Does anyone on here do it? I know that, chemically, it is possible, but how do modern diesel engines handle it? Do adaptations have to be made?

Let’s say that my early noughties Peugeot was sitting on empty in front of my house and I had a large bottle of vegetable oil in my cupboard. Could I actually just go outside, pour it into the tank, and drive off, problem free?

If so, what are the environmental implications?

[Assuming all appropriate declarations to the tax folk are made, of course.]

how do modern diesel engines handle it

They don’t. An older one might though. You need to “do” something with the veg oil first, blend it or treat it somehow.

Did many 1000’s of miles in 2 x 300TDi Landrovers on a mix of Veg oil & Diesel.

The 300TDi is not a modern common rail diesel engine though, and is pretty agricultural.

In the summer you could get away with 50/50, but in the winter i’d stick to <10% vege oil.

The only issue I had was the veg oil rotted through the fuel bleed-off hoses which linked across each injector.
a £2 length of better quality hose from the local motor factors fixed that.

Not sure it is worth it at the moment though – Diesel is probably cheaper than veg oil right now!

You need to “do” something with the veg oil first, blend it or treat it somehow

Only if you want to turn it into biodiesel, which can be used on a wider range of engines.
Regular NEW Veg oil can just be mixed with normal diesel in older engines.

Note – using old/used vege oil is totally different story.

There is loads of info on-line about this..

Common rail diesels can’t do it apparently (though if you read the small print on diesel pumps it can be a certain percentage biodiesel ie veg). Older diesels can do it though, depending on the fuel pump. From memory Bosch and Nippon Denso are best for this.

I used it in both my Hilux’s all the time. 10,000+ miles. I know of a few guys who’e done 100k. Used undiluted in the summer, poured right in the Tesco’s car park 😀

The truck actually ran better on it. I used to dilute it with diesel or petrol during the winter though, just to stop it coagulating.

You need to remove the glycerol from the oil for it to work properly, if you used any quantity of raw oil you’d goose the engine

We’ve got an older Mitsubishi diesel, M reg, and I just pour it in. Normally buy it from Tesco, fill up in the car park and pop the bottles in the recycling. Pretty sure its better for the environment over all but needing the bottles makes it a bit questionable. Doesn’t work so well in the cold so I normally keep it max 50% diesel/veg when it is chilly and it’ll be slow to start. Some people add heaters to avoid this. It blocks the fuel filter quickly the first few times as it picks up gunk from the tank. It also smells like a chip shop. When diesel was £1.50 and oil 80p it was great. Now there is less benefit, £1 to 90p.

environmentally, NOX, worse: SOX better: particulates worse: climate change better – a bit.

Regular NEW Veg oil can just be mixed with normal diesel in older engines

So blending then? 🙂

Depends on the specific car, you should be able to find out.

My old Citroen ZX was supposedly compatible as it had a Bosch fuel pump, but the models with a Lucas pump would die. (or was it the other way round…?)

So just cos it works for someone else, doesn’t mean it’ll work for you…it needs a bit of research.

Common rail, no don’t do it, old biffer agriculture, yes ish. If you want “proper” bio you need to put the oil through a transesterification process. The triglycerides react with an alcohol when a catalyst is added, normally an acid based, this then produces fatty acids. You then have to wash the alcohol away so that you preserve the flash point. Cold flow properties of “proper” bio aren’t tpp bad, but unprocessed and anything below 5C and you’ll struggle.

Anyway, it’s all about Hydro-treated vegetable oil now – similar characteristics to normal hydrocarbon diesel.

I used to love filing my old van with those huge cans of veg that tescos used to sell but at some point veg started costing just as much as diesel.

As has been mentioned modern injected diesel engines don’t like it as much as without heated fuel lines and blending it can clog the injectors.

Loads of info about it out there but I can’t imagine it’s even worth bothering with at the moment with diesel prices being so low.

I used to run a pug 205 1.8 n/a diesel on pure veg oil in the summer. It ran smoother and less clattery on it, but stank. The first few fill ups felt weird, first in in Tesco car park, thereafter on the street. You don’t (or didn’t) have to pay tax on it for personal use up to about 10000 miles a year or something.

At the moment with diesel relatively cheap, it’s not worth the risk Imo… In fact, is more expensive tho run on veg oil. Unless it really doesn’t matter if you kill the car. Veg oil takes all the crap off the inside of fuel lines, the tank etc… You’ll need to replace the fuel filter at least a couple of times early on after you start using veg oil. Then there’s potential damage to seals in components the fuel goes through…

Your call!

cp

In fact, is more expensive tho run on veg oil. Unless it really doesn’t matter if you kill the car. Veg oil takes all the crap off the inside of fuel lines, the tank etc… You’ll need to replace the fuel filter at least a couple of times early on after you start using veg oil. Then there’s potential damage to seals in components the fuel goes through…

Your call!

