Petrol in diesel fuel tank - what should I do?
Discussion
I stupidly picked up the wrong fuel hose filling my Merc turbo-diesel this morning. Put in 4.5 litres petrol (65 litre tank) before I realised the mistake. I then topped off the tank with diesel and have driven home approx. 3 miles. What should I do now?
Am I right in thinking the petrol will float on top of the diesel and that the fuel pump will draw reasonably clean diesel from the bottom of the tank as long as there is plenty of fuel?
Will the petrol slowly mix with the diesel or do I need to take the car to have the tank emptied or similar?
If so, would it be OK to drive or do I need a transporter?
The car has 115 thousand miles on the clock so I don't have to worry about invalidating a warranty. I just want the easiest and cheapest solution.
Thanks in advance for any advice.
Am I right in thinking the petrol will float on top of the diesel and that the fuel pump will draw reasonably clean diesel from the bottom of the tank as long as there is plenty of fuel?
Will the petrol slowly mix with the diesel or do I need to take the car to have the tank emptied or similar?
If so, would it be OK to drive or do I need a transporter?
The car has 115 thousand miles on the clock so I don't have to worry about invalidating a warranty. I just want the easiest and cheapest solution.
Thanks in advance for any advice.
mustard said:
just keep the tank fullish for the next few miles as the others have said to help flush it through, its when you do it the other way around you got a serious problem (diesel in a petrol car
)
As I found out when I was 17 - pretty good impression of a grandprix car. And 8 hours hours pumping it out by hand using a spare mechanical fuel pump!
MarkK said:
As I found out when I was 17 - pretty good impression of a grandprix car. And 8 hours hours pumping it out by hand using a spare mechanical fuel pump!
and it'll
your catalyst!The only way to be sure of avoiding damage to the fuel system of your car would have been to drain the fuel tank BEFORE you ran the engine.
The diesel is also used as a lubricating agent within the fuel system,where components are machines to incredibly high levels of accuracy. the film of diesel is the only thing between some of the moving metal surfaces
Petrol has no lubricating properties, so before long the fuel injection pump and the injectors will sieze up or score.
As you've topped up the tank now and driven it home without failure, you should be ok if you keep brimming the tank for the next few days.
The diesel is also used as a lubricating agent within the fuel system,where components are machines to incredibly high levels of accuracy. the film of diesel is the only thing between some of the moving metal surfaces
Petrol has no lubricating properties, so before long the fuel injection pump and the injectors will sieze up or score.
As you've topped up the tank now and driven it home without failure, you should be ok if you keep brimming the tank for the next few days.
My father-in-law did this to a diesel Merc (although he put alot in) and it packed up, he had it repaired by a merc dealer and although he wouldn't say how much it cost it wasn't cheap, however I think a few litres if 'diluted' as much as possible with Diesel shouldn't hurt as I understand some people mix a small amount of petrol with diesel to prevent freezing in cold weather.
As an aside the funny thing about my Father-in-laws case was that this car was his new replacement vehicle, paid for by the insurance, for his new merc that he drove into a 4ft flood and 'knacked' - how much I laughed
As an aside the funny thing about my Father-in-laws case was that this car was his new replacement vehicle, paid for by the insurance, for his new merc that he drove into a 4ft flood and 'knacked' - how much I laughed
yup, years ago the diesel was treated to a splash of petrol to help reduce the waxing of the diesel in cold weather.
unfortunatly the tree huggers of this would saw fit to demand a cleaner diesel and the oil burning public wanted a diesel that was good for all seasons without the need to mix it.
so we waved farewell to the sulphur content and a few other interesting bits and said hello to additives which don't lke petrol so much
A typical Bosch VE fuel pump will cost about 600/700 for an excahnge unit with injectors anywhere from 50-200 each.
new common rail systems won't leave you with much change out of a couple of grand if it all goes pete tong with the choice of fuel
unfortunatly the tree huggers of this would saw fit to demand a cleaner diesel and the oil burning public wanted a diesel that was good for all seasons without the need to mix it.
so we waved farewell to the sulphur content and a few other interesting bits and said hello to additives which don't lke petrol so much
A typical Bosch VE fuel pump will cost about 600/700 for an excahnge unit with injectors anywhere from 50-200 each.
new common rail systems won't leave you with much change out of a couple of grand if it all goes pete tong with the choice of fuel
Firstly how old is the car?
If it is fairly new and uses a common rail high pressure injection system then the damage is already done and irrepairable.
Petrol in diesel is a big no no nowadays. even a tiny amount of water in your diesel will destroy teh very delicate parts of the fuel pump.
You may have been lucky and got away with it. Rule is never drive a Diesel that's had Petrol in it. Always drain te tank fist.
If it is fairly new and uses a common rail high pressure injection system then the damage is already done and irrepairable.
Petrol in diesel is a big no no nowadays. even a tiny amount of water in your diesel will destroy teh very delicate parts of the fuel pump.
You may have been lucky and got away with it. Rule is never drive a Diesel that's had Petrol in it. Always drain te tank fist.
james_j said:
Just brim the tank with diesel and keep it brimmed for the next few hundred miles to dilute the petrol as much as possible. I'm sure a few litres of petrol in a full tank of diesel won't hurt.
Have you got professional liability insurance? Cos you might need it.
Erm Pistons, rebore, bearings, camshafts, injectors, sundries....
lol
Jessica, are you a qualified diesel engineer? Becasue I know from experience that 90% of dealer mechanics have no idea of the damage that can be caused by water/petrol in deisel fuel.
As for the knackered parts in that quantity it should just be the pump and possibly the injectors that will be shot but when you average Mondeo FIP cost £1000 it's an expensive mistake!
Jessica, are you a qualified diesel engineer? Becasue I know from experience that 90% of dealer mechanics have no idea of the damage that can be caused by water/petrol in deisel fuel.
As for the knackered parts in that quantity it should just be the pump and possibly the injectors that will be shot but when you average Mondeo FIP cost £1000 it's an expensive mistake!
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