Freezing (Waxing) point of Modern Diesel

[Norbreck21a]

I know this is primarily a site for petrol models, but there are quite a few of us on here with Sootchuckers, so I was wondering with current temperatures getting down to -20°C (-26°C apparently in Scotland last night), what is the temperature the modern Diesel starts to Wax or freeze (I know that Petrol is much lower than diesel) ?

Just interested ?

Andrew

[S2 Ant]

I actually googled this yesterday as the trainline that runs by my way reported issues due to the diesel freezing in the pipelines of their diesel trains!

Cant remember the numbers tho.... Google it and it'll come up

[Richn83]

Taken from a thread on detailing world from last January!

The applicable specification is BS EN 590:2009
There are two tests relating to cold flow properties or ‘waxing’:

•   Cloud Point – the temperature at which wax crystals first form
•   Cold Filter Plug Point (CFPP) – the temperature at which a standard fuel filter begins to block
The CFPP is the relevant one to consider. Specific additives are used to modify crystal growth to reduce the CFPP temperature.
EN 590 has 5 Climate-related requirements for cold flow properties (A to F) plus an additional 5 classes of ‘Arctic’ or extreme climate (0 to 4).

•   Class A CFPP +5degC
•   Class B CFPP 0degC
•   Class C CFPP -5degC
•   Class D CFPP -10degC
•   Class F CFPP -15degC
Arctic grades:

•   Class 0 CFPP -20degC
•   Class 1 CFPP -26degC
•   Class 2 CFPP -32degC
•   Class 3 CFPP -38degC
•   Class 4 CFPP -44degC
UK Winter Grade is Class F CFPP -15degC

Scandinavia, parts of Germany, Alpine France, Switzerland etc use one the Arctic classes depending on climate in the region – hence Bulla2000’s comment about -26degC (Class 1) in his region of Germany.

If you want a discourse on effects of a dirty fuel filter, why you should not add extra CFPP depression additives or petrol or kerosine, why some vehicles have problems when others don’t at the same temperature then just ask.
I used to manage oil refineries.

http://www.detailingworld.co.uk/forum/showthread.php?t=149233&page=3

[Norbreck21a]

Wow. top answer Rich 

So, if the UK grade is "F" i.e down to -15°C, then last night when near me experienced lowest temperatures of nearly -18°C, should I be worried that the car won't start ?

TBH, the Sootchucker has struggled a little lately, yet just a few months ago it had a new top of the range Bosch Platinum battery (slighty better cold crank amps than the OE one that came off). It always starts, just sounds like it's not going to ! Cranks over really slowly for the first second then catches and fires and starts immediately. Though it might have something to do with the weather ?

Andrew

[Richn83]

Saw another thread on Money saving expert forum, where someones Citreon wouldnt start from what the garage told them was diesel waxing.  So think it could happen in the current weather if you have a garage or can shelter the car near the house to keep the temp up a little reckon you will be alright 

[QD MBE]

Taken from a thread on detailing world from last January!

The applicable specification is BS EN 590:2009
There are two tests relating to cold flow properties or ‘waxing’:

•   Cloud Point – the temperature at which wax crystals first form
•   Cold Filter Plug Point (CFPP) – the temperature at which a standard fuel filter begins to block
The CFPP is the relevant one to consider. Specific additives are used to modify crystal growth to reduce the CFPP temperature.
EN 590 has 5 Climate-related requirements for cold flow properties (A to F) plus an additional 5 classes of ‘Arctic’ or extreme climate (0 to 4).

•   Class A CFPP +5degC
•   Class B CFPP 0degC
•   Class C CFPP -5degC
•   Class D CFPP -10degC
•   Class F CFPP -15degC
Arctic grades:

•   Class 0 CFPP -20degC
•   Class 1 CFPP -26degC
•   Class 2 CFPP -32degC
•   Class 3 CFPP -38degC
•   Class 4 CFPP -44degC
UK Winter Grade is Class F CFPP -15degC

Scandinavia, parts of Germany, Alpine France, Switzerland etc use one the Arctic classes depending on climate in the region – hence Bulla2000’s comment about -26degC (Class 1) in his region of Germany.

If you want a discourse on effects of a dirty fuel filter, why you should not add extra CFPP depression additives or petrol or kerosine, why some vehicles have problems when others don’t at the same temperature then just ask.
I used to manage oil refineries.

http://www.detailingworld.co.uk/forum/showthread.php?t=149233&page=3

I remember asking my dad about Octane numbers and MON/RON numbers (he was an Industrial Chemist specialising in the Petro-Chemical industry working for Shell then Octel).

