DEFENDER2.NET - View topic - How does DEF fluid work?

↓ Advertise on Defender2 ↓

Home · FAQ · New Posts · My Posts · PMs · Search · Members · Map · Calendar · Profile · Donate · Register · Log In

Home > General & Technical (L663) > How does DEF fluid work?

Page 1 of 2

Print this entire topic ·

Tim in Scotland

Member Since: 23 May 2007
Location: The Land that time forgot
Posts: 3750

How does DEF fluid work?

My new Defender is the first vehicle I have owned that uses DEF aka AdBlu fluid. All I have read on numerous LR forums is how much of the stuff LR vehicles seem to drink/pour down their throats.
So today 2.5months and 2000 miles after the last level check I decided to check the level as I was concerned that I might have to invest some of my pension in a couple of hundred quids worth of the stuff and to my surprise the car has hardly used any in 2000 miles of motoring. In June the range to empty on the dash was showing a tad over 6100 miles range, this morning 5975 miles range. 95% of my driving is offroad/fast A road/motorway Driving with 5% in the local town with two sets of traffic lights and a large roundabout to stop me. Am I in that oft quoted phrase from LR, ‘driving the car properly “ or have LR designed the exhaust system properly now that the DPF is “close coupled”
Two things I have noticed with this car I haven’t noticed on previous Diesel engine LR’s is very occassionally a strong smell outside the car and also that after turning off the engine there is a fan or pump that continues to run on for about 15 minutes after the engine is stopped - I assume that was the turbos cooling off but it could be the DPF system cooling too.

Any motor engineers here who can shed some light on the DEF consumption/ lack of and the fan/pump running? Pangea Green D250 90 HSE with Air Suspension, Off-road Pack, Towing Pack, Black Contrast roof , rear recovery eyes, Front bash plate, Classic flaps all round, extended wheel arch kit and a few bits from PowerfulUK Expel Clear Gloss PPF to come
2020 D240 1st Edition in Pangea Green with Acorn interior. Now gone - old faithful, no mechanical issues whatsoever ever but the leaks and rattles all over the place won’t be missed!

19th Aug 2020 10:31am

blackwolf

Member Since: 03 Nov 2009
Location: South West England
Posts: 16879

2007 Defender 110 Puma 2.4 DCPU Stornoway Grey

Wikipedia explains the chemistry and consumption better than I can: https://en.wikipedia.org/wiki/Diesel_exhaust_fluid and https://en.wikipedia.org/wiki/Selective_catalytic_reduction

The characteristics you describe such as the smell and the running fan seem to be general characterstics of modern diesels with SCRs, SWMBO's Skoda Yeti having exactly the same characteristics. I had always assumed but without giving the matter much thought that the fan was connected with DPF regeneration, since there is usually a smell of great (but not alarming) heat at the same time, but her L200, which is actually a year younger than the Yeti, doesn't do this and also doesn't have a DEF tank.

Thinking now, both vehicles have DPFs but I suspect that only the Yeti has an SCR cat as opposed to a 'normal' cat. I now wonder if it is the Selective Catalytic Reduction process rather than the DPF that is doing this.

Hopefully someone who really knows what they're talking about will provide an explanation!

19th Aug 2020 10:58am

jst

Member Since: 14 Jan 2008
Location: Taunton
Posts: 7687

2011 Defender 110 Puma 2.4 USW Stornoway Grey

if its anything like the audi miles to left for the adblue it will show very little change over 8 or 9 mths and then plummet in a matter of days! or could just be my wifes drivnig! Cheers

James
110 XS Utility
130 Puma Station wagon/camper (in the making)
90 Puma Hardtop

19th Aug 2020 12:31pm

lohr500

Member Since: 14 Sep 2014
Location: Skipton
Posts: 1285

2013 Defender 110 Puma 2.2 XS CSW Santorini Black

Interesting comment jst.
My Skoda Superb did the same thing and so does my Wrangler. Both with no obvious changes in driving style to cause an increase in consumption.
I just keep a 10l drum of it in the garage so I know I have enough on hand when needed.
The Wrangler needs 10 litres around every 3000 miles or so. The last lot I bought was £16 for 2 x 10 litres, so not an expensive carry on.

19th Aug 2020 2:02pm

milesr3

Member Since: 12 Feb 2013
Location: Suffolk
Posts: 873

2016 Defender 90 Puma 2.2 XS CSW Keswick Green

blackwolf wrote:
Wikipedia explains the chemistry and consumption better than I can: https://en.wikipedia.org/wiki/Diesel_exhaust_fluid

Which says "The injection rate of DEF into the exhaust depends on the specific after-treatment system, but is typically 2–6% of diesel consumption volume. This low dosing rate ensures long fluid refill intervals and minimizes the tank's size (and intrusion into vehicle packaging space)".

FWIW my Mercedes seems to be nearer to 1.5% of diesel consumption volume, based on a fag-packet calculation of not needing to refill the 22l AdBlue tank in-between 15,500 mile service intervals.

Last edited by milesr3 on 19th Aug 2020 5:34pm. Edited 1 time in total

19th Aug 2020 2:33pm

Tim in Scotland

Member Since: 23 May 2007
Location: The Land that time forgot
Posts: 3750

I noticed in the most recent “I don’t like the new Defender” video That he said the car had done 5000 miles and he had several DEF fluid level warnings scrolling on the screen. That was what prompted me to check mine!

