How Worried Should You Be? Petrol in a Diesel Car in Hill of Banchory
If it hasn't been started, worry less than you likely are. Until the ignition primes the pump, your starter cranks, or the vehicle is driven, petrol in a diesel tank simply sits there and does no harm. Which means the truthful reply to that first Hill of Banchory question — "have I wrecked it?" — normally no. To keep the car that way, phone Petrol in Diesel and leave your engine alone. Further down, this page sets out what petrol really does inside a diesel, how far it might have gone, and how to stop it happening to you again.
Petrol in a diesel: what does it do to the engine?
Passing through a motor, diesel does two things at once. Before it burns, it lubricates — and then it burns. The high-pressure fuel pump and the fuel injectors are designed to very fine clearances, and your diesel passing through them is what keeps those surfaces from grinding against one another.
The second task petrol doesn't do at all, and the first it does poorly. Being less viscous than diesel, petrol strips out the protection a fuel system needs, so a pump running on the mixture to wear itself. It is equally made to resist igniting under compression — the opposite of what a diesel needs — which is why you get the rattling.
Together, those make the shape of the issue clear. Contact doesn't do the damage — circulation does. Where that petrol is only in that tank, it is an issue of fuel, nothing more. Once your pump has been running on that petrol, a mechanical problem has begun: anything shed by a pump that's grinding travels onward to your injectors with your fuel.
Four scenarios our technicians see around Hill of Banchory: how serious is petrol in a diesel?
Filled but not once started — as good as it gets. Only that tank has petrol in it, and so the task is clearing the tank and rinsing your system where your car sits. This situation can only truly occur on a forecourt: anywhere else, the vehicle got there by being driven.
Your ignition switched on, or a brief start. With the fuel system primed, your lines and filter now hold petrol that has come from your tank. Still generally easy: drain, flush, and the fuel filter dealt with.
A few miles driven, and your pump has spent every one of them labouring on thinned fuel. Mileage is only half of it; how hard it was driven matters just as much. Either way this work includes that tank, the lines, your filter and fresh fuel through the entire system. On the school run to the local primary school, the mileage is small. Any mileage on the M90, over 50 miles from Hill of Banchory, means the motor working hard throughout, and a run to Aberdeen, under 25 miles away, is a very different task too.
Driven on till it complained — knocking, smoke, a ragged idle, a soft throttle. The fuel isn't acting like diesel any more, and your motor is saying so. Pull up wherever you are — the verge on Forestside Drive, a lay-by, a side street — and leave the vehicle where it is. Long-term damage is very unusual when a car is stopped quickly, and the drain and flush that still come first deal with it.
Petrol in a diesel stories Hill of Banchory motorists hear
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It won't. Nothing is removed by topping up — you are left with a fuller tank, still the same mix. A diesel fuel system doesn't accept petrol by percentage in the way that advice assumes.
Not so: a modern diesel copes with a bit of petrol. If anything, the reverse. Lubrication counts more on modern diesels, not less, because their fuel runs through more precise components at higher pressure.
Myth: "If it starts and drives, there is no harm done." This is the one that catches motorists. Any petrol engine fed diesel generally will not run, and so the motorist stops and the damage stops with them. A diesel fed petrol normally starts, ticks over and drives away as if nothing has happened, whilst the pump grinds. Fine and running aren't the same thing.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a different fault. What petrol has thinned stays thinned, and that petrol remains inside the tank anyway.
The next start sends petrol back round your pump from the fuel lines and the fuel filter, where some of that ends up after the motor has run. That is why a DIY tank drain does not sort it — a myth. It's also really dangerous to drain petrol into a can by the roadside.
How it happens: petrol in a diesel
It's rarely carelessness, and no one does it on purpose. A diesel nozzle mostly won't fit a petrol motor, yet the narrower petrol nozzle goes into the filler of a diesel nearly without resistance — so forecourts make this one mistake simple, and only in that direction.
It occurs when habit and your car stop matching. Hire cars, courtesy cars, and cars that are new to you. A household with one petrol and one diesel on the drive. A familiar forecourt with the pumps in a different order. A train to catch, and a rushed fill on the way to Stonehaven. The first fill-up in a diesel Renault Megane after years of driving petrol is precisely the moment it takes place. The hand does what it has always done once you add rain, a phone call or a back seat full of children.
Hill of Banchory drivers: how to prevent petrol in a diesel next time
- Green for unleaded and black for diesel is normal in the UK — but not on every forecourt. Go by the label on the pump, not the colour.
- In a motor you do not know, look inside the flap over your filler or at the cap before your first fill: plenty of vehicles print the fuel there.
- Mark your key. In a home with one of each, a coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember.
- It sounds daft and it does the trick: on your first fill in a new or hired car, say "diesel" out loud before you take the nozzle off the petrol pump.
- Tuck your phone away. This is an easy mistake to make whilst you're thinking about something else.
- Some diesels come with a filler designed to refuse a petrol nozzle, and devices you can add are available for cars without one. Such an inhibitor helps up to a point — as a backstop, not a reason to stop reading the petrol pump.
- Spotting it mid-fill? Stop at once. A thinner blend results from less petrol in the tank, but the next stage stays the same: do not start the vehicle.
Put petrol in a diesel in Hill of Banchory already?
Then, there's only a short order of things. Leave it unstarted, with your ignition off as well. Ask the attendants to help you push it clear of the petrol pump if you are still at the forecourt, whether that's Morrisons or anywhere else. What was put in, about how much, and whether it has run: tell us those when you call 0333 366 0103.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost lubrication, make it a different fault — Hill of Banchory has a page just for it.
Hill of Banchory petrol in a diesel tasks: why one costs more than another
Four separate tasks lie behind the four scenarios above — which is why there's no fair single quote. Which of them you are in is chiefly what moves your cost. Beyond that it is the ratio — how much petrol went in against how much the tank holds — and then where your car is and whether our van can get to it safely.
That's why we ask three queries before costing instead of after: what was put in, how much, and whether it's run. Their answers are what turn a range into one firm number.
About Hill of Banchory, briefly
Hill of Banchory is a locality in Aberdeenshire, situated inland at an elevation of around 85 metres, near the city of Aberdeen. Hill of Banchory is characterized by its predominantly detached housing stock, reflecting the area's residential nature. Hill of Banchory is close to several nearby places, including Upper Lochton, Silverbank, and Lochton of Leys, and is located approximately 16 miles west of Aberdeen.
Across Aberdeenshire and around Hill of Banchory: fuel drain cover
Petrol in diesel jobs in Hill of Banchory — part of the AB postcode area — go to vans that also cover the places about it, Upper Lochton, Silverbank and Lochton of Leys included. Our technicians drain where the car is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
In Hill of Banchory and still at the pump?
The best place there is, then — that is where you are. Turned off it remains; then call.