Radnor: Petrol in a Diesel Car? How Worried to Be
Provided it hasn't been started, worry less than you probably are. Everyone around Radnor starts with "have I ruined it?", and the fair answer is usually no: petrol resting in your tank of any diesel remains harmless until priming, cranking or driving draws it into your fuel system. To leave the vehicle that way, call Petrol in Diesel and leave the motor alone. Keep reading for three things: the effect petrol has inside a diesel motor, the signs of how far it has got, and ways to make sure you never repeat it.
Your engine and petrol in a diesel: what happens
Two tasks fall to diesel on its route through a motor. It protects to begin with, and after that does it burn. What stops the surfaces inside your high-pressure pump and your injectors from grinding against each other is your diesel flowing through them — they are made to extremely fine gaps.
The second job petrol doesn't do at all, and the first it does poorly. It's thinner than diesel and takes away the lubrication your fuel system rests on, so a pump running on a petrol blend is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the opposite of what a diesel needs from its fuel. That's where the clattering comes from.
Combined, those make the shape of the problem clear. It's circulation that causes the harm, not contact. A tank with petrol in it is a fuel problem. Whatever a worn pump sheds travels on, borne by your fuel, into the fuel injectors further along, which is why a pump that has been working on the petrol is where a mechanical issue begins.
Four situations we see in Radnor: how serious is petrol in a diesel?
The best case there is: filled up, never started. Being at a forecourt is what makes this the case: elsewhere, your car has been driven there to begin with. With that petrol held in the tank alone, it's cleared and cleaned on the spot, and nothing more is needed.
Ignition on, or started for a moment. The fuel system has been bled, and so petrol has left the tank and reached your filter and the lines. Normally little more than emptying, rinsing and sorting your filter, so still straightforward.
Those few miles on the road meant your pump running on fuel weakened by petrol the whole way. Mileage is only half of it; how hard it was driven matters equally. Either way the work runs to that tank, the fuel lines, the filter and clean fuel through the whole circuit. On the school run to Black Firs Primary School, the distance is short. Very different again: a trip to Stoke-on-Trent, under 15 miles away, or any distance on the M6, under 5 miles from Radnor, where your engine never stopped running hard.
It complained, and only then stopped: smoke, knocking, a throttle gone soft, an idle gone ragged. The fuel isn't acting like diesel any more, and the motor is saying so. Whether it's the verge on Black Firs Lane, a lay-by or a side road, stop there and leave it. The fuel drain and flush still come first, and they sort it out: when a car is pulled over early, permanent damage is very unusual.
Stories Radnor motorists hear about petrol in a diesel
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It will not. A bigger tank of the same mixture is all it gives, since topping up removes nothing. A diesel fuel system doesn't accept petrol by percentage in the way that advice supposes.
If anything, the opposite is true. Myth: "A current diesel can cope with a bit of petrol." A newer diesel runs its fuel through finer components at higher pressure, which makes the protection count more, not less.
This is the one that catches drivers. Myth: "If it starts and drives, there's no damage done." Diesel in a petrol motor normally means a motor that won't run: the driver stops, and so does the harm. Whilst your pump wears, a diesel fed petrol usually starts, ticks over and drives away as though nothing has happened. Fine and running aren't the same thing.
Not so: a two-stroke additive makes it safe to drive home. It was an old workaround, supposed for another problem. What petrol has thinned remains thinned, and the petrol stays inside the tank regardless.
Myth: "Drain the tank yourself and you are sorted." Once the motor has run, some of the petrol is no longer inside your tank: it is in the filter and the fuel lines, and it goes straight back through your pump at your next start. Emptying petrol into a can at the roadside is also truly dangerous.
How does petrol in a diesel occur?
Nobody does it on purpose, and it is seldom carelessness. One way only, since of the nozzles: the smaller petrol one slides inside a diesel filler with almost no resistance, whereas the diesel one generally won't fit a petrol vehicle. That is how the forecourt makes it simple.
When routine and the car stop matching, it takes place. Courtesy car, hire car, or a car that's new. A household with one petrol and one diesel on the drive. Your normal forecourt, its pumps suddenly in a different order. A train to catch, and a hurried fill on the way to Congleton. A new-to-you diesel Volkswagen Tiguan, its first fuelling, and a driver used to petrol: precisely when it happens. Add a back seat full of kids, a phone call or rain, and habit wins.
Radnor people: how to avoid petrol in a diesel next time
- A green handle for unleaded and black for diesel is normal in the UK — yet not on each forecourt. Trust the label on the petrol pump, not the colour.
- Plenty of motors state the fuel type inside the filler flap or on the cap, so check it on the first fill in any motor you do not know.
- Label 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 intending to remember.
- Before the nozzle comes off the pump the first time you fuel a hired or new motor, say "diesel" out loud. Silly, yes, but it does the trick.
- Mistakes like this are straightforward to make whilst your mind is on something else, so the phone goes away.
- Add-on devices are available for motors without one, and some diesels come with a filler that won't accept a petrol nozzle. Helpful — but a backstop only, never a reason to stop checking the label.
- Stop as soon as you realise. Less petrol inside the tank means a thinner mix. It doesn't change what to do next, which is still not to start the vehicle.
Put petrol in a diesel around Radnor already?
Short and simple, then, is the order of things. Leave it unstarted, with the ignition off as well. The attendants on the forecourt — whether at BP itself or wherever you filled up — will normally help push it clear of the pump if you ask. Then phone 0333 366 0103 and tell us what was put in, roughly how much, and whether it's run.
Corrosion and deposits form the issue with AdBlue, whereas petrol brings lost lubrication. So if it was AdBlue, say so — and read its own Radnor page.
One petrol in a diesel task around Radnor costs more than another. Why?
There's no fair single quote for this, since the four scenarios above are four different tasks. What shifts your cost is chiefly which of them you are in. The proportion matters next, meaning how much of your tank is petrol, and then the position of the vehicle and whether getting to it is safe for a van.
What got in, how much, and if it's run — three questions our engineers ask before costing, not after, for exactly that reason. Those answers are what turn a range into one firm number.
About Radnor and where it is
Radnor is a small hamlet situated on the riverside in Cheshire, with an elevation of around 91 metres. Radnor lies near the villages of Somerford Booths and Wornish Nook, and is approximately 11 miles from Stoke-on-Trent. Radnor has a population of around 841 people, predominantly living in detached houses. Radnor is located in the North West region of England, about 146 miles from London.
Fuel drain cover in Radnor and across Cheshire
Radnor sits in the CW postcode area, and the vans that answer petrol in diesel call-outs there work the places near it as well — Somerford Booths, Wornish Nook and West Heath among them. You need not move the car to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all spots where we work.
In Radnor and still at the petrol pump?
Then you're in the best position there can be. Leave it switched off, and ring.