How It Happens and How to Avoid It: AdBlue in a Diesel Tank in Derry Downs
If AdBlue is already in your diesel tank, stop reading for a moment: leave your motor and your ignition off and phone 0333 366 0103. Around Derry Downs, finding it before your motor runs normally means a drain and a full flush where it stands. The rest of this page covers why it occurs and how to make sure it does not — useful if you are reading ahead of time.
Two fillers, two tanks: AdBlue in a diesel motor
Many newer diesels around Goddington, like those in Derry Downs, carry on two fluids; the motor gets just the diesel. AdBlue's own tank keeps it, and from there it goes to the exhaust, and there a spray treats the fumes.
Each tank has its own filler. Other motors put the AdBlue filler in the boot or under the bonnet; a lot of others have the two together behind one flap. Diesel goes in at each filling station visit, week in, week out. Much less regularly, the AdBlue side gets filled — mostly from a bottle, by a person thinking about where it goes. The error lives in that gap.
How does AdBlue in your diesel tank happen around Derry Downs?
It is rarely carelessness. Three things tend to line up.
On a driveway off Chelsfield Lane before work, or in the car park outside Beech Tree heading home: that is where the rushed top-up happens. Why the rush? As AdBlue gets low the car warns you, and once it's gone, limp mode kicks in.
Then, the hand goes for the cap it knew on the old car — because a hire car, a new vehicle or a company car places the fillers where your last one didn't.
No part stops the tip after it has started, since a bottle with a spout goes into a diesel filler as readily as an AdBlue one. The bottle fits. The same few seconds settle it, in the middle of Derry Downs or out in St Mary Cray.
The AdBlue filler and your diesel filler: telling them apart
A couple of seconds is all the checks take — so check them before you tip anything, on a drive in Poverest or a forecourt in Derry Downs.
- Position misleads; the cap doesn't. AdBlue ones tend to be blue or bear the name "AdBlue" — diesel ones normally don't.
- Look at the size: the smaller neck is, on many vehicles, the AdBlue one.
- A label inside your fuel flap often shows which fuel goes where, on plenty of vehicles. Check for it.
- The handbook. If the filler is not by your diesel cap, it's in your boot or under the bonnet, and the handbook says which.
- Picking up a hire or company car, say at the car park at St Mary Cray? Ask the person who drove the car last before you set off, rather than once the light goes on.
Keeping AdBlue out of your diesel tank when you top up
Anywhere across Greater London the light comes on, here is a routine for the day.
- Turn off once parked — level ground, motor off, and not in a rush by Beamish Road at the roadside.
- Locate the AdBlue filler, check the cap, and say the word "AdBlue" aloud as unscrewing it. It sounds daft. It works.
- The two behind one flap? So make sure the lid on your diesel filler stays shut before lifting the bottle.
- Using the bottle's own spout, pour slowly — and stop when it is full or the bottle is empty.
- Close the cap and check again. Make sure the diesel cap was never opened. Only then start the car.
Find at the second or third stage that the bottle went in the diesel tank? That's where you stop. Don't carry on to step five.
AdBlue in your diesel tank already, in Derry Downs?
Then the order of things is short. Don't start the engine. The fuel pump runs on many diesels the moment the ignition is switched on — so keep it off. Don't top up with diesel to dilute it: AdBlue does not mix with diesel, it sinks to the bottom of the tank, where the fuel is pulled from.
The staff at Texaco, BP or any forecourt will normally lend a hand pushing the vehicle away when you ask. Leave it where it is if you're on your own drive around Derry Downs.
Where the motor has run already, pull over safely and switch the car off. On the M25, under 3 miles from Derry Downs, that means the next exit. Tell us roughly how far it went: a run towards London, under 15 miles away, is a bigger job than a short hop across Derry Downs.
Our arrival in Derry Downs, and what occurs next
We come to your car wherever it has stopped, whether that's outside St Philomena's Primary School, near The Salvation Army or on your own driveway. Those replies determine the work and the price, and so our technicians ask what went in, roughly how much, and if it's run. During the phone call itself, you are told our price — ahead of anything else.
Emptying your tank comes next, then a full flush of your system. AdBlue crystallises and is corrosive to some of the metals in a fuel system, and so it doesn't wash out on its own — which is why that matters more with AdBlue than with petrol. Once the fuel filter is flushed — or renewed, if required — fresh diesel goes in, and then the car gets tested. We do not leave until it has been fired up and is running properly.
Most jobs are done in roughly half an hour after we get there, as long as the engine hasn't run — and the pumps our engineers use are safe on a busy forecourt and quiet at night outside a house. Nothing in advance; you settle up on the day. Afterwards, a VAT invoice and a report from the engineer are handed to you for the insurer. It's worth looking at your policy as the van travels to you: misfuelling cover is included with plenty of policies.
About Derry Downs itself
Derry Downs is a suburban area in south-east London, situated approximately 13 miles from central London. Derry Downs has a relatively low elevation of around 65 metres and is characterised by semi-detached housing. Derry Downs is located near other suburban areas such as St Mary Cray, Kevingtown, and Ramsden, and is home to a population of around 6128 residents.
AdBlue drains across Greater London, Derry Downs included
Over BR postcodes, the vans that cover Derry Downs — a residential suburb — work the surrounding places too, Ramsden and Kevingtown among them. Fastest of all: give a BR5 4 postcode to the van.
The car does not need to move. The drain happens on the spot, be it a driveway, a road by Unity Church, or a layby on the way to Grassmeade Recreation Ground. Tricky to pin down, like the back of Bromley Indoor Bowls Centre? Close to a county line? Checking is better than guessing, so ring.
In short, for Derry Downs motorists
Pour nothing till you have read the cap. If AdBlue has gone in your diesel tank all the same, leave the vehicle off then ring 0333 366 0103. Petrol in Diesel empties it where it waits, anywhere around Greater London.