Winter Diesel: Flow Improver for Summer Fuel

Hello everyone,
I still have a few liters of summer diesel left over from my old company.
Since I can't use all of this product before the temperature drops to freezing, I was thinking about using this "Diesel Anti-Gel" instead.

http://www.bardahlgermany.com/p/479222601/bardahl-diesel-anti-gel-fliessverbesserer-1-liter?psm=d0SHloLhp2xxf8K%2B4lxMJ3UH5VN0bFbbI1yhxD6dy%2Fc%3D&cid=google_base


What would you advise me to do?
Would that work, or should I use winter diesel from the gas station instead during the winter?

Thank you very much.

Okay, I would mix it with winter diesel depending on the temperature, instead of using additives.

I've been thinking about that as well, even down to temperatures of -10°C.
But what if it clumps up inside the containers?

I had the same problem this year.
There are several canisters of summer diesel fuel left on the boat, and winter is just around the corner.

Adding winter diesel doesn't really help much because crystals start to form at temperatures around 0-5 degrees Celsius, and they don't dissolve again even below 5-10 degrees Celsius, no matter how much additive or winter diesel you add.
On the other hand, it might work because diesel and gasoline engines tend to heat up their fuel tanks quite a bit on longer journeys.

Solution 1: Use a winter additive like "Winter-Fliess-Fit" from Liq.moly (approximately 10 euros for 1 liter, enough for about 1000 liters of water; it was suddenly sold out last winter). Just pour it into the measuring cap and it works.
It's important to add it before the formation of crystals begins, so above 5-8 degrees Celsius. However, it may also re-separate if left standing for a long time.

Anyway, last winter I deliberately made sure to park my TDI in a place where it would be exposed to the -22 degrees Celsius temperatures, and it worked perfectly fine. Unlike my neighbor's diesel car...

Solution 2: When it's cold (was), refuel using a funnel and leave about the bottom 10-20% of the sediment in the tank. The paraffin precipitates seem to settle at the bottom and make the yellow diesel appear very milky. PoorMan's - DIY winter diesel.

Hi,

Flow improvers are not suitable for summer diesel in the winter. You need a WASA (wax anti-settling additive). This doesn't prevent paraffin from precipitating out, but it does prevent the precipitated paraffins from clumping together into larger clumps.
The interaction between the WASA you are adding and the additives already present in your diesel fuel from the refinery is problematic. You will not be able to rule out the possibility that undesirable interactions are occurring here.
Unfortunately, you don't have a way to determine the Cetane Number (CFPP) of the diesel fuel, because the cloudiness itself is not necessarily an indication that the diesel fuel is no longer working properly in your engine. I would either:
1.) Leave the diesel in the boat's fuel tank – you'll be back on the water next spring, and with temperatures just above freezing, the diesel will flow through the boat's engine filter again.
2.) If diesel fuel absolutely must be used in the car: Make sure it is only stored overnight in the vehicle's tank if there is only a slight frost.

If the storage location is moderately warm at night (an unheated garage or your own garage usually suffices) and the daytime temperatures are within a safe range, you can gradually add fuel to the vehicle in the evening according to your daily usage and slowly burn it off. This works really well if you commute for work and drive the same routes every day with little variation. In that case, you can estimate the daily fuel needs quite accurately and refuel accordingly.

Will winter diesel gradually start appearing at gas stations towards the end of September or early October?
If I mix the summer diesel and winter additives in a 1:1 ratio before anything else happens, will the summer diesel still crystallize at low minus temperatures?

Adding the anti-freeze additive costs money, so gas stations only deliver diesel fuel with the appropriate level of freeze resistance when it is absolutely necessary. For the average consumer, especially those who primarily park their cars under streetlights, the timing is a matter of chance.

