Should You Worry? Petrol in a Diesel Car in Plumstead
Unstarted? Then less anxious than you probably feel. Petrol resting in a diesel tank does nothing to the motor until something draws it through the fuel system — your ignition priming the pump, your starter, or the drive itself. So the fair answer to the first query everyone around Plumstead asks, "have I wrecked it?", is usually no. Petrol in Diesel is who to call, with the engine left off, so it stays that way. Keep reading for three things: the effect petrol has inside a diesel motor, the clues of how far it has got, and ways to make sure you never repeat it.
Petrol in a diesel: what does it do to your engine?
On its way through an engine, diesel does two tasks. It ignites, and before it burns it lubricates. Your high-pressure pump and the fuel injectors are designed to extremely fine clearances, and the diesel passing through them is what stops those surfaces from wearing against each other.
Of those two jobs, petrol manages the first badly and the second never. Being less viscous than diesel, petrol strips out the lubrication a fuel system needs, leaving a pump on that mixture wearing itself. It's equally made to resist igniting under compression — the reverse of what a diesel needs — which is where you hear the knocking.
Put these together and the shape of the issue is clear. Contact does not do the damage — circulation does. Any tank with petrol in it is a fuel problem. The start of a mechanical one is a pump that has been running on that petrol — and whatever a worn pump sheds moves on with your fuel to your injectors beyond it.
Petrol in a diesel around Plumstead: how bad is it? Four situations
Filled up, never started. The best case there is. At a forecourt, and truly only there, that petrol is still limited to that tank — since anywhere else the car was driven to get to it. The job is draining and cleaning on the spot.
Ignition on, or started for a moment. Once primed, the fuel system has drawn petrol from the tank up to the filter and the fuel lines. That's usually still a simple job — a drain, a flush, and the fuel filter dealt with.
Driven a few miles. Now your pump has spent those miles labouring on weakened fuel. Tank, lines, filter, then fresh fuel put through the whole system: that's the work, and the way your car was driven counts as much as the distance. Short trips, like the school run to St Margaret's Church of England Primary School, are one matter. Getting as far as London, under 10 miles away, makes a very different task — as does any miles on the M11, under 10 miles from Plumstead, with your engine working hard the whole time.
Driven on until it protested — clattering, smoke, an uneven idle, a dead throttle. What you are hearing is the motor reporting fuel that no longer acts like diesel. Stop where you are — on the verge on Kirk Lane, at the kerb, down a side road — and don't move it. The fuel drain and flush-through still go first, and they deal with it: if a car is stopped soon, long-term damage is very unusual.
What Plumstead people get told about petrol in a diesel — and the myths in it
False: topping up to full with diesel makes it fine. It doesn't. Nothing is removed by topping up — you're left with a fuller tank, still the same mix. That advice presumes a diesel fuel system tolerates petrol by percentage. It doesn't.
Myth: "A current diesel can cope with a bit of petrol." If anything, the opposite. Lubrication counts more on modern diesels, not less, since their fuel passes through smaller parts at higher pressure.
"It starts, it drives, so no harm done" — the myth that trips up most motorists than any other. Diesel in a petrol motor normally leaves a motor that won't run: the motorist stops, and so does the harm. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually will; meanwhile your pump grinds. A running engine does not mean fine.
Not so: a two-stroke additive lets you to drive home. It was an old fix, meant for another problem. None of what petrol thinned gets put back by it — and afterwards, your tank still contains the petrol.
Myth: "Drain the tank yourself and you are sorted." Once the motor has run, some of that petrol is no longer inside the tank: it is in your filter and the lines, and it goes straight back through your pump at your next start. It is also truly risky to drain petrol into a can at the kerbside.
Why petrol in a diesel happens at all
On purpose? Never. Through carelessness? Rarely, if ever. The petrol nozzle is the narrower of the two and slides into a diesel filler with almost no resistance; a diesel nozzle mostly will not go into a petrol motor at all. The forecourt makes it easy, and the error runs one way.
Routine and the car getting out of step is how it happens. A car that is new to you — a hire car, on loan as a courtesy car, or just bought. One petrol and one diesel on the drive of the same household. A forecourt you know, but with its pumps arranged differently. A rushed fill en route to the nearest station with a train to catch. Years of petrol vehicles behind you, a diesel Renault Megane in front of you at the forecourt for its first tank — that is when. Throw in a back seat full of kids, a phone call or rain, and habit takes over.
Next time you fill up in Plumstead: avoiding petrol in a diesel
- Not every forecourt in the UK follows green for unleaded and black for diesel, though most generally do. Check the pump's label; the colour is only a clue.
- Many cars state the fuel inside your filler flap or on the cap, and so check it on the first fill in any motor you don't know.
- A coloured fob or a sticker on your diesel's key does more than any amount of meaning to remember, for a home with one of each.
- "Diesel", aloud, before you pick up the nozzle — every time a new or hired car needs its first tank. It sounds silly. It does the trick.
- Mistakes like this are straightforward to make whilst your mind is on something else, so your phone goes away.
- Up to a point, a misfuel inhibitor helps: some diesels come with a filler built to reject a petrol nozzle, and add-on devices exist for the remainder. Treat it as a backstop, and keep checking the petrol pump.
- The moment you realise, stop: less petrol in the tank makes a weaker blend. What to do next doesn't change, though — still do not crank it.
Already put petrol in a diesel in Plumstead?
Then the order of things is brief. Do not switch your ignition on, and do not fire it up. The attendants at the forecourt — whether at Shell itself or wherever you filled up — will usually help push it clear of the pump if you ask. What went in, roughly how much, and whether it has run: tell us that when you phone 0333 366 0103.
Corrosion and deposits form the problem with AdBlue, whereas petrol brings lost lubrication. So if it was AdBlue, say so — and read its own Plumstead page.
One petrol in a diesel task around Plumstead costs more than another. Why?
There is no honest single quote for this, since the four situations above are four different tasks. Which of them you are in is mostly what shifts the cost. Next it is the proportion — how much petrol was put in against how much the tank takes — and then where your car is and whether a technician can reach it safely.
Three questions come first, before quoting, rather than after — what was put in, how much, has it run — and this is the reason. Given those answers, there is a straight figure rather than a range.
About Plumstead, for a moment
Plumstead is a suburban area in southeast London, situated approximately 9 miles from central London and 57 metres above sea level. Plumstead is characterized by its predominantly terraced housing stock and is located near Plumstead Common and the Royal Arsenal West development. Plumstead has a population of around 18,468 residents and is close to the nearby town of Woolwich. Plumstead is also near the River Thames, which has played a significant role in the area's development.
Plumstead and Greater London: where our fuel drain cover runs
Plumstead Common, Royal Arsenal West and Woolwich are among the places around Plumstead that the same vans work, answering petrol in diesel call-outs across Plumstead's SE postcode area. A forecourt, a supermarket car park, a lay-by or your own drive are all places we drain, and your vehicle does not need to move to us.
At the petrol pump around Plumstead, still?
Then you're in the best position there is. Keep it turned off, then ring.