Converting to use BIODIESEL

Converting to use BIODIESEL

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Discussion

dotdog

Original Poster:

457 posts

222 months

Tuesday 19th February 2008
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HI - I run a Fiat Doblo Cargo with the 1.3 multijet, do a lot of miles, and can get Biodiesel at Enfuels in Thatcham at 96p/litre, which would make a significant saving, considering I'm doing more than 1000 miles a week.
Does anyone run bio in this vehicle - I know the fuel filter needs changing after 3 tankfulls then twice as often as usual, and that the breather pipes must be plasti/metal rather than rubber - fiat themselves haven't been too helful, so any advice appreciated

gazoline

13 posts

197 months

Tuesday 19th February 2008
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.96p/litre is a bit steep mate i'm lazy and pay 89.9, but u should at 1000 miles a week look into making ur own. Kit costs about a grand just need a good supply of used oil. Plus there is no tax to pay on ur first (i thinks its) 2500 litres. All in costs about .30p/litre.I will get around to it because i'd save even on my 10000 miles/year. If u beat me to it let me know how it goes.ps i did not bother to check if my 98 tranny had rubber pipes or not guess it doesn't but i did find the bio doesn't like cold starts.Sorry I know nothing about ur chariot of choice.

dotdog

Original Poster:

457 posts

222 months

Tuesday 19th February 2008
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ta- will research some more..

GavinPearson

5,715 posts

253 months

Wednesday 20th February 2008
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Just be aware that biodiesel will affect engine longevity as it finds it's way into the engine oil which in turn breaks down and gums up the internals.

Bear in mind that oil change intervals are determined by oil analysis based on the engine's ability to cope with fuel entering oil via the bore / ring pack interface. Normal diesel has very predictable effects, but fuel made from oil seed / chip fat / other biosubstances can really affect the ability to lubricate once it sees heat in bearings and turbos. And the effect on coping with cam loads is not particularly well understood when the oil breaks down.

You could save money on fuel bills and pay for it at the engine remanufacturer.

My advice is steer clear of biodiesel.

Jack_and_MLE

621 posts

241 months

Thursday 21st February 2008
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Gavin

You are a bit of a prophet of doom.

My younger brother has been running a diesel ZX for the past 5 year and a Xantia before that on dual tank system and he only use recycled oil.

The gumming of the engine only happens if you use vegi oil when the engine is working at very little load and when it is not hot.

Bio-diesel is something new so a lot of people are scared of it. I have been using it in my Audi.
I have stopped using because in winter it tends to be less liquid then fossil diesel.

Bio-diesel and vegi oil is totally different "fuels". Biodiesel is diesel made from vegetable oil often recycled, vegi oil is what you use in your chip pan.

Jack

Jack

Edited by Jack_and_MLE on Thursday 21st February 21:40

GavinPearson

5,715 posts

253 months

Thursday 21st February 2008
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My experience comes from being a Diesel Engine Engineer looking at the effects on a large population of vehicles and reviewing the data with other experts.

Your experience is useful, but is but one datapoint of many to be considered. You probably don't have the benefit of OEM quality engine oil analysis from which to make a judgement.

Biodiesel as sold commercially has a lot of effects that are less than fully researched that can affect engine durability.

That is why I'd stick with normal diesel - it is a known quantity and it doesn't invalidate warranty.

gazoline

13 posts

197 months

Sunday 24th February 2008
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I'am not an engineer but some FACTS about biodiesel might help, biodiesel is better for the engine than normal diesel because it has a slightly higher cetane rating (diesels equivalent of petrol's octane rating) and so contains more oxygen meaning it burns more cleanly.This also means less soot and due to biodiesels greater lubricity in theory should make your engine last longer. All facts some manufactures would rather we did not know, if you have a VAG Group pumpe duse engine it will take 100% bio out of the box for other vag models look for the '2GO' sticker in the handbook.Down side of bio is you will use more of it under load and another point just to confuse even more forecourt biodiesel is only a blend 5% bio yes 5% and 95% mineral diesel the reduced price is due to less tax to make our spin doctor government look green.For anyone looking to make your own bio a few w's to help.www.greenfuels.co.uk , www.jcfuels.co.uk , www.bio-power.co.uk .


Personally I do it just so the government don't get the tax.

