Tax free fuel for diesels

[Surfer]

Have a look at http://www.biotuning.co.uk/Home.htm. Seems that you can now use vegetable oil in your diesel without having to pay tax. This brings the price down to about 60p per litre when bought in bulk, i.e. 20 litre can..

 

[rob_jax]

Ian,

Not a great idea to use veg oil, even mixed with pump diesel, in a modern TDI or CDI engine - the viscosity is way too high (even when heated) for the injectors to work properly.

Converting the veg oil into bio-diesel is the right way ahead for those cars - but you need to process the oil and this needs a bit of skill and knowledge (easily obtained) - and you end up with a fuel that is similar in viscosity to diesel, and has great lubricating power - protecting the injectors and high pressure pump more than supermarket diesel

OK to use veg oil with older generation engines - pre-common rail and pre-ultrahigh pressure injection technology era - these were relatively crude devices and the poor spray pattern from the veg oil doesn't hurt the engine performance.

Robert

 

[Surfer]

Which is the main reason why I traded in a 20003 Volvo S80 D5 for a 1997 Toyota Hilux Surf 3.0 litre two years ago, however I understand that the S80 2.5 diesel should not have a problem with SVO.

 

[rob_jax]

Ian,

No modern diesel engined car - Euro III or Euro IV emission standard - is compatible with straight veg oil (SVO)

The viscosity of SVO is way too high for the high pressure pump and the injector spray pattern will also be wrong - too viscous to spray as a mist - power and fuel efficiency will be affected, and emissions will be higher

SVO has a relatively short life before it starts to go rancid and release organic acids and gummy residues - neither of these are good ideas in a fuel system.

Conversion of the SVO to bio-diesel is a much, much better route.

Robert

 

[Robert_374242026]

Regarding mixing of fuels takes me back 100 years ago in the RAF, the MT guy's who had motorbikes use to put a few galls of Av-terb(aviation spirit for aircraft)into the lorries and take petrol out for the m/c,they reckoned it made hardly any differance.

 

[spj]

Hi Ian,

Vegatable oil is only any good for old rotary type non electronic fuel pumps, modern diesels will not run properly on it and will be expensive to repair if damaged by it.

Alternative diesel fuels will come, but they are not ready for the newer engines yet.

spj

 

[Surfer]

I agree about common rail engines etc but what is classed as modern as a lot of people with Discos and Toyotas haveb been using SVO for a number of years with no ill effect. I can pour veg oil directly into my fuel tank with no ill effect and can use up to a 80/20 mix although winter it is genrally recommended that a 50/50 mix is used. You do not have to pre-heat the oil to change the viscosity of the oil as it does not get that cold even in winter, however it is not a good idea to let it stand for long periods without use. At 60p a litre just travelling to work and back using a 50/50 misture will save me at least