In Germany, diesel fuel must comply with the DIN EN 590 standard. This means that the Cloud Point Filterability Test (CFPT) – measured as the lowest temperature at which the fuel will filter through a standard test filter – must be between -10°C for grades 1.10 to 1.15 and 1.3, and 1.4. From November 16th to February 28th, a CFPT of at least -20°C is required.
The cold-weather performance of diesel fuel is achieved through its composition (e.g., the kerosene content) and by adding additives.
The effectiveness of flow improvers depends on the composition of the existing diesel fuel. Diesel that is already saturated with additives cannot be further improved by adding more additives; in fact, the additives in the mixture may have the opposite effect.
I would have been less critical of adding flow improver to pure summer diesel, but I wouldn't necessarily expect it to immediately result in a winter-grade diesel fuel that is suitable for temperatures down to -20°C.
hg
Herbert.

I would be satisfied if it could maintain a temperature of at least -10°C.
Then I could also overwinter it in the unheated communal garage.

I'll give it a try, and when it gets colder, I'll switch to fuel from the pump.

The referenced DIN EN 590 standard defines the properties that diesel fuel should have during its production. However, what is actually delivered to end consumers often deviates significantly from this, especially during transition periods. Assuming that manufacturers are supplying fuel produced in accordance with seasonal regulations, the subsequent distribution chain plays a crucial role in how quickly this fuel reaches consumers' tanks. Large petroleum retailers with relatively small storage capacities (keyword: "just in time") typically replenish their tanks and delivery vehicles fairly quickly. The larger the storage capacity, the more pronounced the initial dilution of the winter additives, and there may also be stronger interactions with other components. Things become particularly interesting when smaller petroleum retailers regularly source their fuel from different suppliers. While large companies in the industry benefit from price discounts for long-term contracts and corresponding purchase volumes, smaller companies have the flexibility and independence to shop where they currently get the best prices, based on actual sales.

Here's a translation of the German text into English:

"As an example, I have a self-service gas station in my town that is operated by a transportation company. The prices are always lower than those at competing stations with attendants, sometimes just one cent less, and sometimes 15 cents. They only offer diesel fuel, and the tank capacity has been expanded to 45,000 liters. I've received truck diesel there in various colors: colorless, green, blue, or yellow. The fuel smells different each time when filling up, and some "types" have a very distinct aroma during combustion. Despite this, I've never had any problems with it, not even during the extremely cold temperatures of -20 degrees Celsius at the end of January this year. As long as the transportation company is fueling its own vehicles there, I don't worry about it. I also know that they are supplied once or twice a week, and that practically every delivery comes from somewhere else."

Hi,

If it's just about overwintering, you won't have any problems. You just shouldn't be alarmed if the summer diesel consists of white paraffin crystals at the bottom when the temperature is below freezing. When the temperatures rise again, the paraffin crystals will dissolve.

Regarding EN590:
Generally, as mentioned before, there are fixed periods for summer, transitional, and winter products. However, it still happens that vehicles won't start in extremely low temperatures because the diesel fuel, despite having a Cold Filter Plugging Point (CFPP) of -28°C, "refuses" to function even at -23°C. Wasn't this actually a problem in the greater Munich area last year?

Yes, we experienced a similar problem here in January. There were two consecutive nights with temperatures of -28 degrees Celsius, and as a result, about three-quarters of my colleagues' vehicles, whether diesel or gasoline powered, were unable to start. The diesels had fuel from the gas station, which was generally not old. However, the gasoline cars that had been filled with E10 also wouldn't start. Several colleagues' FSI engines, which were fueled with Super Plus, did run properly, and my boss's V6 Galant also started without any issues when using Super Plus.

Winter diesel fuel has a cloud point (CFP) of -20°C or lower, not -28°C. "Premium diesel" may have even lower values depending on the manufacturer and weather conditions.
Whether a standard deicing fluid can remain liquid at temperatures below -20°C depends on the composition of the deicing fluid and the anti-freezing agent used, as well as the temperature during mixing.
hg
Herbert.

How exactly do the paraffin crystals behave in this case?
Some people claim that at warmer temperatures, it completely dissolves again, while others argue that once it has formed proper crystals, it is no longer usable.

If the diesel fuel crystallizes, it will dissolve again if it gets warm enough. In some cases, pouring a bucket of hot water over the diesel filter helps; in more stubborn cases, leaving it overnight in a warm hall is necessary.
hg
Herbert.