Tri-Fuel

Has anyone got experience with fitting and running three types of fuel on the same vehicle. I know someone who has a tdi and fitted LPG. He's now considering fitting a third tank for veg oil. I believe he aims to run the diesel with an equal mix of veg oil and introduce a 15-35% mix of LPG. If it works it should be highly economical and great performance. I know how the LPG is governed but how difficult is it to get the diesel and oil to mix proportionately? Is there a preferred veg oil if so where can it be bought in quantity and how much?

Why dont you just put the veg oil in the tank with the diesel, also do you mean veg oil or bio diesel when you say this? Veg oil is not great for the engine.

LPG injection, its common here in the US as it lowers the combustion temp of the diesel and increases horse power. I don't know about doing it with an engine that is set up to run on LPG though?

Hi Everyone, My Name is Wilbur, I am a newbie, hate that word.

Just thought I would reply to this one as I have a good knowledge of running Diesel fuel systems on both B100 and Veg Oil. I am not a chemist but my job involves running allsorts of combustion systems on virtually every type of combustible material, Solid, Liquid or Gas.

About 10 years ago I was in the process of designing a Solid Fuel Dragster (No Joke or Spelling mistake)


Quote ; "Why don’t you just put the veg oil in the tank with the diesel, also do you mean veg oil or bio diesel when you say this? Veg oil is not great for the engine."
I hope I am not teaching anyone how to Suck Eggs?? But Veg Oil IS OK for the engine if a few precautions are taken and you don't go above 10% veg oil to 90% Fossil Diesel in the winter and 25% veg / 75% Fossil in the summer. Oh and pay the C & E Duty on the Veg Oil of course !!!
I will leave it at that for now, and if anyone wants to know any specifics, then they will ask.

And I must add this disclaimer, that it all depends which car you have, what year and even what diesel pump the engine has fitted, so I can't take any responsibility for this info, you will have to satisfy yourself, and like I did, Take a leap of faith.

Anyway, Hi again, and TTFN, Wilbur.

Hi Wilbur - I've got a question for yer re B100...

What's the comparative lubricity between B100 and DERV ?

Cheers in advance mate,

Hi Adz, I'm affraid there isn't a simple answer to that as it all depends on what type of Parent Veg oil its produced from, IE Soy, Canola, Coconut, Palm Oils etc, etc, If you can find out what the stuff you have is made from you may have a chance but as far as I'm aware there is no Standard for lubricity at this moment in time? I know that it has a greater lubricating effect on the pump and injectors we use, actually making them quieter, and has a higher Cetane number (60-70 compared with 51-55 for Fossil) which makes it burn more completely reducing Particulates, Nox and Unburnt carryover, effectivly cleaning the combustion area in the engine, there may be a slight increase in fuel consumption and you do have to watch your rubber and nitrile seals as it contains Oleic and Methyl Esters, these tend to eat the stuff away, so if your pump has any rubber components inside the B100 may affect them, causing damage to the pump, Satisfy yourself of this before putting this through your precious Injector Pump.

I'm sorry I haven't directly answered your question, but hope this Babble helps, TTFN, Wilbur

Heh - certainly has thanks. I didn't need absolutes or statistics just an:

It's better/worse/the same* (*delete as appropriate)

If I've read your reply correctly, the B100 you've been using has lubricated the fuel and injection pumps better than Dino Diesel - which is pretty much what I was hoping.

Thanks,

Many thanks for the advice on mixture rates Wilbur. I believe the most important question was how easy is it to mix the diesel when using two tanks and (yes) I think he's talking about using (Tesco) sunflower cooking oil in one of the tanks. I also think he is installing a heater. To avoid confusion over the LPG he has a 30 litre LPG tank under the sill which supplies gas to a water heated regulator. The gas is fed to the inlet manifold and the turbo/venturi differential pulls it in. The car is a 97 Disco 300tdi so do you think the pump and seals will be ok for veg oil? Got any suggestions on how to regulate the oil/diesel mixture?

