Does the Td4 engine like bio diesel in small proportions ( 10 - 20% mix with normal diesel)?

UK diesel is already between about 5-7% bio, and this amount causes no problems. I don't know about 10-20 though.

I know the Evoque can take upto 10%, so I assume the Fl2 should be the same as they share engines  21MY Defender 90 S 3.0 D200

The main issues with 'biodiesel' and 'WVO' (Waste Vegetable Oil) is that if it's not made properly, that it will contain fat or particles which will soon clog up the oil filter and other susceptible areas. Be very careful about using it and if you do, please ensure that if you aren't 100% certain, that you are mixing it with forecourt diesel (percentages of tolerable WVO to Forecourt diesel are highly suspect) and that you have a reliable recovery service number handy.

Older mercs (c180/190) and older peugeots had no problem processing pure WVO. They could run on it neat. Modern cars are far less tolerant and many require professional modifications before using WVO. There's a German company who make WVO conversion kits (Elsbett) for many cars and they are the best without any doubt. It's around £700-£1300 (last time I looked) for a conversion kit and then you'll need someone you trust to strip your engine and install it all. Overall you could easily spend £2000 and that then negates any cost benefits you hoped to achieve by using WVO. Of course, with those pro conversions, you can use any mixture of WVO and regular diesel, so filling up is a matter of buying the cheapest sunflower, rapeseed etc oil you can find as it's all about compression. In laymans terms, if the oil is too thick your engine wont compress it efficiently and if it's too thin, it'll go nuts! If in doubt, don't!

As a road fuel WVO is a great alternative to forecourt diesel, however there are several issues which give rise for concern. I suppose from your point of view that your precious car would be your first priority. So if the bio/wvo has is thicker than regular diesel, your fuel injector nozzles won't be able to spray the correct amount and mixture (see WVO conversion kits which have the correct needles etc) . Another issue is that its use as a road fuel has pushed the cost of eg. Sunflower, Rapeseed etc oils up to forecourt prices. This happened at the same time and at the same rate as the UK govt realised that people were filling their cars up at the local chippy or ASDA. I used to pour litres of the stuff into a van I once owned without a moments trouble but the eventual cost negated using it.

I say that as a matter of principle, that if the majority of people who owned diesel motors used WVO, that the UK wouldn't need to 'stand shoulder to shoulder' with the US govts need to bring on the apocalypse prematurely by invading hot places for oil. So if it's a moral stance you're after, there's a strong one to be getting on with. If it's about economics, the argument is weak. If it's a two-fingers-up-to-the-govt thing, you're misguided as you'll be paying tax on supermarket sunflower oil anyway. If you can find someone who makes the stuff from ex-chippy oil, please make sure that they are not only using it in their own cars but that they'll also compensate you if their oil bungs up yer works. Get it in writing, in triplicate! Whereabouts unknown stop going to follow stream until reach civilisation stop message ends

My 2007 manual says up to 5% only. 
Hung like Einstein, smart as a horse.

I use bio diesel in my series 3 and find it makes quite a difference to the sound and efficiency of the engine ( a 2.5 NAS diesel). I suppose the TD4 is a more sensitive engine. However I see a sticky post about using 2 stroke oil in a TD4 (mixed with diesel!) and will go that route, unless someone has found that it's bad news to the TD4.

Thanks

The main differences I have noticed are:

- Much quieter diesel engine 'clatter' either at tick over or when driving.
- Without getting into mathematical equations, I have found an increase in MPG.

The main points to consider are:

- Is it financially viable to spend upwards of £6 for a litre of 2SO as a fuel additive/ lubricant? (when adding 300mls before filling a full tank of diesel, you will get one 330ml dose of 2SO per full tank of diesel. Or a total of 3 doses of 2SO per liter of 2SO.) You could change from using standard diesel to using a more expensive forecourt option. I find the more expensive diesels equate to higher MPGs per tank. So over all it's a trade off. I still use regular diesel and add 2SO because then I know exactly what i'm putting into my tank.

- Nothing has happened to my car since I started to use 2SO in my tank. The random noise I reported in another thread was there on the day I bought the car and it had just been serviced by Caffyns. Whereabouts unknown stop going to follow stream until reach civilisation stop message ends