Technical Fuel economy (again, sorry)

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Technical Fuel economy (again, sorry)

Lynt

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Oct 24, 2007
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I seem to be doing about 530/ish miles on a full tank of diesel. I haven't quite got the nerve to let the fuel go right to the wire, so fill up when it is about halfway on the red section, (with yellow light on). (1.9jtd)

Anyway, is that good/bad/ok?
It cost me £54 to fill up today!!!!!!!! (£1.09 a litre)

Just been quoted £520 for 1000 lites of domestic heating oil!!!!!!!!

:(:(:(
 
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Just been quoted £520 for 1000 lites of domestic heating oil!!!!!!!!

:(:(:(

we used to have oil heating and switched to gas...wish we hadn't :(
Once the oil delivery driver was asking if my car was a Diesel and then started sort of hinting that my car would run on the oil. Never tried it but I had an old knackered Pug Diesel at the time so I should have done.

Do you know if Diesels will run on domestic heating oil? Is it the same as red Diesel?
It might be worth a go at about 50p a litre
 
I think I found my own answer by doing some googling

it's called 35 second burning oil and is used in old boilers.
Here's a quote from Goff petroleum:

"Gas Oil is the fuel favoured by farmers, for use in their tractors and by commercial customers for generators and industrial heating. It is still used by some domestic customers, running older boilers, but the majority of older boilers have now been converted to burn Kerosene. Gas Oil burns slightly hotter and so can be more efficient as a heat source. However it carries government duty, and thus is always more expensive to burn than kerosene. Commonly Gas Oil is also known as Red, Agricultural, or Marine Diesel. Gas Oil is 35 second burning oil. It is a Criminal Offence to use Gas Oil as a road fuel."
 
I seem to be doing about 530/ish miles on a full tank of diesel.

is that good/bad/ok?

Sounds about right to me. Mrs_G's JTD can go this far if necessary on 1 tankful however we usually refill before then.

You don't need to run the fuel tank so low to get an idea of you Doblo's average mpg. Do a 'brim to brim' test and you'll get a good idea of how much you're getting to the gallon.

1. Fill right up and reset trip meter.
2. Drive until you need to fill up again.
3. Fill right up again (perferably at the same pump as before - the car will be at the same angle and will fill to the same level).
4. Do some simple maths.

[Miles between fill ups] divided by [litres put in at 2nd fill] multiply by 4.546 = mpg.

Hope this helps.
 
I think I found my own answer by doing some googling

it's called 35 second burning oil and is used in old boilers.
Here's a quote from Goff petroleum:

"Gas Oil is the fuel favoured by farmers, for use in their tractors and by commercial customers for generators and industrial heating. It is still used by some domestic customers, running older boilers, but the majority of older boilers have now been converted to burn Kerosene. Gas Oil burns slightly hotter and so can be more efficient as a heat source. However it carries government duty, and thus is always more expensive to burn than kerosene. Commonly Gas Oil is also known as Red, Agricultural, or Marine Diesel. Gas Oil is 35 second burning oil. It is a Criminal Offence to use Gas Oil as a road fuel."


My friendly local mechanic, who also doubles up as a farmer, bought 1000 lites of red diesel yesterday, and it cost him £400. I paid less than that for 1000 lites of heating oil in July.
The world's gone mad. :(
 
Sounds about right to me. Mrs_G's JTD can go this far if necessary on 1 tankful however we usually refill before then.

You don't need to run the fuel tank so low to get an idea of you Doblo's average mpg. Do a 'brim to brim' test and you'll get a good idea of how much you're getting to the gallon.

1. Fill right up and reset trip meter.
2. Drive until you need to fill up again.
3. Fill right up again (perferably at the same pump as before - the car will be at the same angle and will fill to the same level).
4. Do some simple maths.

[Miles between fill ups] divided by [litres put in at 2nd fill] multiply by 4.546 = mpg.

Hope this helps.

Thanks Niall. I'll (try) to give it a go next time.

