How Worried Should You Be? Petrol in a Diesel Car in Helens Bay
Not started? Then less anxious than you probably are. Petrol sitting in a diesel tank does nothing to the motor until something pulls it through the fuel system — your ignition priming your pump, the starter, or the drive on its own. So the truthful answer to the first question everyone around Helens Bay asks, "have I ruined it?", is normally no. Petrol in Diesel is who to ring, with the engine kept off, so it remains that way. The remainder of this page explains what petrol actually 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.
Your engine and petrol in a diesel: what goes on
Passing through a motor, diesel is doing two jobs at the same time. Before it ignites, it lubricates — and then it ignites. What keeps the surfaces inside the high-pressure fuel pump and the fuel injectors from wearing against one another is the diesel passing through them — they're built to extremely fine tolerances.
Petrol handles the first task poorly and the second not at all. The rattling comes from petrol being made 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 out the lubrication the fuel system depends on, and any pump working on such a blend is wearing itself.
Taken together, they make clear the shape the issue takes. The harm is done by movement, not by contact. A tank with petrol in it is a fuel problem. A pump that has been working on that petrol is the start of a mechanical one, and whatever a worn pump sheds moves on with your fuel to the injectors downstream.
Petrol in a diesel around Helens Bay: how bad is it? Four cases
Fuelled but not once started — the best it gets. Only your tank has petrol in it, so the task is clearing the tank and rinsing the fuel system where the car stands. This situation can only truly occur at a forecourt: anywhere else, the car got there by being driven.
Started for a moment, or only your ignition on. Once primed, the fuel system has pulled petrol from your tank as far as the filter and the lines. Drain, flush, see to the filter: still usually easy.
Some miles driven, and the pump has spent every one of them running on thinned fuel. Miles is only half of that; how hard it was driven counts equally. Either way the work runs to the tank, your lines, the filter and clean fuel through the whole circuit. Driving the children to the local primary school is one sort of trip. Very different again: a trip to Belfast, under 10 miles away, or some mileage on the M77, over 50 miles from Helens Bay, where the engine kept working hard.
It protested, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone ragged. The engine is telling you the fuel is no longer behaving like diesel. Stop on the spot — on the verge on Heugh Road, at the kerb, down a side road — and don't move it again. The fuel drain and flush-through still go first, and they deal with it: when a vehicle is pulled over quickly, long-term damage is very unusual.
Stories Helens Bay people 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 mix is all you get, because topping up takes out nothing. The idea behind that advice — that diesel fuel systems accept petrol by percentage — is wrong.
"Newer diesels can handle a little petrol" — a myth, and closer to the reverse. At higher pressure, through smaller parts: that is how a current diesel handles its fuel, and so the protection counts more, not less.
"It starts, it drives, and so there is no harm" — the myth that trips up more people than any other. Diesel in a petrol motor normally leaves a motor that won't run: the driver stops, and so does the harm. Feed petrol to a diesel and it generally starts, ticks over and pulls away like nothing has happened — all the while its pump wears. A running engine doesn't mean fine.
Myth: "Add some two-stroke oil and drive the car home." It's an old workaround for a separate issue. None of what petrol thinned is put back by it — and later, your tank still contains that petrol.
The next start draws petrol back round your pump from your lines and the fuel filter, where some of that sits after your engine has been run. That's why draining your tank yourself does not sort it — a myth. It's also really dangerous to drain petrol into a can by the roadside.
Why petrol in a diesel occurs so easily
No one does it on purpose, and it's seldom carelessness. The petrol nozzle is the smaller of the two and slides into a diesel filler with almost no resistance; a diesel nozzle generally won't go into a petrol car at all. The forecourt makes it simple, and the slip runs one way.
Habit and the car getting out of step is how it happens. A new vehicle, a hire car or a courtesy car. Two motors on one driveway, one petrol, one diesel. A forecourt you know, but with its pumps laid out differently. A hurried fill on the way to the nearest station with a train to catch. Years of petrol motors behind you, a diesel Volkswagen Golf in front of you at the forecourt for its first tank — that is when. With rain, a call coming in, or children to deal with, your hand simply does what it has always done.
Helens Bay people: how to prevent petrol in a diesel next time
- Check the pump, not the colour. In the UK unleaded handles are normally green and diesel black, yet not on each forecourt. The label is what counts.
- The first fill in a strange car is the time to check your filler flap — on it, or on the cap, many motors state which fuel they take.
- Label your 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 intending to remember.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the petrol pump. It seems silly and it does the trick.
- Mistakes like this are easy to make whilst your mind is on something else, and so the phone goes away.
- A misfuel inhibitor helps, up to a point. Some diesels come with a filler built to block a petrol nozzle, and add-on devices are available for motors without one. They are a safety net, not a reason to stop reading the pump.
- Stop as soon as you notice. Less petrol in that tank means a thinner mix. It doesn't change what to do next, which is still not to start it.
Put petrol in a diesel in Helens Bay already?
Short and simple, then, is the order of things. Starting it is out, and so is turning on the ignition. Ask the attendants to help you roll it away from the pump if you are still on the forecourt, whether that is the nearest petrol station or somewhere else. Then call 0333 366 0103 and tell us what went in, roughly how much, and whether it's run.
Say so if it was AdBlue rather than petrol: it is a different issue, with its own page for Helens Bay, because AdBlue brings corrosion and deposits rather than lost protection.
Helens Bay petrol in a diesel jobs: why one costs more than another
There is no honest single price for this, since the four situations above are four separate jobs. What shifts the cost is chiefly which of them you're in. The share counts next, meaning how much of the tank is petrol, followed by the position of the vehicle and whether getting to it is safe for a van.
Ahead of any quote, not after, come three queries: the fuel that was put in, the quantity, and if it's run. That's why. Given the answers, you get a straight figure rather than a range.
About Helens Bay itself
Helens Bay is a coastal locality in County Down, situated near the towns of Crawfordsburn and Bangor, with Belfast approximately 9 miles to the west. Helens Bay sits at an elevation of around 35 metres, overlooking the Irish Sea. Helens Bay is characterised by its detached housing stock and quiet residential atmosphere, attracting those who want to live near the coast but within commuting distance of Belfast.
Helens Bay and County Down: where our fuel drain cover runs
Crawfordsburn, Bangor and Carrickfergus are among the spots around Helens Bay that the same teams work, answering petrol in diesel jobs across Helens Bay's BT postcode area. A forecourt, a supermarket car park, a lay-by or your own drive are all locations we work, and your vehicle does not need to come to us.
At the pump in Helens Bay, still?
The best spot there is, then — that's where you are. Switched off it remains; then call.