The Jetta TDI Grease Machine

I finally did it. I decided to just go out and buy a nice car to run on veg. I figured, hey, why not? While older vehicles are more tolerant, newer vechicles give you more of a reason to do EVERYTHING RIGHT.

For me, doing everything right from the get go was a step by step process in itself. I had searched for months for a Volkswagen TDI between the years of 1999.5-2003. I decided on a 2003 Jetta that I found at a dealership in Southern California. The exterior was black, my favorite. The interior had cloth seats, the transmission was automatic, and it had just under 100,000 miles. I looked it over carefully and was driving it to my new home the next day.

But the work had just begun. Before I could even think about converting this car to grease, I had to make sure everything was working perfectly. I had the timing belt changed, the engine oil changed and got an oil analysis (great results), the compression tested (was in the normal range or about 450 psi per cylinder), the trasmission fluid/filter changed, the coolant changed, the water pump changed, the diesel fuel filter changed, and the fuel system cleaned. The glow plugs, air filter, Mass air flow sensor, vacuum lines, and electrical connections were all in good shape. The exhaust gas recirculation (EGR) valve and air intake were cleaned out as they are known to fill up with carbon. After all of this I had a car that did not smoke at all. A car that started right up and idled smoothly. A car that didn't burn engine oil or have blow by. I was ready to install my Greasecar Kit!

It took me about 25 hours over the course of a week to install the vegetable fuel system. My grease system consists of an 11.5 gallon aluminum tank in the trunk that is heated with the engine coolant through a copper coil, an aluminum fuel line sitting inside the coolant line all the way up to the engine bay, a heated filter assembly for the grease, a flat plate heat exchanger for higher veg oil temperatures, and two switching valves. Inside the car is an exhaust gas temperature gauge to monitor combustion quality and a boost gauge to monitor the turbo.

As far as the kind of oil I'm dumping into this car, I don't want to take any chances. I'm currently buying oil that's been dewatered and filtered down to 1 micron. I have met with the people I'm buying the oil off and their practices are acceptable to me. 1.50 a gallon is what I'm paying, and that still beats the price of diesel by a landslide.

Operating the greasecar system (especially on a nice car like the Jetta TDI) means a few important things:

1. Always wait until a few minutes after the engine temp. gauge reads 190 degrees before switching to vegetable oil.

2. Only use clean, dry oil and make sure it's being heated well prior to injection. (Hot engine, hot oil).

3. Always purge for approximately 30 seconds 3-5 minutes before you shut down. Running the engine hard before shutdown on diesel fuel ensures a good flush of all the veg oil from the injection system.

4. Do not sit in traffic for longer than just a few minutes. Combustion temps. can drop at this time and lead to incomplete combustion and carbon deposits in the engine.

5. Monitor start ups. If there is any smoke or it starts hard, there could be a problem and purges may need to be longer and/or diesel may need to be run a bit longer after the purge cycle.

6. Check the engine oil regularly and it never hurts to have an oil analysis done to see how the engine is wearing with WVO use. I plan on changing my engine oil every 4-5k.

....and now I get to drive a car that gets 40-50 miles per gallon, has plenty of turbo power, and is running a clean, renewable fuel. I'm so stoked it's ridiculous.

Taking Care of Your Vehicle

Sure, I drive a car that's the same age as I am, 30. But that doesn't mean I shouldn't try to keep it nice. I've developed a lot of respect for this WVO thing in the last year or so, and now that I'm burning a fuel that requires special attention to details I am realizing that I'm paying better attention to my vehicle overall.

The Benz may not be the cream of the crop when it comes to style, and I sure do get a lot of funny looks from people out on the road. But I respect these cars. They are built with a seriously strong Diesel engine that if taken care of can go 500,000 miles or more! I don't know how many miles are on mine because the odometer is at 150,000 and stopped working before I bought it. But it runs like a champ. Here are some things that I plan on doing on a regular basis:

1. Lube oil change: Every 3 months, which is about 3-5,000 miles the way I drive. Just got a fresh change last week.

2. Diesel Purge: A few times a year. I run it straight through the injection system and it's sure to clean out any possible carbon deposits and light coking. Using vegetable oil properly, I shouldn't be getting much of that crap anyway.

3. Checking tires, brakes, electrical connections: I just keep an eye on them regularly.

4. Transmission fluid flush: I recently drained the fluid from the pan. I didn't bother draining the torque converter. The fluid looks pretty clean now.

5. Radiator fluid: It was drained recently when I converted the car to grease. It's always good to have clean coolant.

6. Car cleaning: I like to keep it washed and for the most part clean. Like I said, it's not the most stylish and ofcourse it has it's quirks, but I can still do what I can to keep it clean.

