Should You Worry? Petrol in a Diesel Car in Rattery
Far less than you likely are, if it has not been started. Everyone around Rattery starts with "have I wrecked it?", and the honest answer is usually no: petrol left in the tank of any diesel stays harmless till priming, cranking or driving draws it into the fuel system. Leave your engine off and phone Petrol in Diesel — that is how you keep it like that. What petrol actually does to a diesel, how to judge how far it's gone, and how to keep it from happening again: that's the rest of this page.
Petrol in a diesel: what does it do to the engine?
Diesel does two jobs on its way through a motor. Lubricating comes before burning; it does both. The high-pressure fuel pump and the fuel injectors are built to extremely fine gaps, and your diesel passing through them is what keeps those surfaces from wearing against one another.
Of these two jobs, petrol handles the first poorly and the second not at all. The knocking comes from petrol being made not to ignite when compressed, which is exactly the opposite of what a diesel needs. On top of that it is runnier than diesel, it strips out the protection your system hinges on, and any pump working on that mix is wearing itself.
Together, those make the shape of the issue clear. Not contact but circulation is what causes the harm. All a tank with petrol in it amounts to is a fuel issue. A pump that has been running on that petrol is the start of a mechanical one, and whatever a worn pump sheds moves on with your fuel to your injectors further on.
Petrol in a diesel around Rattery: how bad is it? Four cases
Fuelled, and not started: nothing beats it. The petrol is inside that tank and just the tank, and the job is a drain and a flush where your car sits. This is the one scenario that can only truly happen on a forecourt, because anywhere else your car has been driven to get there.
Ignition on, or started for a second. With your system primed, the fuel lines and filter already hold petrol that came from the tank. Drain, flush, deal with the filter: still usually easy.
A couple of miles driven, and the pump has spent each of them labouring on weakened fuel. Distance is only half of it; how hard it was driven counts equally. Either way the work includes that tank, your lines, your filter and clean fuel through the entire system. Short trips, such as the school run to South Brent Primary School, are one matter. A run as far as Plymouth, under 25 miles away, is a very different job. So is any mileage on the M5, under 25 miles from Rattery, where the engine has been running hard the whole time.
Driven on till it complained — clattering, smoke, an uneven idle, a soft throttle. What you are hearing is your engine reporting fuel that no longer behaves like diesel. Pull up where you are — on the verge on Garden Close, at the kerb, down a side road — and don't move it. The fuel drain and flush-through still go first, and they sort it out: if a car is stopped early, permanent damage is very unusual.
Stories Rattery people hear about petrol in a diesel
Myth: "Fill it the rest of the way with diesel and it'll be fine." It will not. Nothing comes out when you top up — the tank simply holds more of the same blend. Percentage isn't how a diesel fuel system tolerates petrol, however much that guidance assumes.
Myth: "A current diesel can cope with a bit of petrol." If anything, the opposite. More precise components and higher pressure are the way a modern diesel runs its fuel, and that makes the protection matter more, not less.
This is the one that catches people. Myth: "If it starts and drives, there's no harm done." The motorist of a petrol engine fed diesel normally has no choice but to stop, because it will not run, and the harm stops with them. A diesel fed petrol generally starts, ticks over and drives away as though nothing has happened, whilst the pump wears. A running engine doesn't mean fine.
"A drop of two-stroke oil and drive it home" — a myth, taken from a fix from years ago, for a separate issue. It doesn't put back what petrol has diluted, and that petrol is still in your tank later on.
"Drain it yourself and you're sorted" — a myth, since after it has been running some petrol sits in the filter and lines, ready to go straight back through your pump at the next start. Besides, petrol emptied into a can by the road is genuinely hazardous.
Why petrol in a diesel happens so easily
A careless moment is seldom the cause, and no one means to do it. The petrol nozzle is the narrower of the two and slides into a diesel filler with almost no resistance; a diesel nozzle mostly won't go into a petrol vehicle at all. The forecourt makes it simple, and the mistake runs one way.
The moment routine stops matching the car is the moment it occurs. Any car that's new to you — hired, on loan as a courtesy car, or brand new. Two cars on one drive, one petrol, one diesel. A familiar forecourt with the pumps in a different order. Racing for a train at Totnes and filling up en route. Precisely the moment it occurs: after years of driving petrol, a driver fills a diesel Renault Clio for the first time. Add a back seat full of kids, a phone call or rain, and habit takes over.
Rattery drivers: 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. Trust the label on the pump, not the colour.
- Many cars state the fuel type inside your filler flap or on the cap, and so check there on your first fill in any motor you do not know.
- Good intentions count for less than a sticker or a fob in a bright colour on the diesel's key if a household has one of each. So mark it.
- "Diesel", out loud, before you lift the nozzle — every time a new or hired car needs its first tank. It sounds daft. It works.
- Thinking about something else is when this becomes an easy mistake to make, so put your phone away then keep your mind on the pump.
- A misfuel inhibitor helps, up to a point. Some diesels have a filler built to refuse a petrol nozzle, and add-on devices are available for cars without one. They are a safety net, not a reason to stop checking the pump.
- Less petrol means a weaker mix, so stop the moment you realise — while remembering that the next step is unchanged. It is still not to crank it.
Put petrol in a diesel in Rattery already?
Short and simple, then, is the order of things. Don't switch your ignition on, and do not crank it. Still on the forecourt, at Blue Post Garage or anywhere else? Ask the attendants to help you push it clear of the petrol pump. Then call 0333 366 0103 and tell us what got in, about how much, and whether it's run.
Say so if it was AdBlue rather than petrol: it's a separate problem, with its own page for Rattery, because AdBlue brings corrosion and deposits instead of lost lubrication.
What makes one Rattery petrol in a diesel task cost more than the next
A fair single price does not exist here: four scenarios, four separate tasks. Mostly, the cost moves with which situation you are in. Two things follow that: the petrol that went in as a share of what the tank takes, then the place 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 amount, and if it has run. That is why. Their replies are what change a range into one firm number.
About Rattery itself
Rattery is a small village in Devon, situated on the banks of a river in the South West of England. Rattery sits at an elevation of 119 metres, surrounded by rolling countryside and nearby villages such as Culverlane and Brownston. Rattery is characterized by its predominantly detached housing stock and remains a quiet residential community. Rattery is located approximately 16.9 miles from Plymouth and 174.9 miles from London.
Fuel drain cover across Devon, Rattery included
Petrol in diesel jobs in Rattery — part of the TQ postcode area — go to vans that also cover the locations round it, Culverlane, Brownston and Dean Prior among them. A forecourt, a supermarket car park, a lay-by or your own driveway are all places our engineers work, and the car doesn't need to move to us.
Still at the petrol pump in Rattery?
Then you're in the best position there is. Phone, and keep it switched off.