data.  You really can't drive in Albuquerque without using I-25, and I-40 to get from Point A to Point B, so we drove the car a combination of city and highway miles, but the highway miles usually consisted of less than 2 - 3 miles at a time.  The results we obtained are as follows:

Tank 1:  21.7 mpg
Tank 2:  21.2 mpg
Tank 3:  22.6 mpg
Tank 4:  22.9 mpg
Tank 5:  22.8 mpg
Tank 6:  22.6 mpg

Average:  22.3 mpg

This is actually pretty crappy gas mileage for a 3.0L diesel motor.  It should be getting mileage in the high 20's to low 30's.  I suspect I still have some adjustments to make to the engine tuning, however I don't want to mess with it until I have at least gotten data for the car running on B20.

About halfway through the gas mileage checks I took the car back to Bernie over at Double Gear Automotive, 5101 Gibson SE for another gas analysis.  By the way, Bernie is the only person around who can perform a gas analysis on diesel motors.  He is not that familiar with these old school diesel engines, so could not tell me for sure that the car was now running at it's best, though it was running much, much better, and cleaner than before.  We now have a nice baseline for comparison of the before and after emissions.  I do not profess to completely understand the plots we obtained so I think I will have to wait until we get the B20 gas analysis to compare whether or not the engine emissions have improved or worsened.

B20 is a standard blend of 20% pure biodiesel with 80% petroleum diesel fuel.  Biodiesel as currently sold in the United States is designated as BXX, where the XX represents the percentage of biodiesel blended with standard petroleum diesel i.e. B20, B50, B80 and B100.  B20 is the only blend available here in Albuquerque, and only at Ever-Ready Oil company, 1200 1st Street on the corner of 1st and Mountain, although you can get B20, and B100 in Santa Fe at Amigo Mart/Baca Street Biofuels, 1229 Cerrillos Road.  These are currently the only locations in the neighborhood where you can purchase biodiesel.  There is another outlet for BioDiesel at Rio Grande BioFuels in Anthony, New Mexico, but they are about 300 miles from here.  You can find a great listing of retail stations in other parts of the country at the Biodiesel.org - Retail Fueling Sites WebPage

Converting a vehicle to run on biodiesel requires only a small commitment from the owner.  The very first steps you must take are:  change, or add an inline fuel filter to your system, (preferably clear) and replace all rubber lines in the fuel system with Viton fuel lines.  As biodiesel has much better solvent properties than standard diesel a common phenomena that has been observed is that of biodiesel dissolving, not only the rubber fuel lines, but the deposits that have accumulated in the bottom of the fuel tank, especially in an older car such as this.  An older car who's entire driving history consists of New Mexico mileage will most likely have much sediment at the bottom of the tank.  So your first chore in making the change to biodiesel will be to change your fuel filters often!  This problem becomes much less pronounced the newer the car is, and cars manufactured after 1992 utilize Viton parts instead of rubber, but I would advise some fuel filter maintenance discipline even in these newer cars at least until you determine how the sytem is going to react.

Another option that some folks around the country are sold on is to remove and clean, or replace altogether, the car's existing fuel tank.  This step will virtually remove any concern of stirring up the grunge in the car's fuel system.  This option, however, is fairly expensive, and kind of a pain.  I have opted for the fuel filter method, and I guess I will see in the next few weeks whether or not this was a wise choice.

I highly recommend acclimating a car to biodiesel by starting with B20, or even a half diesel, half B20 mix.  Please DO NOT start an older car out on B100.  You will be absolutely overwhelmed with grunge from the tank, and if you wind up clogging your fuel injectors, as I almost did, you will be most unhappy.

I filled the car up with it's first full tank of B20 on 9 September, 2006.  I gathered from my research that one needed to change the fuel filter at least every tank full of B20, however on 20 September, 11 days after filling up, and just above the 1/4 mark on the fuel gauge, the car would not start.  It took me about 10 minutes to get it to run and then just barely so.  I got it running well enough after a few more minutes to get it to idle then I checked the fuel filter.  There were large chunks of grunge in the filter element, and one or more of these had obviously gotten through to the injectors.  I changed the filter, and then drove the car to the station and filled it up.  I had to resort to putting some standard diesel injector cleaning additive in this tank of fuel.  After several hours of driving the injectors cleared and the car began running normally.  Whew!!  By 22 September (3 days) the new filter was once again completely clogged, and I changed it out.  This filter lasted until 26 September (5 days) when it was changed out.  I'm getting pretty quick about this, and can now change out the filter in about 15 minutes.  Keep in mind that the car has been running just fine since the first filter incident, but to avoid any difficulties I am changing them out when they get dirty in order to avoid experiencing another problem.

After the clogging incident I decided to fill up the tank when it was between 3/8, and 1/2 full just to be on the safe side.  Remember, if you clog your injectors badly enough you will not be happy with the cost of getting them cleaned.  I think it best not to take any chances with your engine, or your budget.

