Biodiesel Questions

[s.e.hilliardTDI]

Greetings All.

Running a 2001 ALH Golf 5 Speed.

I live in Northern Ohio. My car has just under 100k miles on it. I am not the original owner so I don't know exactly what types of fuel have been used over the life of the car.

Since I have had the car I have used mostly BP brand ULSD with no issue. A few months ago I started running Stanadyne as a fuel additive (just the performance formula) seemed to run a little smoother.

I was interested in biodiesel and found a source for B20 at the other end of my commute. I am planning on changing the fuel filter right at 100k miles, so I thought I would run a tank or two of B20 to clean things out and then change the filter.

Here are my questions.
The car runs really good on the B20 blend I have in the tank now. Nice and smooth, easy starts, maybe even more power, feels as good as its ever felt.

Are there any modifications I need to make to the car in order to run B20 on a more permanent basis?? I read something about changing fuel lines? Can someone confirm that for me.

Will B20 work in my cold weather application (it can get pretty cold in Ohio in Jan. and Feb.)?? If I continue to add the Stanadyne will that make the B20 less likely gel the same way it would regular petro diesel? Or is it not necessary to add the Stanadyne to biodiesel?

Do the drawbacks of changing back and forth between bio and petro out way the benefits of using bio in the first place?? (If I take a road trip and can't get Bio I would be forced to switch back to petro diesel) Do I need to worry about injection pump leaks with B20/petro back and forth??

I would love to see this car go the distance. I am very impressed with it from top to bottom and am looking to be a very diligent owner.

Thanks for your input.

[chittychittybangbang]

The car will run fine without modificationss. B20 will work fine as long as they blend it correctly but an anti-gel additive will obviously decrease the chance of gelling.

B20 shouldn't cause leaking but it's possible on an older car. Mileage is low but age is 11 years old. B100 would probably cause some leaking if you went back to petro diesel. The seals could leak from age alone, if it happens I wouldn't let it deter you from doing what you want.

[biodieselbailey]

No problems with switching back and forth. I use B100 in the summer in RI and B20 in the winter. If i can't make it to get some bio I just fill up on petrol without a problem. My car seems to get louder when I have to run with Petrol. So I tend not to use it. Fortunately I work for a biodiesel producer so I'm never too far away from it.

The only problem I have seen in my own personal experience is that the filter gets dirty very quickly especially if you are switching back and forth a lot. Normally, when I change my oil, I change the fuel filter at the same time. This is probably completely unnecessary but my 2004 Jetta seems to like it.

Another thing to watch is fuel lines. I only have one line that seems to like to go on me. Biodiesel, being a great solvent, will dissolve the rubber in your fuel lines and they will get spongy. Just keep an eye on it. I had fuel shooting up like a geyser one night, girlfriend wasn't too happy about that one.

[nka21]

I thing biodiesel and winter are not good friends

[Garret]

Hi All,
I have become frustrated over the past few years reading all the threads posted by the ill-informed (at various forums) and would like to settle a few things in regard to biodiesel and its compatibility in a VW Jetta.

From the day when I first purchased by 2006 PD Jetta it was my intention to operate on 100% biodiesel (more correctly referred to as fatty acid methyl ester, FAME). In fact, soon as the complimentary tank of diesel was running low, I filled with homebrew with confidence. I spent over 12 years at a National Lab as a research chemist working on and analyzing alternative fuels derived from coal and other sources. However, my passion was biodiesel. I have about 40K/85K uneventful miles on 100% biodiesel and various mixtures so far in my Jetta and many tens of thousands in a 2 Super Duty Fords and 2 different diesel tractors and home heating (<=20%). Fuel filters are so clean in the Jetta that they NEVER NEED CHANGING WHILE RUNNING BIO AND HAVE NEVER BECOME RESTRICTED. Of course, I make a high quality product, often times better that the stuff commercially available.

Lets take a look at some other issues that are often brought up:

1. Fuel lines. I know for a fact that the fuel lines in my Jetta (not the entire cross section, just the inner liner that is exposed to the fuel) are comprised of a fluorinated elastomer, probably Viton. I know this because I analyzed the EDS spectrum acquired while imaging in a scanning Electron Microscope. Fluoride out the ying-yang. Conclusion: fuel lines compatible with biodiesel.

