--- title: AdBlue in a Diesel Tank Long Cross — Don't Start It canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/long-cross-somerset/ location: Long Cross county: Somerset latitude: 51.386290 longitude: -2.680910 service: AdBlue in a Diesel Tank updated: 2026-10-19 --- # AdBlue in the Diesel Tank in Long Cross? Keep It Switched Off Engine off, ignition off: that is where you begin if AdBlue has gone into the diesel tank. Urea dissolved in water is all AdBlue is. Being water-based, it will not ignite and never combines with diesel; damage only starts when your pump begins drawing it. Caught before the motor has run, AdBlue in a diesel tank is generally a drain and a thorough flush, done where the vehicle is in Long Cross. Before anything, phone us on 0333 366 0103. ## Those opening minutes: AdBlue in the diesel tank around Long Cross Things to do: - Pocket the keys, and that prevents anyone switching the power on. - Put the hazards on if you are at all close to moving traffic. - Keep the till receipt or the empty bottle, so you can tell us what went in and roughly how much. - Tell us a postcode starting BS40 9, or whichever street is nearest, and the van finds you straight — so call wherever you stand. Do not do these: - No starting your engine — not for a second, not to shift your car. - Your ignition stays off: on many diesels, turning it on is enough to start your fuel pump. - AdBlue does not dilute in diesel — it separates out — so adding extra diesel will not weaken it. - Never drive the car anywhere, not even a short way up Vee Lane. - By the road, don't attempt draining it yourself. The staff on duty at any Long Cross forecourt — the the nearest petrol station among them — will normally lend a hand rolling it clear if you ask. At home, the vehicle stays exactly where it is. ## AdBlue in a diesel tank, and what it does there The motor isn't what AdBlue is made for; the exhaust is. From a separate reservoir it is fed straight to your exhaust, cleaning what your motor emits. A fuel pump isn't made to take it, and AdBlue was never supposed to go through one. It doesn't blend. Once it is poured into the tank, AdBlue acts not at all like fuel. It is heavier than diesel, so it sinks and collects at the bottom of the tank, which is where the pickup draws fuel from. The first thing the system pulls through, once it runs, is the AdBlue. So a car that had AdBlue poured in on a drive in Winford last night, and has not been started since, is still the straightforward case: the AdBlue is lying at the bottom of the tank, and nothing has drawn it in. From there it causes two kinds of harm. Crystals and corrosion. As the water evaporates, it leaves urea that hardens in filters and tiny channels; meanwhile, since it attacks some metals, every part it touches suffers for as long as it remains inside. A motor left standing in Long Cross with AdBlue already in its lines is worse by the morning; one with AdBlue just in its tank isn't. Water lubricates nothing. The injection pump and each injector depend on diesel flowing past them, and so the water content harms them in its own right. ## Why AdBlue in a diesel is frequently more significant than petrol Fill a diesel with petrol in error over at the Shell, and this problem is thinned fuel. It mixes with the diesel, and whilst it is inside that tank it causes no harm; the damage comes from running your motor on it. AdBlue in a diesel is another matter: not thin fuel, but no fuel at all. It doesn't burn, so it cannot just be run through. It doesn't stay mixed, so it cannot be diluted. And crystals and corrosion do not wash out with the next tank of fuel. That is why the flush counts more with AdBlue than with petrol, and why starting the engine "to see" costs more here than almost anywhere else, whether the car is in Lulsgate Bottom or the middle of Long Cross. As with petrol, there is good news. Never run? Then the AdBlue waits just inside the tank, the simplest bit of the entire system to empty, anywhere your vehicle has stopped around Somerset. ## Long Cross: how AdBlue ends up in a diesel tank After dark, two caps together — the AdBlue one and the diesel cap, now and then under one flap — can appear the same. No one means it; plenty of designs invite it. It usually takes place at home, from a bottle bought en route home, not at the forecourt. Mostly, it occurs in one of a couple of familiar ways. Midway through the drop-off, the dashboard flags it up, and outside Winford Church of England Primary School the refill is rushed. A bottle is poured in at the end of the day on a drive just off Upper Town Lane. Otherwise, in dim light by George and Dragon, the car gets refilled by someone using that flap for the first time. It comes up the most in a hire car, a brand-new vehicle, a company vehicle, or the