This filter changing activity (every 3 - 5 days) continued through 4 tank fulls of B20 until the filter change I made on 5 November.  I changed out the canister filter at this time, and on 1 October, and 8 October as well.  When changing filters on 5 November I noticed that the fuel entering the filter was actually clear.  Up to this point the fuel appeared very grungy and dirty, though I did notice a steady clearing trend.  The next time I felt compelled to change out the inline filter was on 26 November;  21 days!! Yee Hawr!!!  The fuel entering the filter is now perfectly clear without a trace of grunge.

I am now on my fifth tank of B20, my 11th inline filter, and my 4th canister filter.  I do believe this odyssey is over.  I had understood that it took about 6 - 8 weeks to acclimate an older diesel car.  This one took 10.5 weeks to thoroughly acclimate, and it looks like I could have routinely changed out the inline filters once a week.  Just 15 minutes on a Saturday morning.

Total time to acclimate car:  10.5 weeks
Average time between filter changes:  7.4 Days
Filter cost:
11 inline filters @ 3.88 = $42.68
3 canister filters @ 9.57 = $28.71

Total cost $80.96
Here are some standard claims made about the use of biodiesel along with my initial impressions:

1.  There is a reduction in performance, about 15%, due to the lower energy content of biodiesel.

I have not noticed any reduction in performance at all, in fact the car seems to reach it's shift points more smoothly than before, and seems to accelerate more efficiently.  My perception is that the car is every bit as powerful as it was before the change, and that any loss of performance is not perceptible, at least by this driver .

2.  Lower emissions.

I won't get another gas analysis until I run on B20 for awhile.  I want to wait until some point in time after my fuel system has been cleaned up and the motor has been running on clean biodiesel.  I have noticed though that the typical diesel start-up-cloud-of-smoke has been greatly reduced, and that there is virtually no smoke from the engine while driving.  The engine does smoke a bit while idling, which is probably due to it's still needing some additional tune up.  I should have another gas analysis in about 6 - 8 weeks.

3.  Lower gas mileage due to the lower energy content as described in #1.

Gas mileage results so far are as follows:

Tank 1.  19.8 mpg
Tank 2.  21.2 mpg
Tank 3.  Unknown. Speedometer broke.
Tank 4.  21.1 mpg

Tank 4.  18.22 mpg

Average:  20.08 mpg

So far looks like approximately 2.07 MPG less on average.  I will continue to post the results at each fill up.

I am going to start getting some pure highway miles in the near future, but I wanted to get the fuel system cleaned out first.

4.  Using biodiesel gives you a quieter, smoother running engine.

The car exhibits a distinctly rougher cold idle when first started in the morning, but once the engine has reached operating temperature it is more smooth and quiet by far than when it was running on diesel, and once warm the idle smooths out and the engine sounds just like a new motor does.  The highway performance is phenomenal.  You can barely hear the engine running!  I am most pleased so far about this aspect of switching to B20.

5.  Better smell.

Absolutely a better smell.  The odor from the exhaust is actually almost pleasant, and although is does not smell like french fries, as many people are fond of believing, it certainly has what one might describe as an organic character to it.

So far I am most pleased by the results of switching to B20.  I am a bit concerned about the amount of grunge being dragged up from the tank, but I will simply have to maintain my filter discipline until this clears up.  I expect it will take another 4 - 6 weeks for this to begin to abate, which unfortunately means perhaps 10 - 12 more filters before I am done, although the problem should begin to clear up as we continue driving and I should begin to get some longer filter life.  I may come to the conclusion that cleaning, or replacing the tank would have been the more logical route, but the entire purpose of this experiment is to explore the process and provide real world feedback and advice for others who want to make the switch to biodiesel.  Perhaps I will have some advice to offer soon.  It costs approximately $200.00 to clean or replace a fuel tank, and I may spend around $50.00 to $70.00 dollars on filters before I am through.

I am most certainly pleased with the performance and sound of the engine.  I really do get the feeling that the engine is becoming happier as it runs on this fuel, and I still cannot get over the smoothness of the engine's operation.

As it is approaching winter we will not make the change to B100 as soon as expected.  We are going to start experimenting with higher percentage blends of biodiesel as winter progresses in order to see if we can determine a blend that will be suitable for the Albuquerque cold weather environment.  I still have some study to do regarding the gell problems people are experiencing with biodiesel, and will discuss this in more detail in the near future.

I guess that is about it for now.

If you have any questions regarding BioDiesel, or vehicle modifications, or anything you don't understand, please send an email to at the Albuquerque Biodiesel Project.  I will try to give you a coherent answer, or at least try to point you to a resource which will be of help.

Also please sign up for email alerts that I will provide from time to time regarding our progress and activities.  I am always on the lookout for interesting items, and new developments regarding biodiesel and alternative energy and would love to be able to pass them on.

Paul Sment Albuquerque BioDiesel Project