Ad Blue - remove or treat ?

[Hawthorn37]

I’ve read the many posts on here about the costly effects of Ad Blue crystallisation, and want to avoid it.

We’re doing fewer miles in our Cali this year, and I’m aware the last time I filled the Ad Blue tank was over 12 months ago. After the refill it gave 18,500 miles range. Currently the van has 15,000 miles Ad Blue range (which sounds about right).

My questions are:
1. At what point does Ad Blue become an issue re crystallisation? What is “too old” ?
2. Is adding a bottle of additive sufficient to keep it healthy?
3. Should I siphon out the old Ad Blue and replace with (a smaller volume ) of new Ad Blue? Is this okay to do - or will it it mess up the engine management or something?

Many thanks.

 

[Perfectos]

#1 see photo attached
#2 Probably not - see #1
#3 The van should see the volume has changed, the tank level sensor should "check" the ad blue level upon turning the ignition on.

Is it best to have a full tank of ad blue or partial tank with air gap ?
TBH I think the ad blue issues are a bit of a lottery, given the number of vehicles on the road, all manufacturers have issues with the systems and there is a whole industry sprung up to fix the issues caused by ad blue in vehicles. Im not sure there is a definitive answer to the issue.


Additional info

AdBlue Tank Flush: When to Drain & Refill | Step-by-Step

When an AdBlue tank flush is needed rather than a top-up, the full drain and refill procedure step by step, and what to check if the warning returns.

adbluespecialist.co.uk

Expert Guide- Small AdBlue Diesel Drain Procedure

24/7 Nationwide AdBlue in Diesel Tank Rescue: 07459 909935National AdBlue Drain Rescue: https://www.adblue-in-diesel-tank-specialist.co.uk/If you found this page, we cover you!Nothing derails a schedule faster than unexpected operational downtime, especially when it involves modern selective...

www.adblue-in-diesel-tank-specialist.co.uk

 

[Hawthorn37]

#1 see photo attached
#2 Probably not - see #1
#3 The van should see the volume has changed, the tank level sensor should "check" the ad blue level upon turning the ignition on.

Is it best to have a full tank of ad blue or partial tank with air gap ?
TBH I think the ad blue issues are a bit of a lottery, given the number of vehicles on the road, all manufacturers have issues with the systems and there is a whole industry sprung up to fix the issues caused by ad blue in vehicles. Im not sure there is a definitive answer to the issue.

View attachment 152391
Additional info

AdBlue Tank Flush: When to Drain & Refill | Step-by-Step

When an AdBlue tank flush is needed rather than a top-up, the full drain and refill procedure step by step, and what to check if the warning returns.

adbluespecialist.co.uk

Expert Guide- Small AdBlue Diesel Drain Procedure

24/7 Nationwide AdBlue in Diesel Tank Rescue: 07459 909935National AdBlue Drain Rescue: https://www.adblue-in-diesel-tank-specialist.co.uk/If you found this page, we cover you!Nothing derails a schedule faster than unexpected operational downtime, especially when it involves modern selective...

www.adblue-in-diesel-tank-specialist.co.uk

“Is it best to have a full tank of ad blue or partial tank with air gap ?”

That’s what considering. I’ve read about overfilling issues, but if the tank has a low level, would that promote crystal growth on the walls ??

 

[dspuk]

“Is it best to have a full tank of ad blue or partial tank with air gap ?”

That’s what considering. I’ve read about overfilling issues, but if the tank has a low level, would that promote crystal growth on the walls ??

From what I read the biggest issue is cold.

Keeping it as full as possible will mean the cold should affect it less.

 

[Perfectos]

My research: Heat is a real problem for storage, above 20 degrees C it goes off and crystallises rapidly.

The system has heaters to deal with cold conditions. Repeated freezing appears to cause crystals

It's a Goldie locks system !

 

[temporarysecretary]

So definitely don't buy it from those petrol forecourts where its sat outside.

The temperature window is interesting. My Vauxhall work van says in the owners manual not to fill up the ad blue when its below 11 degrees C. In the winter we drive round with it in the footwell to warm it up first as they are also plagued with adblue issues.

 

[Hawthorn37]

So maybe the best plan is to siphon most of it out; buy new Ad Blue from somewhere with fast moving stock (say Halfords or Costco) - but still checking the manufacturing date; condition the container to around 15-18 degC; refill when the ambient temperature is okay; get the tank to almost full but don’t overfill.

Half my brain thinks this would be wise, the other half “if it ain’t broke, don’t fix it”

 

[lohr500]

I'm in a similar situation in that we haven't put may miles on our Cali this year and most of the journeys have been short.

I am reluctant to start syphoning out and refilling the Adblue in case that causes the sensor to have a hissy fit when switching the ignition back on. Although I guess if one added exactly the same amount as syphoned out, would the vehicle kno any difference?

Has anyone tried syphoning out the AdBlue? Is it possible to get a thin syphon pipe far enough into the tank?

For better or worse, I have gone down the Wynn's additive route in the hope that this will keep any crystallisation issues at bay.

 

[chockswahay]

So maybe the best plan is to siphon most of it out; buy new Ad Blue from somewhere with fast moving stock (say Halfords or Costco) - but still checking the manufacturing date; condition the container to around 15-18 degC; refill when the ambient temperature is okay; get the tank to almost full but don’t overfill.

Half my brain thinks this would be wise, the other half “if it ain’t broke, don’t fix it”

If you do it old skool like we did with petrol when we were teenagers the biggest problem is likely to be a mouthful of pig p!$$

 

[Perfectos]

If you do it old skool like we did with petrol when we were teenagers the biggest problem is likely to be a mouthful of pig p!$$

You could / can use a large syringe!

