How Worried Should You Be? Petrol in a Diesel Car in Milton
Likely less than you are now — provided nobody has started it. Everyone in Milton begins with "have I ruined it?", and the honest answer is normally no: petrol resting in that tank of any diesel remains harmless until priming, cranking or driving draws it into your fuel system. To keep it that way, phone Petrol in Diesel then leave your engine switched off. The remainder of this page sets out what petrol actually does to a diesel, how to tell how far it has got, and how to make sure it doesn't happen to you again.
What petrol in a diesel does to the motor
Diesel does two jobs on its way through an engine. Before it ignites, it protects — then it ignites. The high-pressure fuel pump and your injectors are designed to very fine gaps, and the diesel passing through them is what keeps those surfaces from grinding against one another.
The second task petrol doesn't do at all, and the first it does poorly. 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 thinner than diesel, it strips away the protection the system depends on, and any pump running on that blend is wearing itself.
Put these together and the shape of the problem is clear. It is circulation that does the damage, not contact. All a tank with petrol in it amounts to is a fuel fault. Once the pump has been working on that petrol, a mechanical fault has begun: anything shed by a pump that's wearing down travels downstream to the injectors with your fuel.
Four situations our technicians see in Milton: how bad is petrol in a diesel?
Filled up, and not started: no case is better. Being at a forecourt is what makes this the case: elsewhere, your car has been driven there to begin with. With the petrol held in the tank alone, it is cleared and cleaned right where it stands, and nothing more is needed.
A brief spell of running, or just the ignition on. Your system has been bled, so petrol has left that tank and reached the filter and the lines. Drain, flush, see to your filter: still normally straightforward.
Driven a few miles. Now the pump has spent these miles working on weakened fuel. The work is the tank, the lines, your filter and clean fuel through the entire circuit, and how hard the vehicle was driven matters as much as how far. The school run to Chantry Community Primary School is one thing. Any mileage on the M2, under 5 miles from Milton, means the motor working hard throughout, and a run to Southend-on-Sea, under 25 miles away, is a very different job as well.
Driven until it protested. Rattling, an uneven idle, smoke, a throttle that has gone soft. That's the engine telling you its fuel no longer is behaving like diesel. Leave it wherever it stops: a lay-by, a side street, the verge on Ordnance Road. What goes first is still the drain and flush-through, and that sorts it out, with long-term damage very unusual when a car is stopped soon.
Myths Milton drivers hear about petrol in a diesel
"Top it up the rest of the way with diesel and it will be fine" — a myth. It will not. Topping up removes nothing; it gives you a fuller tank of the same mixture. That advice presumes a diesel fuel system tolerates petrol by percentage. It does not.
Myth: a newer diesel copes with a bit of petrol. If anything, the reverse. Protection counts more on current diesels, not less, since their fuel runs through smaller parts at higher pressure.
"It starts, it drives, so there is no harm" — the myth that trips up most motorists than any other. Diesel in a petrol motor normally means a motor that will not run: the driver stops, and so does the damage. A diesel fed petrol generally starts, ticks over and drives away as if nothing has happened, while your pump grinds. A running engine doesn't mean fine.
Myth: "Add some two-stroke oil and drive the vehicle home." It is an old fix for a distinct problem. The petrol is still in your tank afterwards, and whatever it has diluted isn't put back.
Myth: "Drain that tank yourself and you're sorted." Once the motor has been run, some of that petrol is no longer in the tank: it is in your filter and your lines, and it goes straight back through your pump at your next start. Also, a can of petrol filled at the roadside is truly hazardous.
Why petrol in a diesel happens at all
It is rarely carelessness, and nobody does it on purpose. One way only, since of the nozzles: the smaller petrol one slides inside a diesel filler with almost no resistance, whereas the diesel one mostly will not fit a petrol vehicle. That's how the forecourt makes it straightforward.
Routine and the car falling out of step is how it happens. Courtesy car, hire car, or a vehicle that's brand new. A household with one petrol and one diesel on the drive. A forecourt you know, but with its pumps arranged differently. A train to catch, and a hurried fill on the way to Gravesend. Years of petrol vehicles behind you, a diesel Renault Clio in front of you at the forecourt for its first tank — that is when. Add a back seat full of children, a phone call or rain, and habit wins.
Next time you fill up around Milton: avoiding petrol in a diesel
- Check the petrol pump, not the colour. In the UK unleaded handles are generally green and diesel black, yet not on each forecourt. The label is what counts.
- The first fill in a strange vehicle is the time to check your filler flap — on it, or on the cap, many motors state the fuel they take.
- Mark the key. In a house with one of each, a coloured fob or a sticker on the diesel's key does more than any amount of intending to remember.
- It sounds silly and it works: on your first fill in a new or hired car, say "diesel" aloud before you lift the nozzle off the petrol pump.
- While you're thinking about something else, this is an easy mistake to make — so put the phone 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 exist for cars without one. They are a backstop, not a reason to stop reading the pump.
- Stop as soon as you realise. Less petrol inside the tank makes a weaker mix. It does not change what to do next, which is still not to start the car.
Milton: already put petrol in a diesel?
Then the order of things is brief. Do not crank it, and don't switch your ignition on. If you're still at the forecourt — Esso or anywhere else — ask the staff to help you push the vehicle away from the petrol pump. Then ring 0333 366 0103 and tell us what went in, roughly how much, and whether it has run.
Corrosion and deposits form the trouble with AdBlue, whereas petrol means lost lubrication. So if it was AdBlue, say so — and see its own Milton page.
Why one petrol in a diesel task in Milton costs more than another
The four situations above are four different jobs, so no single quote for this would be honest. Chiefly, your cost shifts with which situation you are in. The proportion counts next, meaning how much of that tank is petrol, followed by the location of the car and whether getting to it is safe for our van.
Three questions come first, before quoting, instead of after — what got in, how much, has it run — and that is the reason. The answers turn a range into a straight figure.
About Milton
Milton is a coastal suburban area in Kent, situated near the towns of Gravesend and Southend-on-Sea. Milton lies at a low elevation of around 9 metres, close to the Thames estuary. Milton is characterized by its predominantly flat housing stock, which reflects its development as a residential area. Milton is also near to other local places such as Windmill Hill and Denton.
Fuel drain cover across Kent, Milton included
Petrol in diesel call-outs in Milton — part of the DA postcode area — go to teams that also cover the locations round it, Gravesend, Windmill Hill and Denton included. We drain wherever your car is — your own drive, a lay-by, a supermarket car park, a forecourt — so it never needs to come to us.
Still at the petrol pump around Milton?
Then you're in the best position there can be. Phone, and leave it turned off.