How Worried Should You Be? Petrol in a Diesel Car in Bughtlin
Probably less than you are now — as long as nobody has started the car. Till your ignition primes your pump, your starter turns, or the car is driven, petrol in a diesel tank just sits there and does nothing. Which makes the honest reply to that first Bughtlin question — "have I ruined it?" — usually no. Leave your motor off and call Petrol in Diesel — that is how you keep it that way. Below, you will find what petrol actually does inside a diesel, how far it may have gone, and how to stop it happening to you a second time.
What petrol in a diesel does to the motor
Diesel has two tasks on its way through an engine. It ignites, and before it burns it lubricates. The high-pressure pump and the injectors are made to extremely fine clearances, and your diesel passing through them is what keeps those surfaces from wearing against each other.
Of those two tasks, petrol handles the first poorly and the second never. Being less viscous than diesel, petrol strips out the lubrication a fuel system needs, so a pump running on that mixture to wear itself. It is also made to resist igniting under compression — the reverse of what a diesel needs — which is where you hear the clattering.
Put these together and the shape of the issue is plain. It is circulation that does the harm, not contact. Petrol in the tank is a fuel fault. A pump that has been labouring on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds travels on with the fuel to your injectors further on.
Four scenarios our technicians see around Bughtlin: how serious is petrol in a diesel?
Filled but never started — as good as it gets. On a forecourt, and truly only there, that petrol is still confined to your tank — since everywhere else the car was driven to get to it. The job is emptying and rinsing on the spot.
Started for a second, or only your ignition on. Petrol has left the tank and reached your filter and the fuel lines, since the system has been primed. Normally little more than emptying, rinsing and sorting the fuel filter, and so still easy.
A few miles driven, and your pump has spent each of them working on diluted fuel. How hard the car was driven counts as much as how far, and the work takes in your tank, your lines, the fuel filter and clean fuel through the entire system. The school run to the local primary school is one matter. Any miles on the M8, under 3 miles from Bughtlin, means the engine has worked hard throughout, and a run to Edinburgh, under 5 miles away, makes a very different job as well.
Driven till it protested. Clattering, an uneven idle, smoke, a throttle that has gone soft. The fuel isn't acting like diesel any more, and your engine is saying so. Leave it where it has stopped: a lay-by, a side street, the verge on Maybury Drive. What goes first is still the fuel drain and flush-through, and that deals with it, with permanent damage very uncommon when a vehicle is stopped quickly.
Petrol in a diesel myths Bughtlin drivers hear
Myth: topping up to full with diesel makes it fine. It does not. Nothing comes out when you top up — your tank just carries more of the same blend. That advice presumes a diesel fuel system handles petrol by percentage. It doesn't.
"Current diesels can handle a little petrol" — a myth, and nearer the reverse. A modern diesel sends its fuel through finer parts at higher pressure, which makes the lubrication matter more, not less.
"It starts, it drives, so there is no harm" — the myth that trips up most motorists than any other. Diesel in a petrol motor normally means a motor that will not run: the driver stops, and so does the harm. Nothing seems to have happened when a diesel fed petrol fires up, ticks over and drives away, which it usually will; meanwhile the pump wears. Running is not the same as fine.
"A drop of two-stroke oil and drive it home" — a myth, borrowed from a fix from years ago, for a distinct issue. It doesn't put back what petrol has thinned, and that petrol is still in the tank later.
Myth: "Drain that tank yourself and you're sorted." After the engine has run, some of the petrol is no longer inside the tank: it's in the fuel filter and the lines, and it goes straight back through your pump on your next start. Emptying petrol into a can by the kerbside is also really hazardous.
Petrol in a diesel: how does it occur?
Nobody does it on purpose, and it is seldom carelessness. One way only, since of the nozzles: the narrower petrol one slides inside a diesel filler with almost no resistance, while the diesel one generally will not fit a petrol car. That is how the forecourt makes it straightforward.
When habit and your car stop matching, it happens. A new motor, a hire car or a courtesy car. Two motors on one drive, one petrol, one diesel. A well-known forecourt with the pumps in a different order. Rushing for a train at Edinburgh Gateway and filling up en route. Exactly the moment it takes place: after years of driving petrol, someone fills a diesel Renault Megane for the first time. Throw in a back seat full of kids, a phone call or rain, and the hand takes over.
Next time you fill up in Bughtlin: avoiding petrol in a diesel
- Not every forecourt in the UK follows green for unleaded and black for diesel, though most usually do. Check the pump's label; the colour is just a clue.
- Plenty of vehicles state the fuel type inside your filler flap or on the cap, and so check it on your first fill in a motor you don't know.
- Good intentions do less than a sticker or a fob in a bright colour on the diesel's key if a home has one of each. So label it.
- It sounds silly and it does the trick: on your first fill in a new or hired car, say "diesel" aloud before you take the nozzle off the petrol pump.
- Put the phone away. This is an easy mistake to make whilst you're thinking about something else.
- Up to a point, a misfuel inhibitor helps: some diesels have a filler designed to block a petrol nozzle, and add-on devices are available for the remainder. Treat it as a backstop, then keep reading the petrol pump.
- The moment you notice, stop: less petrol in that tank makes a thinner blend. What to do next does not change, though — still don't crank it.
Put petrol in a diesel in Bughtlin already?
The order of things is brief, then. Never start the vehicle, and don't turn the ignition on. Ask the staff to help you roll it clear of the pump if you are still at the forecourt, whether that is Shell or somewhere else. Next, 0333 366 0103. We will ask what went in, about how much, and if it has been run.
If it was AdBlue instead of petrol, say so. That is a separate fault — corrosion and deposits instead of lost lubrication — and it has its own page for Bughtlin.
Bughtlin petrol in a diesel tasks: why one costs more than another
A fair single price doesn't exist here: four scenarios, four separate tasks. What shifts your cost is chiefly which of them you are in. Where your car is counts too, and whether a van can safely get to it, after the proportion of petrol to what your tank holds.
That is why our technicians ask three queries before costing instead of after: what was put in, how much, and if it's run. The replies change a range into a straight figure.
About Bughtlin and where it is
Bughtlin is a coastal suburban area in the City of Edinburgh, situated approximately 4.5 miles from Edinburgh city centre. Bughtlin sits at an elevation of 51 metres, with the area being predominantly composed of flat housing. Bughtlin is located near other suburban areas such as Drumbrae, East Craigs, and The Gyle, and is home to a population of around 6724 residents.
Fuel drain cover across City of Edinburgh, Bughtlin included
Bughtlin rests in the EH postcode area, and our vans that answer petrol in diesel jobs there work the locations near it as well — Drumbrae, East Craigs and The Gyle among them. You need not bring your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all spots we drain.
Bughtlin: still at the petrol pump?
Then you're in the best place there is. Keep it off. Ring.