Thin tube will go into the tank, will need to get the tube in between baffles and then sit below the fluid level.

The syringe will be needed to extract all the liquid, siphon will help to a point

 

[acer]

Go for it old school style!
Large syringe? Where’s the joy? Where’s the jeopardy?

 

[temporarysecretary]

Im not sure its worth the effort.

If you leave an old bottle of adblue sealed it doesn't crystalise.

If you splash some brand new adblue anywhere it will crystalise.

Id just fill up exactly what it asks for when it asks for it and hope for the best in between.

Especially when most issues seem to be fill sensor related.

 

[WelshGas]

Something else for those who leave their vehicles over winter to worry about.

Does diesel go off in the fuel tank?

DIesel fuel does go off, lasting about 6 to 12 months in a standard fuel tank before it begins to degrade. [1]

How Diesel Degrades

• • Oxidation: Contact with air breaks down the fuel's chemical structure, creating acids, gum, and dark, sticky sludge. [1, 2]
  • Water Contamination: Temperature changes cause condensation to form inside the tank. Water sinks to the bottom because it is heavier than diesel. [1, 2]
  • Microbial Growth: Water meets the diesel interface and breeds bacteria and fungi (often called the "diesel bug") that form thick microbial slime. [1, 2, 3]
  • Loss of Sulfur: Modern ultra-low sulfur diesel (ULSD) has fewer natural preservatives than older formulas, making it less stable

 

[chockswahay]

Im not sure its worth the effort.

If you leave an old bottle of adblue sealed it doesn't crystalise.

If you splash some brand new adblue anywhere it will crystalise.

Id just fill up exactly what it asks for when it asks for it and hope for the best in between.

Especially when most issues seem to be fill sensor related.

But, Mrs Acer has already said “if only I knew a man’ …………. Syphoning the stuff ‘old skool’ style is Acers chance to step up and prove himself! It’s a win/win!

 

[chockswahay]

Something else for those who leave their vehicles over winter to worry about.

Does diesel go off in the fuel tank?

DIesel fuel does go off, lasting about 6 to 12 months in a standard fuel tank before it begins to degrade. [1]

How Diesel Degrades

• • Oxidation: Contact with air breaks down the fuel's chemical structure, creating acids, gum, and dark, sticky sludge. [1, 2]
  • Water Contamination: Temperature changes cause condensation to form inside the tank. Water sinks to the bottom because it is heavier than diesel. [1, 2]
  • Microbial Growth: Water meets the diesel interface and breeds bacteria and fungi (often called the "diesel bug") that form thick microbial slime. [1, 2, 3]
  • Loss of Sulfur: Modern ultra-low sulfur diesel (ULSD) has fewer natural preservatives than older formulas, making it less stable

Takes me back to my boating days …….. we would fill the tank to the brim at the end of the season and add a suitable additive to prevent ‘diesel bug’. Surely such a thing exists for road vehicles?

 

[acer]

But, Mrs Acer has already said “if only I knew a man’ …………. Syphoning the stuff ‘old skool’ style is Acers chance to step up and prove himself! It’s a win/win!

I’m hard!
I drink pints of adblue, me

 

[WelshGas]

Takes me back to my boating days …….. we would fill the tank to the brim at the end of the season and add a suitable additive to prevent ‘diesel bug’. Surely such a thing exists for road vehicles?

I believe there might be.

 

[WelshGas]

I’m hard!
I drink pints of adblue, me

Isn't there a colloquial term for that, oh yes " wee wee Artist "?

 

[Black Forest]

Interesting on the Adblu / cold / crystals topic.
Our van stands outside all winter and sometimes its weeks below freezing

I just bought some Wynns additive and will dose 20cc / 10 litres. Buying fresh from a pump seems a better option than the containers that could be standing for ages....

 

[acer]

Isn't there a colloquial term for that, oh yes " wee wee Artist "?

You should see the crystals that I can produce after a few pints

 

[Perfectos]

You should see the crystals that I can produce after a few pints

Crystal meth ?

 

[chockswahay]

Isn't there a colloquial term for that, oh yes " wee wee Artist "?

So……. an Adblue Artist then

 

[Hawthorn37]

Something else for those who leave their vehicles over winter to worry about.

Does diesel go off in the fuel tank?

DIesel fuel does go off, lasting about 6 to 12 months in a standard fuel tank before it begins to degrade. [1]

How Diesel Degrades

• • Oxidation: Contact with air breaks down the fuel's chemical structure, creating acids, gum, and dark, sticky sludge. [1, 2]
  • Water Contamination: Temperature changes cause condensation to form inside the tank. Water sinks to the bottom because it is heavier than diesel. [1, 2]
  • Microbial Growth: Water meets the diesel interface and breeds bacteria and fungi (often called the "diesel bug") that form thick microbial slime. [1, 2, 3]
  • Loss of Sulfur: Modern ultra-low sulfur diesel (ULSD) has fewer natural preservatives than older formulas, making it less stable

I’m waiting for the Orange One to make me a good offer for my strategic diesel reserves.

 

[Hawthorn37]

I’ve come to the conclusion that I’ll be adding the Wynns anti crystallisation additive, and otherwise leaving well alone. As @lohr500 suggests, it wouldn’t be great if I was to create a fault by siphoning and refilling.

So thanks for all your suggestions and comments.

 

[lohr500]

Cheapest Wynn's I found was a twin pack on ebay for £12.95 including the postage.

I used one and now have the second to hand ready for the next Adblue fill.