Click image to enlarge Pangea Green D250 90 HSE with Air Suspension, Off-road Pack, Towing Pack, Black Contrast roof , rear recovery eyes, Front bash plate, Classic flaps all round, extended wheel arch kit and a few bits from PowerfulUK Expel Clear Gloss PPF to come
2020 D240 1st Edition in Pangea Green with Acorn interior. Now gone - old faithful, no mechanical issues whatsoever ever but the leaks and rattles all over the place won’t be missed!

19th Aug 2020 2:42pm

Roger

Member Since: 26 Apr 2018
Location: Hampshire
Posts: 71

2007 Defender 110 Puma 2.4 SW Java Black

Tim, when you do need to top up the AdBlu then toolstatio/screwfix are actually really competitively priced due to supplying various trades with copious quantities for their work vans, much cheaper than the local forecourt

19th Aug 2020 3:01pm

Tim in Scotland

Member Since: 23 May 2007
Location: The Land that time forgot
Posts: 3750

Cheers for the tip Roger. Pangea Green D250 90 HSE with Air Suspension, Off-road Pack, Towing Pack, Black Contrast roof , rear recovery eyes, Front bash plate, Classic flaps all round, extended wheel arch kit and a few bits from PowerfulUK Expel Clear Gloss PPF to come
2020 D240 1st Edition in Pangea Green with Acorn interior. Now gone - old faithful, no mechanical issues whatsoever ever but the leaks and rattles all over the place won’t be missed!

19th Aug 2020 3:25pm

J77

Member Since: 04 Nov 2019
Location: Fife
Posts: 3247

My Velar gets about 6000 miles on a tank, my D4 used to get 11000 miles on a tank, but temperatures and driving styles all have an impact. I filled up with Aldi AdBlue, it was £4.99 for 6 litres, ran sweet as a nut, according to my dealer Halfords AdBlue has caused issues in the past.

You will get plenty warning when it’s running low, if it runs out it won’t start.

19th Aug 2020 3:41pm

blackwolf

Member Since: 03 Nov 2009
Location: South West England
Posts: 16879

Tim in Scotland wrote:
I noticed in the most recent “I don’t like the new Defender” video That he said the car had done 5000 miles and he had several DEF fluid level warnings scrolling on the screen. That was what prompted me to check mine!

I wonder if it was full to start with.

19th Aug 2020 5:13pm

J77

Member Since: 04 Nov 2019
Location: Fife
Posts: 3247

Every chance, it seems to be over looked by a lot of dealers.

19th Aug 2020 5:21pm

RDR

Member Since: 27 Apr 2018
Location: Derbyshire
Posts: 570

My D4 used to get about 10k miles, the current D5 started complaining it was thirsty after 6K but I have a sneaking suspicion it wasn't full on delivery. 110 MY23.5 X Dynamic HSE
RR MY23 HSE PHEV
D5 MY19 HSE - Now Sold
D4 MY16 HSE Luxury - Now Sold
D4 MY12 HSE - Gone
D3 MY06 S - Gone but not forgotten

19th Aug 2020 6:19pm

lohr500

Member Since: 14 Sep 2014
Location: Skipton
Posts: 1285

J77 wrote:
My Velar gets about 6000 miles on a tank, my D4 used to get 11000 miles on a tank, but temperatures and driving styles all have an impact. I filled up with Aldi AdBlue, it was £4.99 for 6 litres, ran sweet as a nut, according to my dealer Halfords AdBlue has caused issues in the past.

You will get plenty warning when it’s running low, if it runs out it won’t start.

I wonder what the dealer charges for the privilege of procuring 10l of Adblue from them vs Halfords?

It's all supposed to be to ISO 22241 standard anyway. Another example of Main Stealer fake news, or fact?

19th Aug 2020 7:13pm

Pacha

Member Since: 23 Feb 2020
Location: North Yorkshire
Posts: 772

2008 Defender 90 Puma 2.4 HT Stornoway Grey

£9.99 for 10 litres @ Toolstation (Redex brand).

Don't want to be paying too much for urea..................

Rgds.

Chris

19th Aug 2020 7:15pm

J77

Member Since: 04 Nov 2019
Location: Fife
Posts: 3247

lohr500 wrote:
J77 wrote:
My Velar gets about 6000 miles on a tank, my D4 used to get 11000 miles on a tank, but temperatures and driving styles all have an impact. I filled up with Aldi AdBlue, it was £4.99 for 6 litres, ran sweet as a nut, according to my dealer Halfords AdBlue has caused issues in the past.

You will get plenty warning when it’s running low, if it runs out it won’t start.

I wonder what the dealer charges for the privilege of procuring 10l of Adblue from them vs Halfords?
It's all supposed to be to ISO 22241 standard anyway. Another example of Main Stealer fake news, or fact?

£29.99 for the dealer to top up or no charge with the service plan. No idea what they charge just for a top up bottle.

I’ve no idea if it’s true, they just said two owners had DEF system issues and both had used Halfords AdBlue.

19th Aug 2020 7:44pm

Page 1 of 2

All times are GMT + 1 Hour

Jump to

< Previous Topic | Next Topic >

Posting Rules

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum