Wrong fuel

aardvaak

OH made a mistake and put about 5 litres unleaded in her diesel the garage attentant said it should be ok if as the tank was nearly full - it was - it is running ok so is this ok?

bod1467

In a typical 50 litre (or so) tank, 5 litres of the wrong fuel (approx 10%) should disperse quite well and not cause a problem ... you shouldn't need to drain the tank and flush the system.

dannyrst

I'd say it depends on whether you want to risk it. As above, it should disperse and shouldn't cause any problems. But that isn't a guarantee.

aardvaak

bod1467 wrote: »

In a typical 50 litre (or so) tank, 5 litres of the wrong fuel (approx 10%) should disperse quite well and not cause a problem ... you shouldn't need to drain the tank and flush the system.

Thank you the tank is a 60 litre tank - Toyota Rav4 and was very nearly full right up - still just about on the full mark.

She asked people at work and someone had done simular thing putting much more in an emptier tank and was told just keep topping up so it does'nt get low for now - it is going ok

Someone else said it is worse if you put diesel in an unleaded car.

jbainbridge

Agree ... it'll be fine. Just keep topping it up as has been said.

Ebe_Scrooge

aardvaak wrote: »

Someone else said it is worse if you put diesel in an unleaded car.

That's wrong. Put diesel into a petrol car, it'll just conk out and no major damage will be done.


Petrol in a diesel car is a different matter. The diesel fuel, as well as being a fuel, is a lubricant, and things like the injector pump rely on the diesel to lubricate it. Petrol is an excellent de-greaser ( not recommended, but I often use a bit in a jam jar to clean up oily bolts etc., before refitting them, it's brilliant at shifting oil and grease ). So what happens is that the injector pump ends up being not lubricated and seizes up, and it's not a cheap thing to replace. And what makes it worse is that the engine will actually run ( albeit rather roughly ) for quite a while on petrol, certainly long enough for things to get damaged.


However - a small amount of petrol mixed in with diesel is not the end of the world. Indeed, in the olden days it was common practice to mix a bit of petrol in during the winter, to stop the diesel freezing and turning into wax.


From what you've described you should be OK - I'd keep topping it up regularly for a couple of weeks to gradually dilute the petrol down even more, just to be on the safe side.

Iceweasel

There should be no problem with only 5litres of petrol with 55 litres of diesel.

ASAP add 250ml of 2-stroke oil - as used in lawn-mowers etc.

When the tank gets to half top up with another 30 litres of diesel.

Lots of people add a litre or 2 of petrol in periods of intense cold to prevent waxing so it'll be fine.

mchale

Iceweasel wrote: »

When the tank gets to half top up with another 30 litres of diesel.

Personally when you've done about 50 miles I would brim it again, and keep it brimmed like that, you want to dilute the petrol as much as possible.

Stoke

Use it today, then go and top up with some extra diesel to help it smoothly disperse.

You'll be fine

dannyrst

Most importantly, remove the keys from the wife.

iolanthe07

omeone else said it is worse if you put diesel in an unleaded car.

It is very difficult to do this, unless you use a can, because you can't put a diesel nozzle into a petrol filler hose.