--- title: Mexborough: AdBlue in a Diesel Tank, Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/mexborough-south-yorkshire/ location: Mexborough county: South Yorkshire latitude: 53.494210 longitude: -1.294160 service: AdBlue in a Diesel Tank updated: 2026-10-15 --- # Mexborough: How Does AdBlue End Up in a Diesel Tank, and How Do You Prevent It? If AdBlue is already in your diesel tank, stop reading for a moment: leave the motor and the ignition off then phone 0333 366 0103. A drain and a thorough flush, done just where your car sits in Mexborough, is usually all it takes if caught before the motor runs. If you're reading before it has happened, the remainder of this page is about why it takes place and how to make sure it doesn't. ## AdBlue in a diesel vehicle: two tanks, two fillers No single fluid but two: that's how many newer diesels around Mexborough and Bow Broom run, with diesel feeding your engine. Stored in a tank of its own, AdBlue is sprayed into your exhaust stream to clean it. Different tanks, separate fillers. Other vehicles put the AdBlue filler in your boot or under the bonnet; a lot more place the two side by side behind one flap. Filling your diesel side at the petrol pump goes on all the time. The AdBlue side is fuelled far less commonly, usually from a bottle, and normally by someone who has to stop and think where it goes. That gap is where the slip lives. ## AdBlue in your diesel tank around Mexborough: how it happens It's rarely carelessness. Three things tend to line up. Haste comes from the warning. The vehicle warns you as AdBlue runs low, and a dry tank sends the vehicle into limp mode — so the top-up gets done quickly, before work on a drive off Hartley Street, or on the way home in the car park at The Falcon. The old car's cap is where the hand goes — yet a hire car, a new vehicle or a company car keeps the fillers somewhere else. That is a second thing: a strange car. Nothing halts the pour once it has started, since a bottle with a spout goes into a diesel filler as readily as an AdBlue one. The bottle fits. Dolcliffe Common or the heart of Mexborough: it takes the same few seconds either way. ## How to tell the AdBlue filler from the diesel one Before you pour anything, whether on a drive in Old Denaby or a forecourt around Mexborough, check these. They take a couple of seconds. - The cap. The AdBlue cap is regularly blue, or marked "AdBlue". The diesel cap normally is not. Read it instead of going by where it sits. - The size. On many motors the AdBlue filler neck is the smaller of the two. - Check inside the fuel flap: many vehicles carry a label there saying which fuel goes where. - The handbook shows which it is if the filler is not next to your diesel cap: your boot, or under the bonnet. - Collecting a hire or company car, perhaps at the car park outside the nearest station? Check with whoever drove the vehicle last before you set off, rather than when the light comes on. ## Keeping AdBlue out of your diesel tank when you top up Anywhere around South Yorkshire the light comes on, this is a routine for the day. - Park and switch off. Not on a slope, not with the engine running, and not in a rush on the side of Main Street. - Find the AdBlue filler and read the cap. Say "AdBlue" out loud as you unscrew it. It sounds daft and it does the trick. - The diesel cap stays on. Where the two sit under a flap, make sure it is closed before the bottle comes up. - Gently does it, through the bottle's own spout, until it is full or the bottle is empty. - Close the cap and check a second time. Make sure your diesel cap was never opened. Only then start the car. Spot at step two or three that it has already gone into your diesel side? Then stop just there. Skip stage five entirely. ## Already put AdBlue in the diesel tank in Mexborough? The short order of things, beginning with no starting your motor. The fuel pump starts on plenty of diesels the moment the ignition goes on — so leave it off. Topping up with diesel won't weaken it: rather than mixing, AdBlue drops to the base of that tank, just where the fuel is taken from. Ask the staff to help push the car away from the petrol pump if you are at a forecourt — the JET, the TotalEnergies or anywhere else. Your own driveway around Mexborough is where it stays. Where the motor has run by now, stop safely then turn it off. On the M18, under 5 miles from Mexborough, that means the next exit. A short hop across Mexborough is a smaller job than a run towards Doncaster, under 10 miles away, so tell us roughly how far it went. ## Mexborough: what occurs when we arrive By Montagu Academy, near Mexborough Library or on your own driveway: wherever the car has stopped, our engineers come to it. Our technicians ask what went in, about how much, and whether it has run, because those replies decide this work and our quote. No one heads out until you've had the quote by phone. Draining your tank comes next, followed by a full flush of the system. Unlike petrol, AdBlue leaves crystals and attacks some fuel-system metals, and none of it clears out unaided. That is why it matters more. After your filter is flushed — or replaced, if required — clean diesel is added, and then the car gets tested. We don't go until it has been fired up and is running correctly. With pumps safe on a working forecourt and quiet enough to use outside a house at night, most jobs in which the motor hasn't run need about half an hour once we are there. Paying happens on the day, not upfront, and you are given the documents your insurer asks for: an engineer's report and a VAT invoice. While we travel, take a look at your insurance documents; plenty include cover for misfuelling. ## About Mexborough Mexborough is a town in South Yorkshire, situated on the banks of the River Don at an elevation of around 24 metres. Mexborough lies approximately 6.9 miles from Doncaster and 145.8 miles from London, with nearby areas including Dolcliffe Common and Swinton Bridge. Mexborough has a population of around 15968 people, predominantly living in semi-detached housing. Mexborough is characterized by its riverside setting and surrounding landscape. ## Mexborough and South Yorkshire: AdBlue drains across the area Mexborough is a riverside town, and our vans that cover it also work the places near it, Swinton Bridge and Highwoods among them, across the S postcode area. Give a postcode beginning S64 9, and our van arrives quickest. There's no need to move the car. Anywhere it sits — near Mexborough Market, on a layby heading to Peas Hills Plantation, at home — that's where it gets cleared. Ring and ask rather than guessing if you are near a border, or somewhere hard to explain, like the back of Mexborough Children's Centre. ## The short version for Mexborough people First, the cap; after that, the pour. AdBlue in the diesel tank after all? Leave the vehicle off then ring 0333 366 0103; Petrol in Diesel drains it on the spot, across South Yorkshire.