French fry oil as fuel...

Hey everyone,
I'm relatively new here and I'm not sure if this topic has been discussed before. There have been reports in the media about using used cooking oil or vegetable oil as an alternative fuel. A taxi driver in Berlin is close to 500,000 kilometers using it, and he hasn't had any problems! However, with a gasoline engine, the fuel injection system is generally not as sensitive as it is with my Audi 1.9 TDI.
Right now, I'm thinking about the second one. Fuel tank, or its heating system (cooling water?), as well as the switchover between diesel and oil.
With fresh oil, there shouldn't be any problems. I once poured in 10 liters from Aldi, and it worked fine. There were still about 8-10 liters of diesel in the tank, so it was a reserve amount.
The second 'difficulty' I see is in using used oil, or in reprocessing (cleaning) it. Has anyone ever thought about using a centrifugal filter?

By the way, this is NOT tax evasion or anything like that, because cooking oil is a food product and has already been taxed. How you use it is your own business!
Therefore, you can save a SIGNIFICANT amount of money, not just if you are a frequent user. Perhaps some people might be interested in exploring this topic further.
Goodbye.
Best regards, Ralf

Hello B4,

Try using the search function with the keyword PÖL.
That should satisfy your thirst for knowledge.

Best regards,

Hello Ralf,

Do you see that www.fmso.de is the largest municipality of its kind in Germany?

Best regards, Ralf.

I converted an A4 (AFN engine). I can provide more information if needed.

'But I think the core competency here is different. You might want to check out www.fmso.de or www.fatty-fuels.de. However, please read and research thoroughly before posting, otherwise you'll likely receive some silly or unhelpful responses!'

Has anyone ever converted a gas tank to run on propane? The idea of getting free fuel by filling up at the Burger King across the street is certainly tempting. The warranty will eventually expire, too.

I was thinking of doing it like this:
- 2. Spare tire well with integrated tank.
- Cooling water/oil heat exchanger.
- a pair of solenoid valves and hoses, and a filter.
- A dedicated pre-feed pump for the oil tank, ensuring that the oil is circulated even when the heat pump is not in use.
- "Injection" of the fuel after the diesel filter in the engine compartment.
- possibly an electric pellet heating system.
- The first and last kilometers will be covered with a Dinosaft.
- In the basement, there will be a filtration system for the oil used in the fryer.

Is that possible? And what does the TÜV (German technical inspection agency) say about such a modification?

'It might be possible. There are some tuners who supposedly handle this quite well with the PD engine. However, it's a bit expensive, starting from around 3000 euros. Your solution definitely works with a VP TDI. With a PD engine, you'll need to put in a bit more effort. I drive my 96kW PD with a 50:50 mix. It's initially a bit safer. Will I convert it? I have no idea.'

TÜV? Yes, a dual-tank solution must be registered, as well as the additional heat exchangers!

Where does the bottleneck lie with PD? The increased workload for PDEs shouldn't be much higher than for ESPs with VP. Or am I wrong?

Don't be fooled by that! The printing conditions are quite different. And a higher viscosity makes a significant difference.
How about flushing the fuel lines, etc.? That's all a bit more complicated and time-consuming than with the VP TDI.

hm,
I'm getting more and more unsure... A 70/30 blend would probably still work, but I don't want to risk damaging the diesel pump! 'And I definitely won't be bringing anything with a star on it into my house!'
I still need to learn a bit more.

Once I've gained more experience, I'll definitely continue using it.
Best regards,
Ralf

It is also possible to achieve 100% conversion to heating oil with a two-tank system after switching to heating oil. The most important things are proper preheating and intact nozzles .

Preheating the reactor is straightforward. I'll figure something out; thermodynamics has to be good for something. A coolant/reactor heat exchanger is essential. Then, we could potentially add some electrical heating. Maybe even with a Peltier element to improve efficiency. To interpret this, I first need all the flow rates and other relevant data.

Flushing the fuel lines is also giving me some headaches. I don't want to have to pump a liter of fuel into the diesel tank every time I switch. That's why the shared hose sections should be as short as possible. I need to do some more research on the flow rate of the diesel pump and the amount of diesel in the reservoir.

The load on the injectors depends heavily on the driving style. The pressure increases with the engine speed. Normally, I drive on the highway at a maximum of 3000 RPM. When accelerating from a low RPM with full throttle, only the injection duration changes, but not the pressure. While the Nock profile remains somewhat steeper towards the rear, the pressure increase is likely to be lower than that which depends on the rotational speed.