Petrol in a Diesel Car in Beeslack: How Worried Should You Be?
Not started? Then less anxious than you probably are. Till your ignition primes the pump, the starter turns, or your car is driven, petrol in a diesel tank simply waits there and does nothing. Which makes the truthful reply to that first Beeslack question — "have I ruined it?" — usually no. To keep it that way, call Petrol in Diesel then leave the engine alone. What petrol actually does to a diesel, how to judge how far it's gone, and how to stop it from happening again: that is the remainder of this page.
Petrol in a diesel: what does it do to your engine?
On its way through an engine, diesel does two jobs. Oiling comes before burning; it does both. The high-pressure fuel pump and the fuel injectors are built to extremely fine tolerances, and your diesel passing through them is what stops those surfaces from wearing against each other.
The second task petrol does not do at all, and the first it does badly. It's thinner than diesel and removes the protection the system rests on, so a pump running on a petrol mix is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the reverse of what a diesel needs from its fuel. That is where the rattling comes from.
Put these together and the shape of the trouble is plain. It is circulation that does the harm, not contact. All a tank with petrol in it amounts to is a fuel issue. The start of a mechanical problem is a pump that has been labouring on that petrol — and whatever a worn pump sheds travels on with the fuel to the injectors downstream.
How bad is petrol in a diesel? Four scenarios we see in Beeslack
Filled up, never started. The best case there is. Only the tank has petrol in it, so the job is draining your tank and purging the system where the car stands. This scenario can only really happen at a forecourt: anywhere else, the car got there by being driven.
Ignition on, or started for a second. With the fuel system primed, the lines and filter already contain petrol that came from your tank. Usually nothing more than emptying, purging and sorting the fuel filter, and so still straightforward.
A few miles driven, and your pump has spent each of them labouring on diluted fuel. Tank, lines, filter, then clean fuel put through the whole circuit: that is this work, and the way your car was driven matters as much as the miles. Driving the children to the local primary school is one kind of trip. Very different once more: a run to Edinburgh, under 10 miles away, or some mileage on the M8, under 10 miles from Beeslack, where your engine kept labouring hard.
Driven on till it protested — knocking, smoke, a ragged idle, a soft throttle. The fuel is not behaving like diesel any more, and the motor is telling you. Stop wherever you are — the verge on Edinburgh Road, a lay-by, a side street — then leave it where it is. The fuel drain and flush still go first, and they sort it out: if a car is pulled over quickly, lasting damage is very uncommon.
Petrol in a diesel stories Beeslack motorists hear
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. Nothing is removed when you top up — the tank just carries more of the same blend. A diesel fuel system does not accept petrol by percentage in the way that advice assumes.
Myth: "A current diesel can cope with a bit of petrol." If anything, the reverse. A current diesel runs its fuel through finer components at higher pressure, which makes the protection count more, not less.
Myth: "If it starts and drives, there is no harm done." This is the one that fools drivers. The motorist of a petrol motor fed diesel normally stops, since it will not run, and the harm stops there. Feed petrol to a diesel and it usually fires up, ticks over and drives away like nothing has happened — all the while its pump wears. Running isn't the same as fine.
An outdated fix for a separate problem lies behind this one. Myth: "Add some two-stroke oil and drive the car home." What petrol has thinned remains diluted, and the petrol remains inside that tank regardless.
"Drain it yourself and you're sorted" — a myth, because after it has been running some petrol sits in the fuel filter and lines, ready to go straight back through the pump at the next start. It is also genuinely dangerous to drain petrol into a can by the roadside.
How it happens: petrol in a diesel
On purpose? Never. Through carelessness? Seldom, if ever. One way only, because of the nozzles: the narrower petrol one slides inside a diesel filler with almost no resistance, while the diesel one mostly won't fit a petrol motor. That is how the forecourt makes it simple.
When routine and the vehicle stop matching, it takes place. Courtesy car, hire car, or a motor that is new. Households running one of each, petrol and diesel. The pumps in a different order on a well-known forecourt. Fuelling up in a hurry en route to Wester Hailes, with a train to catch. A new-to-you diesel Volkswagen Golf, its first fuelling, and a driver accustomed to petrol: precisely when it happens. With rain, a call arriving, or children to deal with, the hand simply does what it always has.
Preventing petrol in a diesel next time you fill up around Beeslack
- Read the petrol pump, not the colour. In the UK unleaded handles are usually green and diesel black, but not on each forecourt. The label is what matters.
- In a vehicle you do not know, look inside the flap over the filler or at the cap before your first fill: many cars print the fuel type there.
- Good intentions count for less than a sticker or a fob in a vivid colour on your diesel's key when a house has one of each. So mark it.
- "Diesel", aloud, before you lift the nozzle — every time a new or hired car gets its first tank. It seems silly. It does the trick.
- Thinking about something else is when this becomes an easy mistake to make, and so tuck the phone away and keep your mind on the petrol pump.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler designed to refuse a petrol nozzle, and add-on devices are available for the remainder. Treat it as a backstop, and keep checking the pump.
- Stop the moment you notice. Less petrol inside that tank means a thinner mixture. It does not change what to do next, which is still not to crank it.
Petrol already in a diesel around Beeslack? Begin here
The order of things is brief, then. Starting it is out, and so is switching on your ignition. The staff on the forecourt — whether at Tesco itself or wherever you filled up — will normally help push it away from the pump if you ask. Next, 0333 366 0103. We will ask what was put in, roughly how much, and if it has been run.
If it was AdBlue and not petrol, say so. That's a separate problem — corrosion and deposits rather than lost lubrication — and it has its own page for Beeslack.
What makes one Beeslack petrol in a diesel job cost more than the next
There's no fair single quote for this, since the four scenarios above are four separate tasks. Mostly, your cost shifts with which one you are in. Where the car is matters too, and whether a van can safely reach it, after the proportion of petrol to what the tank takes.
What went in, how much, and if it has run — three queries our technicians ask before pricing, not after, for exactly that reason. Their answers are what change a range into one firm number.
About Beeslack itself
Beeslack is a suburban area situated on the riverside in Midlothian, with a mix of terraced housing and a population of around 4118 residents. Beeslack sits at an elevation of 174 metres, close to the nearby communities of Mauricewood, Greenlaw Mains, and Ladywood. Beeslack is located near Edinburgh, Scotland's capital city, which is approximately 7.9 miles away. Beeslack forms part of the wider Edinburgh urban area, with the city's amenities and services within easy reach.
Fuel drain cover around Beeslack and across Midlothian
Mauricewood, Greenlaw Mains and Ladywood are among the spots near Beeslack that the same vans work, answering petrol in diesel jobs across Beeslack's EH postcode area. We drain where your car is — your own driveway, a lay-by, a supermarket car park, a forecourt — so it does not have to come to us.
At the petrol pump around Beeslack, right now?
Then you are in the best spot there can be. Keep it off. Call.