These are some basic things to keep tuned on any vehicle. I plan on educating myself to be able to do the timing chain and other maintenance that is a bit above my level of expertise with cars. I own a Haynes manual which has been quite helpful.

Cash for Clunkers was a mistake. We can use older vehicles and learn to do our own repairs.

Have fun making other people hungry with your WVO exhaust!

Indirect Injection vs. Direct Injection

From my research of modern Diesel engines I have discovered there are two basic forms of fuel injection. Indirect Injection (IDI) is the first form and is found on most Diesel vehicles until around the mid 1990s. The fuel is mechanically injected through a high pressure pump to the injectors, a pre-chamber, then the combustion chamber. This is good for WVO users because the fuel is already starting to combust before the main chamber, providing more success for complete combustion. This allows more "forgiveness" to those of us who may have not had our fuel up to temperature before we switched to grease. These engines will combust colder vegetable oil easier than directly injected engines. The down side to the IDI is that you're not going to have the kind of performance you would get on a newer, directly injected engine. I currently am driving a 1980 Mercedes IDI and I don't have to worry or lose sleep at night that I'm going to ruin it, as the car is barely a step above a "parts car". However, I do try to always make sure my engine is at operating temperature before I switch to grease and I try to filter down to 1 micron when possible and do a hot pan test.

Direct Injection (DI) is the second basic form of fuel injection in a Diesel. In this type of injection system fuel is drawn with the pump, then when it reaches the injectors a set amount of fuel is sprayed at very high pressure directly into the combustion chamber. There is no pre-chamber to heat the fuel up further before combustion. Therefore, adequate heating of WVO is imperative to have success with this kind of vehicle.

With both DI and IDI engines it is a safe assumption to say that the engine should be warmed while burning Diesel fuel and only be switched over to WVO at operating temperature. The veg oil should be heated properly for success with complete combustion. Injecting grease into a cold engine (no matter what temperature the grease) can cause incomplete expansion of piston rings leading to what is called "blow by". The glycerin in WVO can get by the pistons and into the crankcase, causing lube oil contamination. Even with good practices, WVO users should change their lube oil at shorter intervals than those just running Diesel fuel alone. Diesel fuel should always be burned at shutdown, and the WVO purged almost completely from the lines. This is more important in colder climates, as the grease will congeal.

The Hobby of Greasing

I'd like to focus on cheap, safe, environmentally friendly, and easy ways to have fun with this hobby. The goal is to have the free grease pay the equipment off that you're using, and you can't do that after you've spent a thousand bucks on a kit only to spend another thousand on a centrifuge or the most efficient filtering system on the market. The car I'm running right now cost me $400 and the Greasecar Kit I'm using I already had on my previous vehicle. The kit has pretty much paid for itself after 10-15,000 miles on grease.

I do not use heat to pre-filter my oil. In the summer I don't think there is a need to anyway. If you're patient enough, your oil will settle naturally enough on it's own. I have run into problems in the past of running oil that was not settled or filtered well. It will clog your onboard filter and you'll find sludge in your tank. Not good.

Anyway, my system now is pretty good. I collect my oil either from restaurants or craigslist ads and dump it from the cubies into 55 gallon drums that were a waste product I got for free. I let the oil sit in a mostly shady spot for 2-3 weeks. The water/hydrogenated crap settles at the bottom and I can pump liquid gold off the top (I use a handpump I got for free). The liquid gold goes through 3 bag filters that sit inside one another in the sequence of 25 micron, 5 micron, and 1 micron. These bag filters are pretty cheap and can be bought from several places online (greasecar.com, dudadiesel.com, etc.). They will last over 100 gallons because the oil is so clean that goes through them. After that I soak them in baking soda, vinegar and water for 12 hours and use them again. I'm not sure how this affects the micron ratings though, so I'm only going to do that a few times before I get more filters. I also clean cubies out in the baking soda/vinegar/water to be used for clean oil that I can transport in my trunk for longer trips. Before the oil is dumped into my Greasecar tank I put a little on the stove at medium to high heat and check for bubbles. This "hot pan test" tells me how much water is in my oil. I am looking for a very small amount of bubbles to none.

My current vehicle is a 1980 Mercedes 300D. It was sold to me as a parts car and it runs like a champ. It takes to grease very well and the engine quiets down a bit when I switch over. I just parted with my two VW Golfs that have their own problems unrelated to grease.

The biggest enjoyment I get out of running waste vegetable oil in my car is the feeling of fuel independence. I can fly by gas stations knowing I'm burning a cheap and renewable resource that often ends up in sewers.