Edited by gazoline on Sunday 24th February 15:04

GavinPearson

5,715 posts

253 months

Monday 25th February 2008
quotequote all
gazoline said:
I'am not an engineer but some FACTS about biodiesel might help, biodiesel is better for the engine than normal diesel because it has a slightly higher cetane rating (diesels equivalent of petrol's octane rating) and so contains more oxygen meaning it burns more cleanly.This also means less soot and due to biodiesels greater lubricity in theory should make your engine last longer. All facts some manufactures would rather we did not know, if you have a VAG Group pumpe duse engine it will take 100% bio out of the box for other vag models look for the '2GO' sticker in the handbook.Down side of bio is you will use more of it under load and another point just to confuse even more forecourt biodiesel is only a blend 5% bio yes 5% and 95% mineral diesel the reduced price is due to less tax to make our spin doctor government look green.
The problem with biodiesel is that it is a catch all term for a variety of fuels with some bio-content that vary wildly in quality. The example you gave is generally classified B5, and is generally accepted by the vehicle industry as acceptable to use in modern common rail diesels. This is based on the pump manufacturer having done sufficient testing to show that if a vehicle was run on B5 for it's working life, it could still last as long as a pump run on standard diesel. If the price of this fuel is noticeably lower, then use it.

Then there is the case of B10, B20 and anything else up to B100. Where a reputable manufacturer prepares the blend there are a number of pros and cons. Lower soot production does seem to be a benefit and this reduces the need to go into regeneration on cars / trucks with particle filters. That is good. But on the cons side the speed of degradation of fuel sitting in the tank (storage) seems to be far poorer with high algae growth, whether this is the tank in the ground or on the vehicle, also the fuel is more susceptible to gel in the cold, though the temperatures at which this becomes a problem are generally not seen in the UK.

The other issue is what happens when engine oil is diluted by fuel - a function of normal operation and regenerations on vehicles with DPFs. The issue is that the fuel is not as stable as engine oil and can coke / sludge when subjected to extremes of heat, such as a turbo. Now with B5, this won't be to much of an issue, with B20, B100 and anything in between the results would possibly be detrimental to longevity (which I have seen). It is analagous to taking an engine known to benefit from synthetic oils and then running the cheapest oil you can find. Short term the engine shows no damage and you wonder why you are paying a fortune for your favourite synthetic, until you realise that the engine hasn't really aged. Same deal for biodiesel.

Then there is the deal with people making their own fuel. The attraction of free chip oil powering your car is very attractive but bear in mind that it needs to be properly filtered (5 micron filter is necessary) and blended with the normal diesel to mitigate starting problems. The issues of oil degradation still apply though, and I would generally halve the change time - i.e. a 7500 mile change now should be done at 3750 miles.

As far as the VAG recommendation / acceptance that B100 can be used, it may well be that they feel that they can allow this and have their engine live just through the warranty period. Just bear in mind that after that the owner is on their own. I'd personally avoid B100, but as you can guess I'm a pretty cautious person in this regard.

dotdog

Original Poster:

457 posts

222 months

Monday 25th February 2008
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Thanks all - some intelligent info here..

annodomini2

6,877 posts

253 months

Monday 25th February 2008
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I agree interesting,

What is the opinion on the so called 'conversion' kits, which heat the biodiesel during running (using the coolant or exhaust heat I think) and then flush the fuel system with mineral diesel when you stop?

gazoline

13 posts

197 months

Monday 25th February 2008
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Gavin I'am not trying to dismiss your concerns about using biofuels in any form (B5,B10,B20 or B100)but there are counties like brazil who use only biodiesel and bioethanol instead of petrol and diesel because of economic pressure they can't afford world fuel prices.All major manufactures set thier cars up for these fuels ford,vw etc in that country.The main problem seems to be after some reseach the diesel injection pump or injection systems ability to handle different grades or blends of fuels.All engines can run on biodeisel and for petrol bioethanol the question is can your fuel pump/injection system cope. Check www.deiselbob.co.uk for help.

