Petrol in Diesel Engine

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Can I expect any bad effects from adding (accidentally) approx 10% (6 litres in 60) unleaded petrol to a diesel engine car. The car appears to run OK at present. Will the two fuels have mixed.
Please keep (deserved) abuse to a minimum and answers to a maximum!
TIA
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I believe they are different densities and the unleaded will sit on top of the diesel like salad dressing. I might be better to drain off the tank before the diesel runs out and you start to get unleaded into your engine. As the level of diesel gets lower the sloshing about will cause some of it to be drawn into the engine and it will start chugging.
I might well be wrong but the unleaded doesn't burn until the compressed and hot diesel ignites thus causing a kick when the unleaded ignites. Another possibly wrong fact is that putting diesel in an unleaded car is worse as the diesel sinks to the bottom guts sucked into the engine and fails to ignite thus filling up the cylinders.
Cheers
Jonathan
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Do not be tempted to add mustard...
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Taken from the AA Web Site:
7. Fuel problems Empty fuel tanks cost AA patrols a lot of time and members unnecessary inconvenience. Fill up at the start of your journey. Every year more than 100,000 motorists put the wrong fuel in their car - petrol in diesel engines or vice versa. In these cases the car will have to be recovered to a garage and draining the tank and disposing of contaminated fuel is expensive.
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On Wed, 13 Aug 2003 08:57:59 GMT, BigWallop wrote:

I guess it depends on how much petrol you put into your diesel tank. A few litres in an empty tank then filled with diesel isn't going to be a problem but a tank diesel tank filled with petrol is another story.
Probably quite hard these days to fill a petrol tank with diesel as the diesel nozzle is bigger than the unleaded petrol hole.
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MartinC wrote:

They will mix just fine, and it will have no adverse effects on your car (it's a diesel, how much worse can it get anyway??).
--
Grunff


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Grunff wrote:

Wasn't adding a small amount of petrol to diesel a trick used in very cold weather anyway?
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Yes - this is a perennial problem which appears on NGs from time to time. Petrol into diesel is not usually a problem. I can't remember the percentage but I have at least one car manual which recommends mixing petrol in with diesel in cold winters to prevent waxing. And it doesn't clog the carburettor or foul the plugs :-)
As stated elsewhere diesel into petrol is a whole different ball game!
Cheers Dave R
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Exactly...it can't possibly clog it up...
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Doesn't diesel compress to ignite??? Petrol on the other hand needs to be lit ... usually with a spark plug unless you live in Sauwf Landon mate ;o)
a
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Yes, and as long as it still continues to do this the resultant explosion will burn off the petrol in the mix. The compression ratio used must be 'over' by some tolerance as otherwise you never get it to start (even with the pre-heaters). I am however suprised that a 10% petrol mix will still work but if others think it will then OK.

Which it will be by the exploding diesel.

Tim
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Yes, as it lowers he temperature at which diesel stops being liquid like.
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Hmm..gullible and unscientific, it seems :-)
As your 10% petrol in diesel is unlikely to cause you any problems, use at least half the tank, preferably at least 2/3 before refilling. This will ensure you remove most of the petrol quickly then go to almost 100% diesel.
i.e. [Assume that the tank hold 100 'units' of fuel] Full tank of 90 units diesel 10 units petrol Use 90% of the tank Tank has 9 units diesel and one unit petrol Fill up with 90 units diesel Full tank with 99 units diesel and one unit petrol (effetively pure diesel).
This after using 90 units of fuel and only one visit to the fuel station.
---------------------------------------------------------------------------- -------
Gridingly boring worked example:
Full tank of 90 units diesel 10 units petrol
Use 10% of the tank Tank has 81 units of diesel and 9 units of petrol Fill up with 10 units of diesel Tank has 91 units of diesel and 9 units of petrol
Use 10% of the tank Tank has 81.9 units of diesel 8.1 units of petrol. Fill up with 10 units of diesel Tank has 91.9 units of diesel and 8.1 units of petrol after using 20 units of fuel.
Compared to
Full tank of 90 units diesel 10 units petrol
Use 20% of the tank Tank has 72 units of diesel and 8 units of petrol. Fill up with 20 units of diesel Tank has 92 units of diesel and 8 units of petrol after using 20 units of fuel.
So already a small difference is showing in favour of using bigger amounts of fuel before filling up.
So long since I did any maths I can't face working out a formula but suffice it to say that it is more effective to use as much of the 10% mix as possible before refilling your tank.
Someone out there must know the formula!
Damn I must find some motivation to work!
Cheers Dave R
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I thought this too until I actually tried one. Take a Golf 130 TDi, Megane 120 DCi or Focus 115 TDCi for a spin and eat your words!
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And that's why they are good for tractors, and nothing else.

I had two turbo diesels and was glad to get back to a real car.

I know. Awful isn't it. All that pollution: black soot they spew out (cacogenic) and the noise. They should be banned forthwith.
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IMM wrote:

Damn - this is worrying - I suddenly find myself in full agreement with IMM...
What shall I do? ;-)
Ah! I know - New Liebour is the party of (screwing) small business - ah that's better feel ok now!
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Cheers,

John.

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Look to the heaven as you are now enlightened.
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harrogate wrote:

Ther are all sorts of diesels, and all sorts of petrol engines. Eiether can be made torquey, revvy, narrow or wide power band.
Diesel is more effeiceint at part throttle mainly tgho modern injection has made petrol very good, and its also more BTU per liter in terms of energy.
The engines are heavier, and tend to spew out carbon at full throtttle, where a diesel is least efficient.
I think the emissions are extremely nasty, and would buy a cat diesel if I could.
You pays yer money. I drive both.Ther isn't ultimately a huge amount of difference performance wise in a decent engine between them.
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Megane
a
not
easily
at
microseconds!
to go

move
puts
more -

A diesel does not have a throttle, it is full air all the time.
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IMM wrote:

It is conventional to refer to any speed reduction system on an IC engine as a throttle.

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