other vehicle in a family with one of each fuel types — the vehicles people know the least. Anywhere around Somerset, Long Cross as well, the mistake does not change, and neither does the first response: keep it switched off. ## Already started the motor with AdBlue in your diesel tank in Long Cross? The AdBlue has left that tank, then. It has been sucked through your filter and your lines, and if the motor ran for any time, it has reached your high-pressure pump and the injectors. Watch for rough running, smoke, falling power, lights on the dash, or a cut-out — returning from Felton Common, say, or midway across Long Cross. Stop as soon as it is safe, switch off, and don't restart it to check. More of that is pulled through with each start. Exit the M5, under 10 miles from Long Cross, by the next junction and park safely, rather than driving on. Mileage counts: each mile carries the AdBlue further in, so heading for Bristol, under 10 miles away, gives a much larger job than hopping across Long Cross to the car park by tumulus. Approximately how far had it come? Tell us. Wherever the vehicle came to a stop is where all of it gets done, even with more to rinse out once the motor has been run. Very rarely does it leave long-term damage when it's noticed quickly. ## Clearing AdBlue in a diesel in Long Cross: what it takes Anywhere it has stopped around Long Cross — a forecourt, a lay-by, a drive, a street beside Hartcliff Rocks — the van travels to the car. Before anything else our technicians ask what went in, roughly how much, and whether the motor has run, since those replies settle the work. Then that tank is cleared where the car stands, and so the tainted fuel and the AdBlue come out together. With AdBlue, more so than with petrol, the flush matters: the whole system is flushed all the way through since residue won't wash away by itself. Next, your filter: flushed, or changed when it must be. After that fresh diesel, then a test of your car. If the engine has not run, most jobs take about half an hour once our engineers arrive. The pumping gear is explosion-proof, so a live filling station is no issue, and it is hushed enough for a residential street late at night. Finally, the system is primed with clean diesel. You head off as soon as our technicians have started the car, and it makes no difference whether the car is on a drive around Long Cross or in a bay by Nailsea & Backwell. The test before our technicians head off is that it runs correctly on new diesel. The whole job is done where your car is, so it never has to be taken to a workshop. Your insurer is likely to want an engineer's report and your VAT invoice — both yours afterwards. ## About Long Cross itself Long Cross is a suburban area located inland in Somerset, with an elevation of around 148 metres, and is situated approximately 5.8 miles from Bristol. Long Cross is characterized by its predominantly detached housing stock and is close to nearby places such as Felton, Potters Hill, and Kingdown. Long Cross has a relatively small population of around 694 residents. Long Cross is also within commuting distance to larger cities, with London being around 110.3 miles away. ## AdBlue drains across Somerset, Long Cross included The teams that answer AdBlue call-outs around Long Cross also cover the spots round it, Felton, Potters Hill and Kingdown among them, and most of Somerset beyond, across the BS postcode area. If you're close to a border, or somewhere hard to explain, ring and ask rather than assuming. No towing is needed. In Long Cross, a residential suburb, a van that comes to you works: the vehicle is drained where it stands, whether in a driveway, a side street, a car park or a forecourt. ## Long Cross: what AdBlue in a diesel tank costs to fix Since the jobs differ, a single price wouldn't be honest. What shifts the price is, firstly, whether the engine has run and for how long; then how much AdBlue went in; and then where your car is and whether our van can get to it safely, which is easier on an open drive than in a tight spot behind Saint Katherine's Church. What was put in, how much, plus whether it ran: each Long Cross enquiry begins by asking precisely that, ahead of any figure, not after. Once they are known, a range turns into a single firm number. Before anyone sets off, you hear our price on the phone. Then payment is on the day, card or by phone, with nothing upfront. Check your insurance while we are on the way: plenty include misfuelling cover. ## Long Cross: still beside the vehicle? Then, the most helpful thing to do with your car is to not touch it. Keys out, motor off, ignition off. Say it's AdBlue, roughly how big an amount, and whether the engine ran, on 0333 366 0103. After that Petrol in Diesel takes over, across Long Cross or wherever within Somerset.