Should You Worry? Petrol in a Diesel Car in Walrow
Unstarted? Then less worried than you likely feel. Till your ignition primes your pump, your starter cranks, or your car is driven, petrol in a diesel tank simply rests there and does no harm. Which means the truthful reply to that first Walrow question — "have I wrecked it?" — usually no. To keep the vehicle like that, call Petrol in Diesel then leave the engine alone. The rest of this page sets out what petrol really does to a diesel, how to judge 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 the motor?
Passing through an engine, diesel does two jobs at the same time. Before it ignites, it protects — and then it combusts. Designed to extremely fine clearances, your injectors and the pump rely on your diesel moving through them to stop their surfaces wearing against one another.
Petrol does the first task badly and the second not at all. The knocking comes from petrol being made not to ignite when compressed, which is exactly the reverse of what a diesel needs. On top of that it is thinner than diesel, it strips away the lubrication the fuel system depends on, and any pump running on that blend is wearing itself.
Put those together and the shape of the trouble is clear. The harm is done by circulation, not by contact. Petrol in the tank is a fuel problem. Whatever a worn pump sheds travels on, carried by the fuel, into your injectors downstream, which is why a pump that has been working on that petrol is where a mechanical problem begins.
Walrow, petrol in a diesel: four cases, from mild to significant
The best case there is: filled up, not once started. That petrol is inside the tank and only the tank, and the job is a drain and a flush where the car sits. This is the one situation that can only really happen at a forecourt, since anywhere else the car has been driven to get there.
Ignition on, or started for a second. With your system primed, your lines and filter now contain petrol that has come from your tank. Normally nothing more than emptying, cleaning and sorting the filter, so still straightforward.
A couple of miles driven, and the pump has spent each of them running on thinned fuel. Distance is only half of it; how hard it was driven matters just as much. Either way the work includes that tank, the lines, the fuel filter and clean fuel through the whole system. Driving the children to Churchfield Church School is one kind of trip. Very different once more: a trip to Wells, under 15 miles away, or some distance on the M5, under a mile from Walrow, where the motor kept working hard.
Driven until it protested. Clattering, a ragged idle, smoke, a throttle that has gone soft. That's your motor telling you its fuel has stopped behaving like diesel. Leave it where it stops: a lay-by, a quiet street, the verge on M5. The fuel drain and flush-through still come first, and they sort it out: when a car is pulled over soon, long-term damage is very uncommon.
Stories Walrow motorists hear about petrol in a diesel
False: topping up to full with diesel makes it fine. It doesn't. A bigger tank of the same mix is all you get, because topping up removes nothing. The idea behind that advice — that diesel fuel systems tolerate petrol by percentage — is wrong.
Myth: "A newer diesel can cope with a bit of petrol." If anything, the opposite. A current diesel runs its fuel through finer components at higher pressure, which makes the lubrication matter more, not less.
One myth that catches motorists out: if it starts and drives, it must be unharmed. Feed diesel to a petrol motor and it usually will not run, so the driver stops — and the damage stops with them. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually does; meanwhile your pump wears. A running engine doesn't mean fine.
Not so: a two-stroke additive lets you to drive home. It was an old workaround, meant for another issue. None of what petrol weakened gets put back by it — and later, the tank still contains the petrol.
"Drain it yourself and you are sorted" — a myth, because after it's been running some petrol sits in the filter and lines, waiting to go straight back through your pump at the next start. Draining petrol into a can at the kerbside is also truly risky.
Petrol in a diesel: how does it happen?
On purpose? Never. Through carelessness? Seldom, if ever. The petrol nozzle is the narrower of the two and slips into a diesel filler with almost no resistance; a diesel nozzle generally will not go into a petrol car at all. The forecourt makes it simple, and the mistake runs one way.
Routine and the vehicle getting out of step is how it occurs. Courtesy car, hire car, or a motor that's brand new. A household with one petrol and one diesel on the driveway. A familiar forecourt with the pumps in a different order. A hurried fill en route to Highbridge & Burnham with a train to catch. Years of petrol cars behind you, a diesel Renault Clio in front of you at the forecourt for its first tank — that is when. Throw in rain, a phone call or a back seat full of children, and your hand repeats what it has always done.
Avoiding petrol in a diesel next time you fill up around Walrow
- Check the petrol pump, not the colour. In the UK unleaded handles are normally green and diesel black, yet not on each forecourt. The label is what matters.
- Plenty of vehicles state the fuel type inside the filler flap or on the cap, and so check it on your first fill in a vehicle you don't know.
- Mark your key. In a home with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of meaning to remember.
- Before the nozzle comes off the petrol pump the first time you fill a hired or new vehicle, say "diesel" aloud. Daft, yes, but it does the trick.
- Tuck your phone away. This is an easy mistake to make while you are thinking about something else.
- Add-on devices exist for vehicles without one, and some diesels come with a filler that will not take a petrol nozzle. Helpful — but a backstop at best, never a reason to stop checking the label.
- Spotting it mid-fill? Stop there and then. A weaker mix results from less petrol inside that tank, yet your next stage stays the same: do not start the vehicle.
Already put petrol in a diesel around Walrow?
The order of things is brief, then. Leave it unstarted, with the ignition switched off too. If you're still on the forecourt — Asda or anywhere else — ask the staff to help you push the vehicle clear of the pump. Then call 0333 366 0103 and tell us what was put in, roughly how much, and whether it's run.
AdBlue, not petrol? Then tell us. Corrosion and deposits, not lost protection, make it a different problem — Walrow has a page all for it.
One petrol in a diesel job around Walrow costs more than another. Why?
The four situations above are four separate jobs, so no single quote for this would be fair. Which of them you are in is mostly what shifts the cost. Two things follow that: the petrol that went in as a share of what your tank holds, then the spot the car is in and whether a van can get to it safely.
Before any quote, not after, come three questions: the fuel that was put in, its quantity, and whether it has run. That's why. Those replies change a range into a straight figure.
About Walrow itself
Walrow is a small coastal locality in Somerset, situated near the mouth of the River Brue and close to the villages of Watchfield and Highbridge. Walrow lies at a low elevation of around 5 metres, making it a flat and low-lying area. Walrow is characterized by its predominantly detached housing stock, reflecting its residential nature. Walrow is located near the city of Wells, which is approximately 13 miles away.
Fuel drain cover across Somerset, Walrow included
Walrow waits in the TA postcode area, and our teams that answer petrol in diesel calls there work the places around it as well — Watchfield, Highbridge and Edithmead among them. The car doesn't need to come to us: our technicians drain on a forecourt, in a supermarket car park, in a lay-by or on your own driveway.
At the petrol pump in Walrow, right now?
Nothing beats it: that's where you are. Keep it off. Ring.