--- title: AdBlue in a Diesel Tank Crabtree? Read This canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/crabtree-devon/ location: Crabtree county: Devon latitude: 50.388830 longitude: -4.089960 service: AdBlue in a Diesel Tank updated: 2026-10-26 --- # Crabtree: How Does AdBlue End Up in a Diesel Tank, and How Do You Avoid It? Pause reading a minute when the diesel tank already holds AdBlue in it: ignition off, motor off, then phone 0333 366 0103. Caught before the motor runs, it is usually a drain and a thorough flush, done where your car is around Crabtree. The rest of this page explains why it happens and how to ensure it does not — handy if you're reading ahead of time. ## Two fillers, two tanks: AdBlue in a diesel car Many newer diesels on the roads around Crabtree and Laira carry two liquids, not one. Diesel goes to the engine. Kept in a tank of its own, AdBlue is fed into your exhaust gas and cleans it. Each tank has its own filler. Plenty of motors have a single flap for both, while others move the AdBlue filler to the boot or under the bonnet. Diesel gets filled at each forecourt call-out, again and again. Far less often, the AdBlue side gets filled — normally from a bottle, by someone working out where it goes. The error lives in that gap. ## Crabtree: how AdBlue in the diesel tank occurs It is rarely carelessness. Three things tend to line up. First, the warning. Low AdBlue brings a message from your car, and letting it run out leads to limp mode — hence a hurried top-up, perhaps before work off Willow Close, perhaps at Windmill Inn on the way home that evening. The old car's filler is where the hand reaches — but a hire car, a new car or a company car keeps the fillers somewhere else. That's the second thing: a strange car. And the bottle fits. A bottle with a spout goes into a diesel filler as easily as an AdBlue one, and so nothing stops the tip once it has started. Marsh Mills or the heart of Crabtree: it takes the same few seconds in both. ## Telling the AdBlue filler from the diesel filler A few seconds is all the checks take — so check them before you pour anything, on a driveway in Woodford or a forecourt in Crabtree. - Blue and marking: an AdBlue cap is regularly blue, or says "AdBlue", where a diesel cap usually doesn't. Trust the cap, not where it sits. - Check the size: the smaller neck is, on many motors, the AdBlue one. - Lift the filler flap and look for a label — plenty of vehicles show what belongs in which filler right there. - In your boot or under the bonnet: that is where your filler is if it is not by the diesel cap, and the handbook says which. - Picking up a hire or company car, perhaps at the car park at Plymouth? Check with whoever drove the vehicle last before leaving, rather than when the light goes on. ## Topping up AdBlue without it reaching your diesel tank For the day the warning appears — wherever it is in Devon — a routine to follow. - Park and switch off. Not on a slope, not with your engine running, and not in a rush on the side of Appleton Tor Close. - 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 both sit under a flap, confirm it's closed before the bottle comes up. - Finish when the tank is topped up or the bottle is empty; before that, tip slowly through the own spout. - Before you start your car, shut the cap and check a second time that your diesel cap never came off. Find at stage two or three that it's already gone into the diesel side? So stop just there. Do not go on to step five. ## Crabtree: already put AdBlue in your diesel tank? Then the order of things is short. Don't start your engine. Leave the ignition off too, since on many diesels switching it on alone starts your pump. Thinning it with more diesel fails, since AdBlue settles to the bottom rather than mixing — and that's where the fuel is pulled from. If you're at a forecourt, whether it is the Sainsbury's or the Esso, ask the staff to help roll the car clear of the pump. If you are on your own drive around Crabtree, leave it where it stands. If your motor has already run, stop as soon as it is safe then switch off. On the M5, under 50 miles from Crabtree, that means the next junction. Tell us about how far it went: a run towards Plymouth, under 3 miles away, is a bigger job than a short hop across Crabtree. ## When we arrive in Crabtree, what happens? Wherever your car has stopped, be it outside Woodford Primary School, beside Efford Fort or on your own drive, the van travels to it. Our engineers ask what got in, roughly how much, and whether it's run, since those answers settle the work and our price. On the phone call itself, you hear our quote — ahead of anything else. The system is then purged thoroughly, once the tank is cleared. Not like petrol, AdBlue forms crystals and eats at certain fuel-system metals, and none of that clears away unaided. Hence it matters more. Filter cleaned or, if it must be, replaced; fresh diesel in; then a check of your car. Your engine is fired up next and checked to confirm it runs properly, all before we head off. Most jobs are finished in roughly half an hour once our technicians arrive, as long as your engine has not run — and the pumps our engineers use are safe on a live forecourt yet quiet at night outside a house. Your insurer will ask for an engineer's report and the VAT invoice, and both are yours at the end. Payment is on the day, with no deposit. Before we get there, have a look at your insurance documents; many include cover for misfuelling. ## About Crabtree itself Crabtree is a suburban area located near the coast in Devon, sitting approximately 10 metres above sea level. Crabtree is close to the city of Plymouth, with Marsh Mills, Longbridge, and Efford nearby. Crabtree has a population of around 1545 people and predominantly consists of semi-detached housing. Crabtree is situated near the southern coast of England, about 189 miles from London. ## AdBlue drains about Crabtree, and Devon beyond Crabtree is a residential suburb, and our teams that cover it also work the towns around it, Longbridge and Efford among them, across the PL postcode area. Fastest of all: give a PL3 6 postcode for the van. The vehicle remains where it is. The drain happens on the spot, be it a drive, a road near St Boniface Arena, or a layby on the way to Efford Marsh Nature Reserve. Assuming doesn't help behind Plymouth Coliseum, on a border, or somewhere hard to pin down; phone and check. ## For Crabtree people, the short version Before you tip, read the cap. Even so AdBlue in your diesel tank? Petrol in Diesel can drain it where it stands, wherever across Devon: keep the car off then phone 0333 366 0103.