I'm not sure how many people here this will be of use to but I'm avoiding finishing off my uni work so thought I'd post it.
If you own a diesel car and it fails it's m.o.t of emmissions then simply run the car on Vegetable oil for a spell and it reduces the emissions.
My dad and I have been experimenting with the whole Biodiesel/fuels thing for a few year now, have tried most of the methods traditional. Making Biodiesel by mixing methanol etc, adding solvents to thin the oil, running dual tanks in the car, single tanks with various heating arrangements and eventually got to a system that was easiest to run such that there hasn't been a need to put diesel in the car for 3 months and then it was time for an m.o.t. The guy at the test center said they had to take the reading twice because it didn't give a reading first time (too low) and when he managed to read something it was lower than he could remember ever seeing.
It's a rather long way of saying burning used oil (10p/litre) is better than Diesel (102p/litre) in yet another respect.
P.S: This is legal in the UK, but if you live abroad check with customs before trying it. Untill recently we had to declare tax on each litre keep records etc, and you may have to do the same (UK law has now changed though)
(Time for some shameless advertising, more about running cars on Veg Oil on my dads website: Beats waiting for the lorry drivers to strike. (//www.southwestbiofuels.co.uk))
I read in my users manual that it voided the car's warranty using bio-diesels... so you may want to think twice about it if your car's under warranty.
PEN
I run a 14 year old Defender 90 200Tdi - Biodiesel here I come!
Quote from: Penfold;214813I read in my users manual that it voided the car's warranty using bio-diesels... so you may want to think twice about it if your car's under warranty.
PEN
If it's new your car may have a Common Rail injection system, which requires the fuel to be a certain thickness etc, that means running vegetable oil might not work (never tried on anything like that). You'd have to go with Biodiesel, which is more tricky to make but have almost the same properties as diesel.
If you're still within warranty on a car the fuel prices are probably less of a concern as you can afford a new car.
As with all things if you do it right you won't have a problem, but if you're making your own biodiesel theres alot to keep in mind. How to get hold of (toxic) Methanol (not as hard as you'd think), which method will you use to make the biodiesel. You'll need to test the pH, it should be neutral to avoid damaging the engine... etc.
Though to be fair on Biodiesel according to the mechanic at the local m.o.t place we used, having a LPG conversion on the car appears to correllate too closely for comfort with extreme engine wear, and that barely saves you any money per mile.
I was mostly bringing the subject to light, rather than suggesting it's right for everyone. (for a start if everyone used it the price of used oil might go up and I don't want that). And my tip for anyone who wants to start is experiment. And my warning for anyone thinking about it is you'll need a lot of space in your garden/garage and ideally own or have a friend with a van/estate car.
(Some Chemistry skills and the ability to build basic pumbing rigs and electrical systems help things run smoothly too)
Ahh do'nt get me wrong - I'm not being critical..... more concerned if someone knacked their warranty because of it.
Anything to save A. money and B. carbon emissions (in that order!) is a pretty good thing in my book :)
PEN