Wattston: Petrol in a Diesel Car? How Worried to Be
Unstarted? Then less anxious than you probably are. "Have I wrecked it?" is the first question everyone around Wattston asks, and the truthful answer is normally no, because petrol left in a diesel tank hurts nothing till it is dragged through your fuel system — by ignition priming, by your starter, or by being driven. To keep the car like that, phone Petrol in Diesel and leave your engine alone. The remainder of this page covers what petrol really does to a diesel, how to tell how far it has got, and how to make sure it does not happen to you a second time.
Petrol in a diesel: what does it do to your engine?
Diesel has two jobs on its way through a motor. Oiling comes before burning; it does both. Extremely fine gaps are built into the fuel injectors and the high-pressure pump, and just your diesel flowing through stops those surfaces grinding together.
Of those two tasks, petrol manages the first poorly and the second never. A pump working on a petrol blend is wearing itself out, since petrol is runnier than diesel and takes away the lubrication the fuel system depends on. Petrol is also made to resist igniting under compression — the reverse of what a diesel wants from its fuel — and that is where any rattling comes.
Put those together and the shape of the problem is plain. Not contact but circulation is what does the damage. Any tank with petrol in it is a fuel problem. Once your pump has been running on that petrol, a mechanical fault has begun: whatever is shed by a pump that is wearing down is carried onward to the injectors with your fuel.
Petrol in a diesel around Wattston: how serious is it? Four situations
Filled up, not once started. The best case there is. At a forecourt, and truly only there, that petrol is still confined to the tank — because everywhere else the vehicle was driven to reach it. The job is emptying and cleaning on the spot.
Ignition on, or started for a moment. Petrol has left the tank and reached the filter and the lines, since the fuel system has been primed. That is usually still a straightforward task — a drain, a flush, and the fuel filter dealt with.
The pump has spent a couple of miles on diluted fuel — that is what driving the car meant. How hard the vehicle was driven matters as much as how far, and this work takes in the tank, your lines, your filter and clean fuel through the entire system. Driving the kids to the local primary school is one sort of trip. Any miles on the M80, under 5 miles from Wattston, means your engine working hard throughout, and a run to Glasgow, under 15 miles away, makes a very different task as well.
It complained, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone ragged. What you are hearing is your motor reporting fuel that no longer runs like diesel. Stop where you are — on the verge on Drumgray Lane, at the kerb, down a side road — and do not move it. What goes first is still the drain and flush, and that deals with it, with permanent damage very uncommon if a vehicle is pulled over soon.
Myths Wattston people hear about petrol in a diesel
It will not be fine. The myth: "Fill it the rest of the way with diesel and it'll be." Nothing comes out when you top up — your tank just carries more of the same blend. A diesel fuel system doesn't accept petrol by percentage in the way that advice supposes.
If anything, the reverse is true. Myth: "A current diesel can cope with a bit of petrol." More precise components and higher pressure are how a newer diesel runs its fuel, and that makes the lubrication matter more, not less.
Myth: "If it starts and drives, there is no harm done." This is the one that fools people. Feed diesel to a petrol engine and it usually won't run, so the driver stops — and the harm stops with them. A diesel fed petrol usually starts, idles and drives away as if nothing has happened, whilst the pump wears. Fine and running are not the same at all.
Myth: "Add some two-stroke oil and drive the car home." It's an outdated workaround for a distinct issue. What petrol has thinned stays diluted, and the petrol stays in your tank regardless.
"Drain it yourself and you're sorted" — a myth, since after it's been running some petrol sits in the filter and lines, ready to go right back through your pump on your next start. And, a can of petrol filled by the roadside is truly risky.
Petrol in a diesel: how does it take place?
On purpose? Never. Through carelessness? Seldom, if ever. One way only, because of the nozzles: the smaller petrol one slides inside a diesel filler with almost no resistance, whereas the diesel one mostly will not fit a petrol car. That is how the forecourt makes it simple.
When routine and the car stop matching, it occurs. A car that is new to you — a hire car, on loan as a courtesy car, or just bought. Two cars on one driveway, one petrol, one diesel. Your usual forecourt, its pumps now in a different order. Rushing for a train outside Greenfaulds and fuelling up en route. Precisely the moment it takes place: after years of driving petrol, a driver fills a diesel BMW 3 Series for the first time. With rain, a call coming in, or a car full of children to deal with, the hand just does what it always has.
Avoiding petrol in a diesel next time you fill up around Wattston
- Not every forecourt in the UK keeps to green for unleaded and black for diesel, even if most generally do. Read the pump's label; the colour is just a hint.
- Plenty of vehicles state the fuel inside your filler flap or on the cap, and so check it on the first fill in any motor you don't know.
- One of each in the home? Label the key to the diesel — a bright fob, a sticker — since intending to remember isn't enough.
- It sounds daft and it does the trick: on your first fill in a new or hired car, say "diesel" out loud before you lift the nozzle off the petrol pump.
- Thinking about something else is when this becomes an easy mistake to make, so put your phone away then keep your mind on the petrol pump.
- Some diesels come with a filler built to reject 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 pump.
- Stop the moment you realise. Less petrol in your tank means a weaker blend. It doesn't change what to do next, which is still not to fire it up.
Put petrol in a diesel around Wattston already?
Then, there's just a short order of things. Do not start the car, and do not turn your ignition on. Still at the forecourt, at Highland or anywhere else? Ask the attendants to help you roll the car away from the petrol pump. Next, 0333 366 0103. We'll ask what went in, roughly how much, and if it's been run.
Corrosion and deposits are the problem with AdBlue, whereas petrol brings lost protection. So if it was AdBlue, say so — and read its own Wattston page.
What makes one Wattston petrol in a diesel job cost more than the next
The four scenarios above are four different tasks, so no single price for this would be fair. The situation itself does most of the work of moving your cost. Where the car is matters too, and whether our van can safely reach it, after the share of petrol to what your tank holds.
Three queries come first, before any quote, instead of after — what went in, how much, has it run — and that is the reason. Their replies are what turn a range into one firm number.
About Wattston, briefly
Wattston is a small village in North Lanarkshire, situated on the riverside at an elevation of 188 metres. Wattston lies near several other communities, including Riggend, Greengairs, and Stand, and is approximately 11 miles from Glasgow. Wattston has a population of around 549 people, predominantly living in detached houses. Wattston is also relatively distant from London, at around 342 miles away.
Fuel drain cover across North Lanarkshire, Wattston included
Petrol in diesel call-outs in Wattston — part of the ML postcode area — go to vans that likewise cover the locations around it, Riggend, Greengairs and Stand among them. A forecourt, a supermarket car park, a lay-by or your own driveway are all spots our technicians work, and your vehicle does not need to come to us.
Still at the pump in Wattston?
The best spot there is, then — that's where you are. Switched off it stays; then phone.