GavinPearson

5,715 posts

253 months

Monday 25th February 2008
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gazoline said:
Gavin I'am not trying to dismiss your concerns about using biofuels in any form (B5,B10,B20 or B100)but there are counties like brazil who use only biodiesel and bioethanol instead of petrol and diesel because of economic pressure they can't afford world fuel prices.All major manufactures set thier cars up for these fuels ford,vw etc in that country.The main problem seems to be after some reseach the diesel injection pump or injection systems ability to handle different grades or blends of fuels.All engines can run on biodeisel and for petrol bioethanol the question is can your fuel pump/injection system cope. Check www.deiselbob.co.uk for help.
I understand the point you are making but you are not necessarily comparing apples with apples as the emmission control (or lack of them) technologies are different between US, EU, South America etc. And the oil change habits are vastly different.

My Explorer ran very well on E85 biofuel so I am not against biofuels. But I also know that the alcohol evaporates off the oil and gets consumed by the pcv system when it enters via the bores and so it isn't an issue for longevity.

For diesels the pump / injection system is only part of the question.
The other part is do the engines wear out faster when biodiesel gets in the oil? So far I have seen evidence that suggests it isn't that great an idea.

Ignore at your own risk.

EwenMc

5 posts

188 months

Saturday 4th October 2008
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So, running on 100% Biodiesel wouldn't be a problem if you changed your oil more frequently, used 50:50 in winter and checked the fuel filter after starting to use it?

dotdog

Original Poster:

457 posts

222 months

Saturday 4th October 2008
quotequote all
For yuor interest - put half a tank of bio in - mpg on trip computer dropped from 50.2 av to 44.6 av!
and less crisp throttle response - took a couple of tankfuls of shell vpower diesel to restore to normal running...

GavinPearson

5,715 posts

253 months

Saturday 4th October 2008
quotequote all
EwenMc said:
So, running on 100% Biodiesel wouldn't be a problem if you changed your oil more frequently, used 50:50 in winter and checked the fuel filter after starting to use it?
It all depends.....

On how often the oil is going to be changed.

On whether the 50% normal diesel contains enough anti-gel additive to overcome all the problems with the biofuel.

And what you mean by check the filter. It really needs to be replace (and more regularly).

wildoliver

8,821 posts

218 months

Saturday 4th October 2008
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I suggest you listen (if not agree) to Gavin, my family are all in lubrication engineering mainly with relation to bus engines, lubrication and fuel are inextricably linked on Diesel engines, I'm not anti Biofuels at all (cheapness based) but you must be aware of the pitfalls, I wouldn't hesitate to use any of the options (from veg oil to pump bio-diesel) in a cheap old banger, but in an expensive modern car/van/lorry with warranty I would want more assurance than a few guys on pistonheads!

EwenMc

5 posts

188 months

Saturday 4th October 2008
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Well I'm listening to you all. It just seems to me that some people are answering the question "What do you need to do to run on biodiesel?" and others are posting "Reasons to avoid biodiesel." 8-)

It would be good if manufacturers offered more advice but they don't. Anything more than a timid 5% biodiesel mix and they act as though their precious delicate engines will drop dead immediately. So we turn to other sources of information like PistonHeads...

So, does biodiesel cause insurmountable problems for modern diesel engines? I haven't heard of any show-stopping issues. Then again, it's not a simple matter of just filling up with reprocessed chip fat either. I've given it a go with my Grande Punto (1.3 Multijet engine). It runs fine. The fuel filter wasn't affected last time it was checked. More frequent oil changes sound like an intelligent tip. Thanks. The performance fell off slightly after a while but I'm not a competitive driver ;-) and a tank of regular diesel put it right. Given that people will use biodiesel, what would you recommend?


gmtech

10 posts

188 months

Tuesday 14th October 2008
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Hi there

I know the engine and I would not advice to use any other fuel then the prescribed one, injector and pump damage is likely to occur and will be very costly.

GMTECH

EwenMc

5 posts

188 months

Thursday 16th October 2008
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Thanks, gmtech: Very interesting!

What would cause the damage? Is there any way of mitigating it?

ELAN+2

2,232 posts

234 months

Sunday 9th November 2008
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According to Bosch, PD engines are not biodiesel tolerant, its down to viscosity, in that bio has longer molecule chains and the design of the injectors (5 micron fuel filtration in the injector body) and the injector and lift pumps need the lubrication properties of regular diesel. They will however tolerate the blended bio/fossil fuel thats for sale currently...... I've used veg oil in an old volvo without problems, infact quite the reverse, however modern high pressure systems (common rail and PD) are a different kettle of fish.