Thanks

Wilbur;294383 [COLOR="Red" said:

Quote ; "Why don’t you just put the veg oil in the tank with the diesel, also do you mean veg oil or bio diesel when you say this? Veg oil is not great for the engine."[/COLOR]
I hope I am not teaching anyone how to Suck Eggs?? But Veg Oil IS OK for the engine if a few precautions are taken and you don't go above 10% veg oil to 90% Fossil Diesel in the winter and 25% veg / 75% Fossil in the summer. Oh and pay the C & E Duty on the Veg Oil of course !!!

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A lot of people say veg oil and mean bio diesel, however veg oil is not good for the engine, in smaller quantities it will just take longer to cause the damage from the deposits.

Also bio diesel is closer in viscosity to diesel, raw veg is around 40 to 50 centistrokes where as bio and diesel are all within 3 to 5, raw veg really is too thick, which can lead to injection problems and bad lubrication of the pumps.

The cetane number of raw veg oil is also lower than that of bio and indeed derv, so its not as effective at burning and giving a good combustion process, thus could lead to a loss of efficiency.

Back to the original quesiton, best bet would be simply to make a 50/50 mix of bio/derv, and then have the LPG system.

There is a site on the net somewhere that tells you where all the bio diesel filling stations are, and its cheaper (usually).

Quote "A lot of people say veg oil and mean bio diesel, however veg oil is not good for the engine, in smaller quantities it will just take longer to cause the damage from the deposits."

What ‘Deposits’ are you talking about specifically ???

As a person, I do know my Veg Oil and Bio Diesel Thank you, and although you have to keep your eye on your lube oil as the veg oil tends to pass by the piston rings and get into the sump, causing a rise in lube oil level and a thickening of the lube oil, this happens quite slowly, and you can get sump oil to alleviate this and keep your eye on the level, and as for lubricity there is no problem, as after all we all check our dipstick every week ???? pinch the oil from the bottom of the stick and if it starts to 'String and get Sticky" then its oil change time as it will be blocking your oil filter.

I speak from experience when I say that the 10% veg oil to 90% Fossil Diesel in the winter and 25% veg / 75% Fossil in the summer mixed in ONE tank only raises the Pour rate of the fossil diesel slightly by a few seconds, and in the summer the %age can be raised as the ambient temperature goes up, but if you use it through the Bosch fuel pumps you would be OK, the Lucas type pumps are not as robust so I don't recommend using it through these.

Also, petroleum companies change their fuel chemistry depending on the time of year, so the Fossil Diesel is slightly thinner in the winter anyway, this also happens with Petrol, I believe.

Like I said earlier, you have to take a leap of faith an be prepared to take the consequences if anything does go wrong, and this is not for the feint hearted, as things DO go wrong, but I am all for experimentation, I am not a bottomless pit of money but I do believe this is a good way to go to lower the reliance on Fossil diesel, it may not solve all the problems and the use of NEW Veg Oil will only cause the price to rise eventually, but there are already large companies monopolising the collection of the waste veg oil, so you have to be pretty passionate to go scavenging for this round you local restaurants.

All this said it is down to the individual, and you must be satisfied with your own abilities and be prepared to take a fall or two along the way, I knackered my first fuel pumps relief valve, but it made me learn how to strip a diesel pump as I refuse to pay £1000 for a recon item, and as I work in engineering, I could get stuff made.

I work with Gas Turbines, and they spin at slightly higher speeds than a car engine and a fair bit hotter, so their lube oil has to be spot on, but it is a good job that old Frank Whittle took a few chances with his first engines or I would be on the dole, and the oil companies would still be using Diesel engines to pressurise the oil out of the ground.

Sorry for being such an anorak.

TTFN Wilbur

Well that seems to have answered the question, mix it in the same tank. If it were me I'd follow the advice of buying Bio to play safe. No point in killing it just to see if you can. I am seriously thinking of fitting LPG to my 300tdi since Allisport uprated it last year. It goes really well but now suffers from "right foot can't resist the temptation" syndrome and as you'd expect the economy has dropped. I trust the LPG conversion will add extra icing and improve the cake so I have to ask is it really worth trying to go that bit extra with the TRI-fuel especially if you have to trundle all over the place to save a few quid on the oil and then mess about with blending it?

