Biodiesel

cb7

Can all diesel car run on this? I have a 2012 opel insignia can I put into my car and it will not cause problems?

George Dalton

Most. Certainly. Not.

Markcheese

Some vehicles can run on straight vegetable oil,some can be modified to ... others not at all ... Have seen a biodiesel pump at a filling station (few years back) but dunno was that straight veg oil , or had been altered or refined to run in most diesels...

corkgsxr

Isn't it much more acidic too?

dgt

Guess which pump ran on biodiesel.....

Chimaera

It's worth pointing out what biodiesel actually is here, as there seems to be the usual confusion around veg oil and biodiesel.

Biodiesel is technically referred to as Fatty Acid Methyl Ester. It's produced in a chemical process called transesterification that breaks down the triglyceride molecules in vegetable oil and results in a fuel that is relatively close in most of its properties to mineral diesel. It is more viscous, and has a lower calorific value. It tends to have higher lubricity and cetane. Cold weather properties depend on the vegetable oil used to produce it, but tend to be inferior to those of mineral diesel. Rapeseed oil based biodiesel has the best cold weather properties.

It's possible to make your own biodiesel from virgin vegetable oil. With a little practice you can produce a pretty good fuel. Biodiesel can also be produced from waste vegetable oil but it's a more involved process and it's harder to get it right. This is best left to commercial producers. Poorly produced biodiesel can contain high levels of water and methanol which will damage any fuel system.

Biodiesel is NOT vegetable oil.

When it comes to putting this stuff in cars it's a little nuanced.

Modern high pressure fuel systems are carefully calibrated to EN 590 diesel and won't tolerate anything else. So even EN 14214 FAME won't work properly in them. This means anything with common rail or PD injection is not suitable for fuels with high percentages of biodiesel.

Lower pressure systems (either DI or IDI) can handle biodiesel pretty well once the weather co-operates. Anything with a rotary injection pump (Bosch VE, etc) will work ok here. A word of caution: biodiesel is an excellent solvent, so older cars with EPDM rubber tubing in the fuel system will have problems with hoses being eaten away. You'll need to swap them out for Viton tubing. Also, if you switch to biodiesel in an older car, be prepared to change a lot of fuel filters in the first few thousand km as the biodiesel loosens up the gunk that's lodged in the fuel tank and low pressure lines over the years.

Vegetable oil is another story altogether. It's really only suitable for old IDI engines. It's much too viscous for the fuel system to handle properly in the normal run of things. There are conversion kits out there which heat up the oil and these work well enough for older cars. The better ones operate a separate fuel tank for oil and diesel, and use diesel for startup and shutdown. There are some who will claim you can use waste vegetable oil like this. It's really not a good idea unless you've a huge amount of free time to clean up the oil before using it. It works fairly ok with virgin oil. Another option for veg oil is blending it with mineral diesel and this can work ok up to about 50/50 without spending money on a conversion kit. But the bottom line with veg oil is it's not ok in any DI engine.

Chimaera

dgt wrote: »

Guess which pump ran on biodiesel.....

I'm guessing the bottom one got run on waste veg oil judging from the state of it.

Markcheese

Thanks for that... I know of someone who was chucking supermarket veg oil,into the tank of her old transit , around 50/50 with diesel ... She reckoned it was grand, but I dunno how long it lasted,
Also remember seeing top gear where they got clean veg oil ,added 2 or 3 % white spirit and left it sit a couple of weeks then ran an old Volvo on that, don't think they did a long term review though..
http://m.youtube.com/watch?v=GOFbsaNeZps

dgt

Chimaera wrote: »

I'm guessing the bottom one got run on waste veg oil judging from the state of it.

Remember a few years ago there were signs dotted here and there for "biodiesel", usually in a farmyard and usually a good bit cheaper than diesel?

The fella who had that car before me ran his car on it for a good while. I think it was a tanker that collected WVO and mixed it themselves to make their own biodiesel.

Last one near me was in Slane, which stopped selling biodiesel in late 2012

ianobrien

OP, not being rude or anything but what does the owners manual say? Also, is there any notice inside the fuel filler flap? My yoke has a notice there with fairly big writing "No Biodiesel".

Cleveland Hot Pocket

Depends on the car tbh. I've chucked veg oil into a couple of '90s straight diesel yokes running up to an 80:20 (summer) 50:50 (winter) mix and it's grand. Not wvo mind, store bought veg oil only.

On a newer diesel, particularly common rail, not only must you not use vegol, there's usually plenty of warning not to use biodiesel. I know my old 2010 Skoda Superb TDI had this on the inside of the filler flap.