How can I worsen my fuel consumption?

Penguin · Post by **Penguin** » 09 Oct 2009, 10:02

rmunns wrote:Particularly surprised to see that, in UK, diesel now only a penny or so more per litre than unleaded.

I believe the recession has a lot to do with Diesel approaching parity with unleaded again. Refineries have traditionally been set up to extract more petrol than diesel (they can be altered but it is a costly process). There was a higher demand for the diesel than had been traditionally experienced due to the large number of people now buying diesel cars. With the recession there is less usage of diesel and similar fuel oils as there are less lorries delivering and less cargo ships traversing the high seas. I only need to look out of my bedroom window at the number of cargo ships layed up in the bay for evidence of this.

Anyway, thats my tuppence worth.

Post by **Peter.N.** » 09 Oct 2009, 11:04

That certainly could be the case, but I think cargo ships used to use crude oil as fuel, don't know if they still do.

falling-out-with-my-car · Post by **falling-out-with-my-car** » 31 Oct 2009, 15:08

Well I bit the bullet and decided I'm not paying over a pound for diesel anymore, No I didnt get rid of the car, I went online and researched filtering waste vegetable oil, and it works out a heck of a lot cheaper than running on dino diesel. if you can bear the smell of the waste oil.
I'm gonna save an absolute packet, what i dont understand is why more people are not doing this it takes up very little time I guess the recession dictates wether people have the money or not to set the filter system up because it costs about a hundred and fifty quid for filters drums fittings, heating elements, pump and copper pipe.

yesterday i put petrol in my diesel for the first time 10% in the veg oil in the winter to stop the fuel freezing.

I have tried to calculate the cost over and over but I still get the same figure and this ones going to give some of you a heart attack are you sitting down?

even with buying petrol collecting the waste oil and costs of processing (running the heaters at night on timers on economny seven) the cost per litre is

0.245 pence per litre. Disgusting insnt it and its perfectly legal and tax free up to 555 gallons/2500 litres per year. now all ive got to do is find somewhere to go. Driving is at last Fun again, not an expensive comodity.

XantiaMan · Post by **XantiaMan** » 31 Oct 2009, 15:15

Why on earth are you using petrol to cut the veg with in this weather? Its not even cold! You'll risk damage to the pump (it happens, i ran 5% when it was minus 2c outside not 12 c!, and the seals went), you will also lower the cetane rating and fuel economy and performance wont be as good. Think you need to research more!

Xaccers · Post by **Xaccers** » 31 Oct 2009, 15:16

Cut it with diesel if you need to cut it at all in this weather!

Post by **Peter.N.** » 31 Oct 2009, 15:50

I think the reason everyone doesn't do it is the potential cost of repairing the injection pump when it starts leaking. If I were you I would try and pick up a cheap secondhand one as a spare.

Peter

falling-out-with-my-car · Post by **falling-out-with-my-car** » 31 Oct 2009, 21:19

Peter got four spares thanks and the reason for cutting the veg was the nightime temperatures starting the car from cold below 10 degrees C the engine was hunting quite a bit now it doesnt hunt at all.

believe me i have been doing the research and to cut the veg to the same level as the petrol does I would have to use 35% diesel which is a lot less cost effective, car runs fine no probs as yet. I have known people to get leaky pumps in the summer running neat veg oil so it really depends on the pump and what kind of abuse it has had in its life.

I think all nice and cosy in your centrally heated homes you dont realise how cold it gets in the bottom of a valley at night, its freezing.
its 9-15pm at present and its 2 degrees C. need to use the inline heater to.

all these people living in luxury on hills and the coasts where its nice and warm.

if your daft enough to have the pump bolted to a test bench and pay inflated costs to have the pump tested then thats your fault but having all the seals repplaced without the test bed being brought into it comes to around £90 which isnt to bad.(you do have a choice). as for performance its brilliant seems a lot more responsive than it was with straight veg oil acceleration seems to be a lot smoother to could be something to do with the timming.

Post by **CitroJim** » 31 Oct 2009, 21:31

falling-out-with-my-car wrote:having all the seals repplaced without the test bed being brought into it comes to around £90

Or follow MikeT's guide and do the same job yourself for under a tenner

falling-out-with-my-car · Post by **falling-out-with-my-car** » 31 Oct 2009, 21:37

Exactly so what with all the alarmist answers then?

as for lowering the cetane rating of Veg oil by adding petrol I didnt Know it actually had a cetane rating in the beginning 0h well you learn something every day don't you.

surely you can only increase the cetane rating of veg oil by adding cetane to it????

XantiaMan · Post by **XantiaMan** » 31 Oct 2009, 21:54

falling-out-with-my-car wrote:Exactly so what with all the alarmist answers then?

as for lowering the cetane rating of Veg oil by adding petrol I didnt Know it actually had a cetane rating in the beginning 0h well you learn something every day don't you.

surely you can only increase the cetane rating of veg oil by adding cetane to it????

Yes veg oil has a slightly lower cetane rating than diesel. Of course off the shelf it wont have a cetane rating but tests have shown that when used as a fuel, its not quite as good as diesel.

Adding petrol does not add cetane. Petrol is rated differently, using Octane. Adding petrol will lower the Cetane rating of diesel and veg.

Alarmist, possibly, but its no fun having a fuel pump fail if you rely on your car every day for work. Its a fiddly job and it has to be done right, so best avoided.

If your having hunting problems when cold its far more likely to be a glow plug or two dead. Mine had 2 dead and would still start on high % veg mix but was lumpy till warm.

falling-out-with-my-car · Post by **falling-out-with-my-car** » 31 Oct 2009, 22:05

nothing wrong with glow plugs they are fine running diesel. actually Martin drove the car not long ago and started it from cold so he could vouch for that.

cetane ratings for veg oil 35 to 45.
regular dino diesel 45 to 55.

if the cetane rating was to low a diesel engine would have difficulty starting reduced power rough operation , noise & vibration.

all the symptoms My car was displaying before adding petrol to thin the fuel, now shes running beautifully, but to give you all and myself the benefit of the doubt I shall go back and look at the figures again.

Post by **Peter.N.** » 31 Oct 2009, 22:11

Fair enough, you obviously know what you are doing. I used to put petrol in my diesel in the winter many years ago, I'm talking about the '60s, engines were not nearly as easy to start then plus colder winters and waxy fuel gave the sort of problems you are having.

Diesel normally contains more energy than petrol, one of the reasons for the improved fuel figures, so what Xantia man says is quite correct in that it reduces the available power but it also reduces its viscosity helping it to flow better when cold.

falling-out-with-my-car · Post by **falling-out-with-my-car** » 31 Oct 2009, 22:13

peter,

you had me all panic stricken for a moment then, but as they say measure twice and cut once.

falling-out-with-my-car · Post by **falling-out-with-my-car** » 31 Oct 2009, 22:20

i have read some where that not all garages add the necessary lubricants to fuels to keep cost s down so that they can sell it cheaper wether or not there is any thruth in this I don't know because we never show much concern over what is traveling through that nossel we stick in our tank filler pipe.

I actually started a thread on vegetableoildiesel.co.uk to ask about what percentage of petrol to use with refined WVO.
I wouldn't dare go ahead without doing the research first of all but as i said i'm going to go back over the figures and make sure I havent made any mistakes.
if i have i shall add some Boost adative to compensate for the loss of lubricant.
regards Nigel.

Post by **Peter.N.** » 31 Oct 2009, 22:28

Sorry