Petrol in a Diesel Car in Rochester: How Worried Should You Be?
Less than you probably are, if it hasn't been started. Until the ignition primes your pump, your starter cranks, or your car is driven, petrol in a diesel tank just sits there and does nothing. Which makes the honest reply to that first Rochester question — "have I ruined it?" — normally no. Petrol in Diesel is who to call, with your motor kept off, and so it remains that way. What petrol actually does to a diesel, how to gauge how far it has gone, and how to keep it from happening again: that is the rest of this page.
What petrol in a diesel does to the motor
Two tasks fall to diesel on its journey through a motor. Before it ignites, it lubricates — then it burns. Designed to extremely fine tolerances, your injectors and the pump rely on the diesel moving through them to stop their surfaces wearing against one another.
Petrol handles the first task badly and the second not at all. The knocking 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 runnier than diesel, it strips away the lubrication the fuel system depends on, and any pump working on that mixture is wearing itself.
The shape of the problem is plain when you put those together. It's movement that causes the harm, not contact. Where that petrol is only inside your tank, it is a fault of fuel, nothing more. A pump that has been working on that petrol is the beginning of a mechanical one, and whatever a worn pump sheds moves on with the fuel to your injectors further on.
How bad is petrol in a diesel? Four situations our engineers see around Rochester
Filled up, and never started: nothing beats it. On a forecourt, and genuinely only there, the petrol is still limited to that tank — since anywhere else your car was driven to reach it. The task is draining and purging on the spot.
Ignition on, or started for a second. Petrol has left your tank and reached the fuel filter and the lines, since your system has been primed. Normally little more than emptying, purging and seeing to the filter, and so still easy.
Those few miles driven were the pump working on fuel thinned by petrol the whole way. The work is that tank, the lines, the fuel filter and clean fuel through the entire system, and how hard the vehicle was driven matters as much as how far. Short trips, such as the school run to Rochester Riverside Church of England Primary School, are one thing. Driving as far as Southend-on-Sea, under 15 miles away, makes a very different job — as does any distance on the M2, under 3 miles from Rochester, with your engine working hard all the way.
Driven until it complained. Clattering, a ragged idle, smoke, a throttle that has gone soft. The engine is telling you your fuel is no longer acting like diesel. Stop wherever you are — the verge on Boley Hill, a lay-by, a side street — then leave it there. The fuel drain and flush still go first, and they sort it out: when a vehicle is pulled over early, lasting damage is very uncommon.
Rochester drivers and the petrol in a diesel stories they hear
It will not be fine. The myth: "Fill it the rest of the way with diesel and it will be." A fuller tank of the same mixture is all you get, because topping up removes nothing. A diesel fuel system does not accept petrol by percentage in the way that advice assumes.
If anything, the opposite is true. Myth: "A modern diesel can cope with a bit of petrol." Protection matters more on newer diesels, not less, because their fuel passes through more precise components at higher pressure.
This is the one that catches drivers. Myth: "If it starts and drives, there's no harm done." A petrol engine fed diesel normally won't run, so the driver stops and the harm stops with them. A diesel fed petrol usually starts, idles and drives away as though nothing has happened, while your pump grinds. Being able to run isn't the same as being fine.
Myth: "Add some two-stroke oil and drive the vehicle home." It's an outdated workaround for a distinct problem. That petrol is still in that tank after that, and whatever it has weakened isn't put back.
Once the engine has been run, part of the petrol is in the fuel filter and the fuel lines, not that tank — and the next start sends it straight back through the pump. So the myth "drain the tank yourself and you are sorted" doesn't hold. On top of that, petrol drained into a can by the road is truly risky.
How petrol ends up: petrol in a diesel
It's rarely carelessness, and nobody does it on purpose. A diesel nozzle mostly will not fit a petrol car, but the slimmer petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one error straightforward, and only in one direction.
Routine and the vehicle getting out of step is when it takes place. A car that's new to you — a hire car, on loan as a courtesy car, or brand new. A household with one petrol and one diesel on the drive. The pumps in a different order on a familiar forecourt. Racing for a train at the nearest station and fuelling up en route. A new-to-you diesel Renault Clio, its first fuelling, and a driver used to petrol: exactly when it occurs. Your hand does what it has always done when you add rain, a phone call or a back seat full of kids.
Next time you fill up around Rochester: preventing petrol in a diesel
- The label is what matters, so read the petrol pump instead of the colour: in the UK unleaded handles are normally green and diesel black, yet not on each forecourt.
- Plenty of vehicles state the fuel inside the filler flap or on the cap, so check there on the first fill in a car 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 intending to remember.
- "Diesel", out loud, before you lift the nozzle — every time a new or hired car gets its first tank. It seems silly. It does the trick.
- Mistakes like this are easy to make while your mind is on something else, and so your phone goes away.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler designed to refuse a petrol nozzle, and aftermarket devices exist for the remainder. Treat it as a backstop, then keep checking the pump.
- Less petrol means a weaker mix, and so stop as soon as you realise — though remembering that your next stage is unchanged. It's still not to fire it up.
Petrol already in a diesel in Rochester? Begin here
Then, there is only a short order of things. Never fire it up, and do not turn your ignition on. The attendants at the forecourt — whether at Texaco itself or wherever you filled up — will usually help push it away from the pump if you ask. Then phone 0333 366 0103 and tell us what was put in, about how much, and if it has run.
AdBlue, not petrol? Then say so. Corrosion and deposits, not lost lubrication, make it a separate fault — Rochester has a page all for it.
One petrol in a diesel job around Rochester costs more than another. Why?
There is no honest single quote for this, since the four scenarios above are four separate jobs. Which of them you're in is chiefly what moves your cost. Where the vehicle is counts too, and whether our van can safely reach it, after the share of petrol to what that tank holds.
That's why we ask three questions before costing rather than after: what got in, how much, and if it's run. A range becomes a straight figure when those replies are in.
About Rochester itself
Rochester is a town situated on the coast of Kent, where the River Medway meets the sea. Located near the mouth of the river, it is part of a larger urban area that includes several neighbouring towns. Rochester has a significant history and was once a city, although it lost this status in the late 20th century. The town is close to London, making it an important location in the southeast of England.
Fuel drain cover across Kent, Rochester included
Troy Town, Strood and Frindsbury are among the locations around Rochester that the same vans work, answering petrol in diesel jobs across Rochester's ME postcode area. We drain where the car is — your own drive, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
At the petrol pump around Rochester, right now?
No position is better: that's where you are. Keep the vehicle turned off, and ring.