2. The freezing point of Biodiesel (100%) varies greatly with the feedstock "cooking oils" (triacyl glycerides) from which it is derived. This is particularly true of used cooking oils that are enriched in animal fats. Therefore, one may expect filters to plug anytime as exposed, unheated fuel system temperatures fall much below about 50 F. Yes, 50 F. Some batches may not freeze until about 28 F, but certainly not much below that. Another potential problem is the fact that biodiesel has a much higher water solubility and it is typically water washed. This can be mitigated by adding a small amount of isopropyl alcohol "dry gas" product when in doubt.

Yes, biodiesel is miscible in all proportions with petroleum diesel, although this will not appreciably depress the freezing point. The biodiesel will simply crystallize out of the petroleum diesel and clog your filter anyway. Therefore, your latitude will dictate your biodiesel use. At 40o N I can typically operate safely between May 1st and October 15 .

3.Combustion. Biodiesel had superior combustion characteristics and is well suited as a compression-ignition fuel. It also has lower emissions and less particulates. It is only mildly toxic. Your engine doesn't care. Also superior lubricity, although this isn't that important in the PD.

4. Why isn't everyone running biodiesel? Biodiesel will never entirely replace petroleum fuel. There simply isn't enough oil crop to go around. It is typically more expensive as it is a specialty product. Its also a bad idea to convert food crops to fuel.

5. Fuel economy. I can't tell the difference. I get an honest and consistent 42-44 mpg (mixed city/highway) on both bio and petroleum derived.

6. Biodiesel production at home isn't for everybody. Methanol is highly toxic in even small quantities, is absorbed through skin and is an inhalation hazard. Methanol is highly flammable and EXPLOSIVE when mixed with air and burns with a nearly invisible flame. It is also difficult for most people to obtain in quantity. Potassium (or sodium) Hydroxide is highly injurious to the eyes. And that soapy feeling when you wash your hands...that's your skin being saponified.

7. Why not just run filtered cooking oil. You can if you like and understand its limitations/consequences, coked injectors being one that comes to mind. Also, the viscosity of biodiesel is a lot closer to where the fuel system is designed to operate.

P.S. I joined this forum to obtain procedure for timing belt change. Used come along for engine support from above and floor jack/wood blocking below as suggested. Everything lined up perfectly. Removed camshaft sprocket and simultaneously installed new belt wrapped on camshaft sprocket and tensioner. Would also suggest that the hood be removed. Only 4 bolts and windshield washer plumbing. Made things much roomier for me. All told, 7 hours (includes time for a couple of pints). I used blue Loctite on bolts. The procedural writeup perhaps overly detailed. This actually caused me some confusion. All and all, much easier that separating a farm tractor. Mission accomplished. Thanks so much.

Garret

[chittychittybangbang]

How would you suggest the procedure be simplified? There are a few areas where you wouldn't expect someone to make a mistake but they find a way!

[Garret]

Don't get me wrong. The instructions are fantastic. I just found myself getting lost in all the details. I consider myself a fairly experienced mechanic. Perhaps I am taking for granted certain information that may not be intuitive for most.

What I would find useful is a task outline and a description of the tools needed to perform a task (not just the specialty tools) eg. "... motor mount bracket requires 16 mm, 6 point shallow socket for the uppermost bolt removal and a 16 mm, 6 or 12 point and a 6'' extension bar to reach the bolt through the fender well access hole..." I spend more time with tool selection than anything else. These fine German engineered marvels don't appear to be designed with the mechanic in mind. And I thought things were tight in late model American cars. I grew up working on 1970's pickup trucks that would allow one to climb into the engine compartment, sit on the inner fender and remove an exhaust manifold!

[williamgd2]

I appreciate your detailed explanation on the use and pros and cons of running biodiesle.I could tell your experienced with the production and use of it.I just tried my first tank of it and I am impressed.My millage increased immediatlly by 3 mpg hywy and it does run quieter and smoother.