just what can you run a diesel on?

moomin · Post by **moomin** » 15 Sep 2004, 22:16

i heard from someone that you can run a diesel on just about anything. so i was wondering, whats the difference between the sort of oil used in home central heating, and diesel, basically ive got a load and i want to know if i can run my car off of it.

Stuart McB · Post by **Stuart McB** » 15 Sep 2004, 23:17

Shouldn't let the tax man know your plans. You can bet some where the bugger has an extra tax for people who use invention to save money. Have a site search under cooking oil or simalar. I know there was thread on the Citroen site.

woody-som · Post by **woody-som** » 16 Sep 2004, 00:38

a local garage was talking to me about this a few years ago, as someone turned up to have there car MOT'd, and IIRC the mixture was 9 parts cooking oil, 1 part meths.
not tried this, and can't really be botherd, as you are supposed to inform those nice customs people, so you can pay the duty. not worth the hassle IMHO.

reblack68 · Post by **reblack68** » 16 Sep 2004, 11:32

My mate has a garage and he used to burn all his waste oil in a Cavalier Diesel. All of it, whether it was engine oil, gear oil or even brake fluid. He put a gallon of petrol in with four or five gallons of oil.

JohnD · Post by **JohnD** » 16 Sep 2004, 12:37

Ive been using diesel for more than 25 years and one of my first vehicles was a transit minibus. I ran it for a long time on heating oil which came out of the tank at the back of the garage. Quite illegal, which is why it was red in colour.

Homer · Post by **Homer** » 16 Sep 2004, 23:37

Modern HDi type diesels are more picky about what they will run on but the older types will run on a wide variety of substances.
I once had to do some impromptu servicing on an oil fired central heating boiler and the fuel certainly smelt (and felt) like diesel.

r_306_XSi · Post by **r_306_XSi** » 17 Sep 2004, 02:48

Hi there,
Thought I'd add my tuppence worth!!
I used to work as an R&D Engineer for a Boiler / Combustion company in the south, and you are right - given the right conditions any old oil will burn - we used to burn all sorts of rubbish in big burner / boiler applications - from explosive Naptha to chicken poo!!
However, in a car engine, tolerances are a lot tighter, and the combustion mix cannot vary much before you run into problems with lubrication and "too explosive" explosions hich could put extra stress on pistons/con rods etc
So, especially with newer ECU controlled & HDi style diesels, I would be very wary about putting in anything other than "pukka" diesel - unless you don't mind destroying your engine. If you are considering sticking in some central heating oil / cooking oil mix - make sure you understand the principles and risks involved before just whacking in a load of a.n.other fuel- do a google search, theres lots of links on this subject.
And finally, if you are intent on being a little eco-friendly and using used cooking oil, make sure you strain out the chips / batter / debris!!

bikeboyz · Post by **bikeboyz** » 18 Sep 2004, 00:44

I recall from the last fuel shortage/strikes that a few people got caught running there diesels on cooking oil mixture. It was the smell of chip fat from the exhaust that gave it away!

mote · Post by **mote** » 01 Oct 2004, 05:31

I make biodiesel (legally) so have a little knowlege on the topic.
It depends partly on your fuel pump. The lucas/roto/cav/rotodiesel pumps are known for suddenly failing on cooking oil which we call SVO (straight veg oil) cold starts can be a big problem and most SVO users have heated tanks, fuel filters etc and a dual tank system to start and stop on either petrodiesel or biodiesel. This saves trying to start on cold veg oil which is thick and claggy.
Biodiesel is about twice the viscosity (thickness) of petrodiesel. Virgin (unused for cooking) veg oil is about five or six times the viscosity of petrodiesel. Used oil or WVO (waste veg oil) can be worse and contain tallows (animal fats) from cooking that make it thicker and more viscous. More prone to gel up when it's cold.
If you thin the oil down with white spirit it takes 45% white spirit to equal the viscosity of biodiesel. 5% as advertised by some makes naff all difference although may effect the detonation properties.
Bosch fuel pumps are more tolerant of thick viscous fuel as are mercedes.

Brilec · Post by **Brilec** » 04 Oct 2004, 04:54

Beware, if you use central heating oil, (ignoring the legallity) make sure it is the heavy (35 second) or Gas oil. If it is the light (28 second) oil, it will knacker your pump in no time as the pump relies on the lubrication given by the heavier fuel.

mote · Post by **mote** » 05 Oct 2004, 00:20

Adding 5% virgin vegoil will help with lubrication.