Boy did I miss the next hour!   

[Richn83]

You should get him on to do us a thread Stoke 

[jmspear]

If it helps, my tractor - yes I know this is a GTI forum - , started fine 2 days ago, but is in an enclosed barn, towed the kids around my fields on a rubber ring then sledge (far more fun than trudging up and down hills) left in the field overnight, was down to -18deg C and it wouldnt start in the morning, flattened one battery and when on the second, I pulled the injectors and pitiful amount of diesel coming out (when cranked), it had waxxed up, so ended up towing it back to the barn with another tractor (which started s it was inside).

So in these temps you really do need to keep a car undercover or use one of those handy engine bay heaters that you can heat your engine bay with before you come out to start the car, a lot of lorry drivers, especially in Northern Europe use these!

[bodger00]

What a coincidence that this is raised today on here.

Our oil burner reported -14 this morning. Undetered I set off on my journey. The car sounded really rough and then stalled doing about 30 mph. It would not restart and on investigation it appeared waxing had occurred around the filler neck. I let the day warm a little and the car then ran fine for the rest of the day.

I have been to halfords tonight and put in an STP additive designed to improve cetaine levels and crucially anti gelling. Hope that fixes the problem.

[Norbreck21a]

Our oil burner reported -14 this morning. Undetered I set off on my journey. The car sounded really rough and then stalled doing about 30 mph. It would not restart and on investigation it appeared waxing had occurred around the filler neck. I let the day warm a little and the car then ran fine for the rest of the day.

This is exactly what was worrying me and why I started the thread.

We've seen temperatures down as low as -17°C and the car has seemed very sluggish to turn over. Luckily, it's always started and so far (fingers crossed) hasn't missed a beat. My car is left out each night (the wifes Polo get's the garage), so does seem to get the full force of the winter conditions.

Maybe the only thing that's helping is that it's parked alongside the garage in quite a sheltered spot between the garage and the house ?

Andrew

[amr_rm]

Remember you also have the effect of "oil stick" in the engine

It is not only the fuel that is getting cold but every component in the engine,

When i worked in R+D for the construction machinery industry, we used to have to cold chamber test to -30 degrees C for engine starts

At that temp it would take 4 hours for the engine oil inside the block to start to increase in viscous and would "stick" the pistons to the bores

It was like turning over a siezed/siezing engine untill the friction heate dthe oil a little.

Also one to remember is if you get waxed fuel in the tank, it won't unfreeze if you put the additive in, the additive will only work on non waxed fuel to stop it waxing

[Truckie]

This forum is unreal! Bang up to date as alway!  Just back from spending the day draining a full tank of diesel and changing the filter on our van. Was cutting out and struggling to start since sunday/monday when we recorded minus 16-18. seems to have cleared the problem, no lights on dash and revs for fun now! This probably wont be the last time this winter though, i have nowhere to shelter the van and snow/ice builds up around the tank on vivaros easily! Thanks for the info guys!

[divweir]

off topic well kind of   when i was a young lad 30 odd year ago
my old man had to light a fire under  tank in his lorry to get the
diesel to melt so it would start
dont think you would do that now.  bloody health and safety

[dmac1969]

If theres any water in your fuel system (due to contaminated fuel , dirty fuel filter ect) you will find that this will freeze in the lines before the diesel waxes up - its maybe good practice if you run a DERV to change your fuel filter before the winter?

[mattyw]

If it helps, my tractor - yes I know this is a GTI forum - , started fine 2 days ago, but is in an enclosed barn, towed the kids around my fields on a rubber ring then sledge (far more fun than trudging up and down hills) left in the field overnight, was down to -18deg C and it wouldnt start in the morning, flattened one battery and when on the second, I pulled the injectors and pitiful amount of diesel coming out (when cranked), it had waxxed up, so ended up towing it back to the barn with another tractor (which started s it was inside).

So in these temps you really do need to keep a car undercover or use one of those handy engine bay heaters that you can heat your engine bay with before you come out to start the car, a lot of lorry drivers, especially in Northern Europe use these!

thats probably down to using red diesel as it doesnt have the addatives that white fuel has,all our track machines and dumpers at work have been freezing up,we've been trying to get some waxing agent but hasnt been needed for years