--- title: AdBlue in a Diesel Tank Watchet? Read This canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/watchet-somerset/ location: Watchet county: Somerset latitude: 51.182050 longitude: -3.330550 service: AdBlue in a Diesel Tank updated: 2026-10-22 --- # AdBlue in a Diesel Tank in Watchet: How It Occurs and How to Stop It AdBlue already in the diesel tank? Then set this page aside for now, keep the ignition and motor off, and phone 0333 366 0103. Caught before your motor runs, it is normally a drain and a thorough flush, done where the car is around Watchet. Here in advance? Then the rest explains why it comes about and what to stop it ever happening. ## Why does AdBlue in a diesel vehicle need its own filler? No single fluid but two: that is how plenty of newer diesels around Watchet and Williton carry, with diesel for the motor. AdBlue's own tank keeps it, and from there it goes to the exhaust, and there a spray cleans the fumes. Each tank comes with a filler of its own. Under one flap, next to each other: that is the arrangement on a lot of cars. Elsewhere, AdBlue's filler is under the bonnet or in your boot instead. The diesel side is filled at the petrol pump all the time. The AdBlue side is topped up far less regularly, usually from a bottle, and usually by someone who has to stop and think where it goes. Mistakes happen in that gap between them. ## How does AdBlue in your diesel tank take place around Watchet? Three things tend to come together, and carelessness is seldom one of them. The warning comes first. As AdBlue runs low the vehicle tells you, and if it runs out completely, the car drops into limp mode. So the top-up is done in a hurry: on a driveway off Market Street before work, or in the car park outside West Somerset Hotel on the way home. Unfamiliar vehicles come second, too. Hire cars, new motors and company vehicles put their fillers in new places, and habit reaches for the cap used on the old one. Third, the spout goes in: diesel filler or AdBlue one, it goes in as easily, and once the pour begins, no part stops it. The same few seconds decide it, in the middle of Watchet or out in St Decumans. ## Telling the AdBlue filler from the diesel filler A couple of seconds is all these take — so check them before you tip anything, on a drive in Washford or a forecourt in Watchet. - Blue and marking: an AdBlue cap is frequently blue, or says "AdBlue", where a diesel cap normally doesn't. Trust the cap, not its position. - Plenty of motors give AdBlue the smaller neck of the two. - A label inside your fuel flap often says which fuel goes where, on many motors. Check for it. - The handbook. If the filler is not by your diesel cap, it is in the boot or under the bonnet, and the handbook says which. - Whoever had it before will know. Ask as you collect a rental or company car — from the nearest station's car park, perhaps — not once the warning appears. ## Keeping AdBlue out of your diesel tank when you top up For the day the warning appears — anywhere it is in Somerset — a simple routine to use. - Not in a rush on the side of Mill Lane, not on a slope, not with your motor running: park and switch off first. - Say "AdBlue" out loud as you unscrew the cap, once you find the AdBlue filler and reading it. Daft, yes, but it works. - If both sit under one flap, check the diesel cap is still closed before you lift the bottle — then leave it on. - Gently does it, through the bottle's own spout, till it is full or the bottle runs out. - Before starting the car, close the cap and check a second time that the diesel cap never opened off. Spot at stage two or three that it's already gone into the diesel side? So stop just there. Don't carry on to step five. ## Watchet: already put AdBlue in your diesel tank? The short order of things, beginning with not starting your motor. The fuel pump starts on many diesels as soon as the ignition is switched on — so keep it off. Do not top up with diesel to dilute it: AdBlue doesn't mix with diesel, it sinks to the bottom of that tank, where your fuel is sucked from. The staff at Esso, Q8 or any forecourt will normally lend a hand to push your car away if you ask. Leave it where it is if you're on your own driveway around Watchet. Stop as soon as it is safe and switch off, if the engine has already run. On the M5, under 25 miles from Watchet, that means the next exit. Tell us about how far it went: a run towards Cardiff, under 25 miles away, is a bigger job than a short hop across Watchet. ## Watchet: what happens when our technicians get there Outside Knights Templar Community Church School & Nursery, near The Ancient Mariner or on your own drive: wherever the vehicle has stopped, we come to it. Which liquid went in, the quantity, and if it ran: our engineers ask since the answers decide the work and quote. You get that price on the phone, before anyone heads out. The fuel system is then purged thoroughly, once the tank is cleared. More than with petrol, it matters here: the crystals form, certain metals corrode, and none of it clears out on its own, however long it is left. Once the fuel filter is flushed — or replaced, where needed — fresh diesel is added, and then your vehicle is tested. Before leaving, our technicians start the engine and check that it's running correctly. Unrun cars mostly need a half-hour job after arrival. The kit is safe on a busy filling station, and quiet enough for a driveway after dark. Payment is on the day, not upfront, and you receive the paperwork your insurer wants: an engineer report and a VAT invoice. Before we get there, have a look at your insurance documents; many include cover for misfuelling. ## About Watchet itself Watchet is a small coastal town in Somerset, situated on the Bristol Channel at an elevation of around 12 metres. Watchet lies near the Quantock Hills, an Area of Outstanding Natural Beauty, and is close to several nearby villages, including St Decumans and Doniford. Watchet has a mix of housing types, with semi-detached homes being particularly prevalent, and is located approximately 21 miles from Cardiff. Watchet is also around 140 miles west of London, making it a relatively remote town in the South West region. ## AdBlue drains about Watchet, and Somerset beyond Throughout TA postcodes, our vans covering Watchet — a coastal town — work the nearby spots too, Doniford and Five Bells among them. Quickest of all: give a TA23 0 postcode to our van. No need to move the car. Our technicians drain it where it is — a side street close to Watchet Museum, a lay-by on the way to Watchet Memorial Ground, a drive. Assuming won't help at the back of Holy Cross Chapel, on a border, or anywhere hard to describe; phone and ask. ## For Watchet drivers, the short version Always, the cap; then, the tip. Even so AdBlue in your diesel tank? Petrol in Diesel will empty it where it stands, anywhere around Somerset: keep the car off and ring 0333 366 0103.