As a counterpoint to that, I didn’t experience any of the above issues (changed the fuel filter after the first two tanks of veg). After that, I changed/ checked the fuel filter and there was no dirt or detritus. Cleaner than diesel. Same for wear on seals or fuel lines, although this will vary from engine to engine I had zero issues. Some grades of rubber may swell and degrade, but again, no experience of this.

I would have to assume a lot of this methodology (changing filters, damaged fuel lines) comes from people who are recycling chip fat and some degree of this damage is probably due to the solvents they use to clean or dilute the oil….acetone, petrol etc.

At the moment with diesel relatively cheap, it’s not worth the risk Imo..

This would be the caveat to all that though.

We used to run our L reg Toyota Lucida on 50/50 veg oil/diesel and it was fine, but then the price of diesel came down and the price of veg oil went up (about the same time that the gubmint/HMRC decided it was ok to run a diesel on oil I think).

I used to run an R-reg Fiat on a mix of diesel and veg oil, it worked fine (better than pure diesel).

But then gradually the price of veg oil went up (as more and more people started cottoning onto it I think) and then I got rid of the car anyway and the newer common rail diesel simply won’t run on the stuff.

I used to run my Transit on almost pure veg. I kept upping the mixture to see what happened and it ran smoother and quieter and smelled like a chip shop. Did it for 3 years.

Pure rapeseed straight from the bottle when it was 48p a litre. Don’t know the current price is but last time I looked it was over a quid.

These days I wouldn’t want to drive a gutless old agricultural diesel even if it was still cheap.

as per my post in the odd cars I did in both my xantias. The issues was really to do with which mechanical pump was installed in the engine ( bosch v lucas. IIRC Bosch was the one to have ). Common rail engines with electronic wizardry (HDI) didnt like veg oil. I used new oil and mixed it 90% veg / 10% diesel in the summer and more diesel in the winter. The smell was sweet and nothing like chip fat that people say. The car seemed smoother and less tractor like if that could ever be said of a diesel lump.
MIL had a small peugeot that ran with a veg oil mix but all these cars were pre y2k
I toyed with the idea of preheaters for the new car but in reality I may as well make bio fuel if I could source used oil when the price of oil goes back up

When I lived on the Isle of Mull a local used to run his van on the recycled oil from the local hotels etc. He treated it himself, not sure what he did, filtered it maybe? old van, worked well it seems. But yeh, whenever he drove by I would get a massive urge for a bag of chips!!!

Ran my old LDV camper on it ,plus GO GO Juice as we called it which was refined old chip oil,process of filters n old immersion tank to bring it up to 60 degrees .then filtered off .

Customs didn’t like it as mucks up there equip, thou they can’t actually do much about it .best tell em then they wont dip u ,as long as you don’t mix withred or green tax rebated diesel.

Like others I used it for years and thousands of miles in my old merc and toyota van, never worried about treating it, just filtered and mixed 50:50 with normal diesel. I used to get it free from work but these days I can’t be arsed with all the filtering and diesel being cheaper etc. I’m a convert to that posh v power type diesel now, 10p a litre more but van runs much smoother, nippier and better economy so well worth the difference.

Have a nose through here. http://journeytoforever.org/

But yeh, whenever he drove by I would get a massive urge for a bag of chips!!!

😀

LOL!

Probably not worth it now as diesel is cheaper. My old 300TDi landy loved the stuff. 75% in the summer. Quieter as well. It isn’t good for some engine seals and can clog fuel filters etc. A few thousand miles did no harm to mine. Its actually quite sickening to follow a vehicle running on the stuff on a hot day in slow traffic.
Go and look on Difflock.com for some good input from a few years ago.

You’ll find help at autoshite.

as long as you don’t mix withred or green tax rebated diesel.

That’s a new one on me, what’s ‘green diesel’?

different countries add different dye. red diesel in uk, green in ireland, portugal etc

I’m sure you can save by buying in bulk but diesel is currently 97.5p a litre and vegetable oil is 110p a litre. I read a surprisingly interesting thread somewhere about someone who bought a sort of ‘refinery’ for want of a better term from the US for £1000 or so which turned used cooking oil into biodiesel which he collected from local takeaways and such who we’re happy to be rid of it. I believe HMRC allow private individuals to produce quite a bit without paying duty if you don’t sell it.

Ran two VAG n/a 1.9 diesels on straight veg oil, cut 50/50 in winter, didn’t change anything, no bother for 15k a piece. Was £1.40 vs 80p a litre at the time and got the same mpg, so worth the weird looks in tesco car parks.
Not worthwhile at current prices, also harder to find a simple enough Diesel engine now that’s worthwhile

If I recall.. The price of veg oil went up because of people using it as an additive.. Making it hardly worth the effort.

If you have a local takeaway you can filter and refine used veg oil.. Me and a friend looked into setting up a little sideline in doing this a few years back but all our local takeaways seemed to have some sort of deal already.. Too late to market!