Many thanks guys, I'll pass on your comments

[quote To avoid confusion over the LPG he has a 30 litre LPG tank under the sill which supplies gas to a water heated regulator. The gas is fed to the inlet manifold and the turbo/venturi differential pulls it in.
[/quote]

Let's get this clear .... the gas is fed in to the INLET side of the turbo, and then sent to the engine?

Send me a copy of the video when it blows up. From the Turbo to the engine, through all those pipes and the intercooler, is a fair volume of propane gas mixed with air, compressed to about 15 psi, and hot from compression. If that ignites because of a small flamer spit-back at an inlet valve, stand by for a BIG BANG!

Since when did the inlet manifold come before the turbo
However in one case I do know a person who does inject the gas immediately after the turbo thus sending it through the intercooler etc. He claims it gives a better mix but I reckon there must be a significant lag in response if not explosive risk
Sorry if my poor explanation baffled you.
The gas after it has been regulated and duly warmed is fed on demand through a hose to a volume mixture control valve and then to piece of tube which is fitted into the inlet manifold. The tube fitted at right angles to the air flow acts as a venturi when the air from the turbo passes it. The depression in the hose causes a diaphram inside the regulator to move and a valve opens proportionally to allow gas back along the same tube. The greater the drop in pressure the higher the gas flow. The diaphram is normally equalised both sides by feeding pressure from just past the turbo. Its the differential in air pressures that operate the gas valve proportionaly.

Unfortunately I don't like this system as in past vehicles it suffered from blowbacks with as you might expect disasterous results.

Going back to the person who injects gas just past the turbo. He actually uses a different method of regulation. His regulator uses the turbo pressure to open the gas valve. The higher the boost then the higher the gas feed.
I prefer this system as it uses positive pressures. The regulator can be adjusted to give the right amount of gas relative to the degree of air input.
However, this system uses a camping gas bottle fitted inside the vehicle. I'm not happy with that and prefer an external tank under the sills. Until the two systems are married up I'm taking my time.

Are you just going to mix your bio/derv in one tank now?

QUOTE: "The gas is fed to the inlet manifold" and "the turbo/venturi differential pulls it in"

discomania said:

Are you just going to mix your bio/derv in one tank now?

Click to expand...

I'm only looking at someone else doing it with veg oil. I can't see the point of all that hassle. I'll do the LPG when I'm convinced it's safe. Where do you find the bio and what does it cost? How do you confirm the mixture ratio in your tank?

Hello Gents,

I have been struggling with the concept of two fuels combined Veg and fossil diesel, let alone considering 3 types I must have been absent from the class when the physics and engineering lessons were on!!

From what I have so far gleamed from the Tinternet is as Wilbur has already submitted for certain diesels a blend/ratio will be fine dependent on fuel pump the lucas/bosch.
As for ratio's it has been suggested in the summer 70/30 diesel/oil and so i'm led to believe Tesco are the cheapest..

The point raised about Bio diesel I would Ideally like to use this however outlets are few and far between... and the processes to make your own is a good prospect but the quality assurance could be problematical as with HM revenue folks....

If I had a title like yours others would expect me to use quad-fuel.
Three for the car and one in my flask

Most bio diesel makers will sell it by the 45gallon drum, or just take a few containers and buy it in bulk if they are far from where you live.

Welcome to Biodiesel Filling Stations lists suppliers in all the different areas.

It will cost you about 85pence a litre, and for every litre of pump diesel you put in, put in whatever you need to make up your ratio. I only ever know roughly what the ratio is in my tank, sometimes I will fling 40litres in on top of 10litres, and drive about on that for a bit until I pass a garage etc and then just fill the tank. Its not really an exact science, its just about getting a sort of mix done for the majority of your driving to keep Lucas pumps happy etc...

Quad fuel another concept for us mere mortals to contemplate....
Although I do enjoy the contents of my hip flask especially when watching the rugby!!!
Maybe the single malt scotch might amend the aromatic smell of Veg oil have we stumbled upon the magic ingredient???

Quick wheres a lawyer when ya need one ..... Which way to the patents office