Lyn
 
I've got the 1.9jtd 105hp with about 15k on the clock.
I'm getting 400 - 450 miles (depending on the journeys, 450 involves a few longish runs down the nearby dual carriageway, 400 is all around town, loads of short journeys (3 miles)) out of a tank. That's filled to the brim and needle halfway down the red mark. I get 25miles per mark on the fuel guage. Strange thing is, I always fill to the brim as soon as is convenient after 400 miles, the needle is always somewhere in the red zone & I've not yet managed to squeeze in more than 48 litres.
The annoying thing is, the yellow light comes on before the needle hits the red zone & I reckon I could easily do another 100 before the engine coughs (although I don't want to prove it) as the trip is generally on about 350 miles.
There are rumours that I should get higher mpg when the engine slackens off at 20k - can't wait.

OH yes, and the other week, some idiot had parked so he was blocking the road. I tooted the horn a few times & he eventually returned to his car - then sat there. In my anger, I revved the engine harshly quite a few times - didn't do my economy any good, I reckon it cost me a good few miles.
 
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I read somewhere in the handbook(I think) about the amount of fuel left in the tank, when the yellow light comes on, but I can't find it.

I find that light quite unnerving. I can hear it saying "if you don't fill up NOW you will be in real trouble!"

Lyn
 
I read somewhere in the handbook(I think) about the amount of fuel left in the tank, when the yellow light comes on, but I can't find it.

I find that light quite unnerving. I can hear it saying "if you don't fill up NOW you will be in real trouble!"

Lyn

My light comes on way before the red zone, the red zone covers at least a quarter of the guage so I'm looking at somewhere between 100 - 130 miles before the tank is dry?
I agree that the light is unnerving.
The fuel guage is fine as a general guide to what's left but I'm wondering why manufacturers don't use flow meters - wouldn't they be more accurate?
Combined with an onboard computer a flow meter on the filler tube registers how much fuel goes in, a meter in line registers how much goes out & the dash shows the remaining?

(or am I being too naive here?)
 
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If you look at your trip computer it will tell you how long you have left in your tank and will go blank when you have about 40 miles left before you run out i have drove my van for over 30 miles after it goes blank and then filled up but it cost me over 60 quid to fill at 106.9 per lt.
:bang::bang::bang:
 
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I looked at the trip computer when I first got the dobbin but I felt the 'miles left 'till refill' readout was too erratic, it jumped about too much for my liking so I simply look at how many miles I've done compared to where the needle is.
As I've said previously, around town I get 25 miles per mark, so generally fill up around 400 miles.
What I really want is a nice long run to see what I can get from the tank on mainly motorway - but that's not going to happen too soon.:(
 
I don't take any notice of the trip that tells you how many miles before refilling. One minute it says 300 miles and the next 50 miles! So not helpful at all.

I know this is going to be another silly question :rolleyes: so bear with me, but, can you fill a can with diesel, so you have something in case you run out? I've obviously done it with petrol over the years.

Lyn (who doesn't know anything about anything :( )
 
can you fill a can with diesel, so you have something in case you run out? I've obviously done it with petrol over the years.

Lyn (who doesn't know anything about anything :( )

You sure can. I always carry a 10 litre jerry can in my van. Just make sure you have the necessary spout to get it into the van from the can. Diesel is a horrible substance once you spill it. Petrol evaporates off quite quickly but diesel seems to linger forever. I'd be tempted to keep a strong plastic bag to hand to put the fuel can and spout into after use. A pair of gloves from a petrol station would be handy too.
 
did that once.. :bang:

before the engine cut itself off, with all the dash lighting up..
losing power steering,
the engine will start to lose power slightly for a few time first.


pour diesel into the tank.

switch the ign into mar,
let the fuel pump in the tank does it's work.
the fuel pump should run for a few second,
repeat a few time
before starting the engine.

i once read that because of the additional pump in the tank,
doblo need not worry abt airlock,

(y)
 
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did that once.. :bang:

before the engine cut itself off, with all the dash lighting up..
losing power steering,
the engine will start to lose power slightly for a few time first.


pour diesel into the tank.

switch the ign into mar,
let the fuel pump in the tank does it's work.
the fuel pump should run for a few second,
repeat a few time
before starting the engine.

i once read that because of the additional pump in the tank,
doblo need not worry abt airlock,

(y)

Worth remembering. Cheers (y)
 
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