Petrol in a Diesel Car in Wych: How Worried Should You Be?
Provided it has not been started, you can worry less than you probably are. Till the ignition primes your pump, the starter cranks, or your vehicle is driven, petrol in a diesel tank just sits there and does nothing. Which makes the truthful reply to the first Wych question — "have I ruined it?" — usually no. Petrol in Diesel is who to call, with the engine left off, so it stays that way. Read on for three things: the effect petrol has inside a diesel motor, the clues of how far it has spread, and the way to make sure you don't do it again.
The engine and petrol in a diesel: what happens
Passing through a motor, diesel does two things at the same time. Before it combusts, it lubricates — and then it burns. What stops the surfaces inside the high-pressure pump and the fuel injectors from wearing against one another is the diesel passing through them — they're built to very fine clearances.
Of those two tasks, petrol handles the first poorly and the second never. The clattering comes from petrol being designed not to ignite when compressed, which is precisely the opposite of what a diesel needs. On top of that it is thinner than diesel, it strips away the protection your system hinges on, and any pump running on that mixture is wearing itself.
The shape of the problem is clear once you put those together. The damage is done by circulation, not by contact. Where that petrol is only in that tank, it's a problem of fuel, nothing more. The beginning of a mechanical one is a pump that has been labouring on that petrol — and whatever a worn pump sheds moves on with the fuel to your injectors beyond it.
Petrol in a diesel around Wych: how serious is it? Four situations
Fuelled up, never started. The best case there is. On 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 task is emptying and cleaning on the spot.
A brief spell of running, or merely the ignition on. The fuel system has been bled, and so petrol has left your tank and reached your filter and the lines. Drain, flush, see to your filter: still usually easy.
Those few miles on the road meant the pump running on fuel weakened by petrol throughout. Miles is only half of it; how hard it was driven matters just as much. Either way this work includes the tank, the fuel lines, the fuel filter and clean fuel through the whole system. On the school run to Bridport, St Mary's Church of England Primary School, the distance is small. Any distance on the M5, under 25 miles from Wych, means the engine has worked hard throughout, and a run to Exeter, under 50 miles away, is a very different task too.
Driven on till it protested — clattering, smoke, an uneven idle, a dead throttle. That is your engine telling you its fuel no longer is behaving like diesel. Pull up wherever you are — the verge on Wychside Close, a lay-by, a side street — then leave it where it is. What goes first is still the drain and flush, and that sorts it out, with permanent damage very rare when a vehicle is pulled over quickly.
What Wych motorists get told about petrol in a diesel — and the myths in it
Myth: topping up to full with diesel makes it fine. It does not. Topping up removes nothing; it gives you a bigger tank of the same mix. Percentage isn't how a diesel fuel system copes with petrol, however much that guidance supposes.
If anything, the reverse holds. Myth: "A newer diesel can cope with a bit of petrol." A current diesel runs its fuel through finer components at higher pressure, which makes the lubrication matter more, not less.
Myth: "If it starts and drives, there is no damage done." This is the one that fools motorists. Diesel in a petrol motor usually means a motor that will not run: the motorist stops, and so does the harm. While the pump wears, a diesel fed petrol usually starts, ticks over and drives away as if nothing has happened. Being able to run is not the same as being fine.
Myth: a two-stroke additive lets you to drive home. It is an old fix, supposed for another issue. It does not put back what petrol has diluted, and that petrol is still inside the tank after that.
"Drain it yourself and you're sorted" — a myth, since after it's been running some petrol sits in your filter and lines, ready to go straight back through the pump on the next start. Besides, petrol drained into a can by the road is truly risky.
Why petrol in a diesel occurs at all
It is seldom carelessness, and no one does it on purpose. A diesel nozzle mostly will not go into a petrol vehicle, yet the slimmer petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one error easy, and only in one direction.
The moment routine stops matching the car is the moment it happens. Hire cars, courtesy cars, and vehicles that are new to you. A household with one petrol and one diesel on the driveway. A forecourt you know, only with its pumps laid out differently. Rushing for a train outside Maiden Newton and fuelling up en route. A new-to-you diesel Renault Megane, its first fuelling, and a driver accustomed to petrol: precisely when it takes place. Throw in rain, a phone call or a back seat full of children, and the hand does what it has always done.
Wych motorists: 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 every forecourt. Go by the label on the petrol pump, not the colour.
- In a car you do not know, look inside the flap over your filler or at the cap before the first fill: plenty of motors state the fuel there.
- Mark the key. In a house with one of each, a coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember.
- "Diesel", out loud, before you lift the nozzle — every time a new or hired car needs its first tank. It seems silly. It does the trick.
- Mistakes like this are easy to make whilst your mind is on something else, so your phone goes away.
- Some diesels come with a filler designed to reject a petrol nozzle, and devices you can add exist for cars without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop checking the pump.
- As soon as you realise, stop: less petrol in your tank makes a thinner mixture. What to do next doesn't change, though — still don't fire it up.
Petrol already in a diesel around Wych? Start here
In that case, there is only a short order of things. Never fire it up, and do not turn your ignition on. Ask the attendants to help you push it clear of the petrol pump if you're still at the forecourt, whether that is Morrisons or somewhere else. What was put in, roughly how much, and if it's run: tell us that when you ring 0333 366 0103.
Say so if it was AdBlue rather than petrol: it's a separate fault, with its own page for Wych, since AdBlue brings corrosion and deposits rather than lost lubrication.
What makes one Wych petrol in a diesel job cost more than the next
The four scenarios above are four separate jobs, so no single price for this would be fair. The situation itself does most of the work of moving your cost. Beyond that it is the ratio — how much petrol was put in against how much that tank takes — and then where the car is and whether our van can reach it safely.
Before any quote, not after, come three questions: the fuel that went in, the amount, and if it has run. That is why. Their answers are what turn a range into one firm number.
About Wych itself
Wych is a small coastal suburban area in Dorset, situated near the towns of Bridport and West Bay. Wych sits at a low elevation of around 15 metres, close to the sea and near the villages of Bothenhampton and Skilling. Wych has a population of approximately 1137 people, predominantly living in detached houses. Wych is located within commuting distance of Exeter, which is around 34 miles away.
Across Dorset and in Wych: fuel drain cover
Bothenhampton, West Bay and Skilling are among the places near Wych that the same vans work, answering petrol in diesel calls across Wych's DT postcode area. 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.
In Wych and still at the petrol pump?
Then you're in the best spot there is. Leave the vehicle turned off, and ring.