How to prevent freezing of diesel fuel and how to defrost it
Content
Those who drive gasoline engines in cold temperate climates don't think about fuel temperature problems. But diesel is another matter. If you neglect the seasonal replacement of diesel fuel, then when cold weather sets in, you can quickly and permanently immobilize the car.
Diesel fuel at a negative temperature will stop pumping and tightly clog all channels of the fuel equipment.
Features of summer diesel fuel
Literally a few degrees below zero will turn summer diesel fuel into a viscous substance, from which paraffins will begin to fall out.
Theoretically, if the fuel meets the standards, it should pass through the filter to -8 degrees. But in practice, it will be almost unusable and will begin to clog his pores already at -5. For summer trains, this is normal, but it is detrimental to the performance of the motor.
The filter will fail first. This is enough to stop the engine. But similar deposits will be throughout the line, in the tank, pipes, pumps and nozzles.
Even just warming up the system to revive the engine and replace diesel fuel will be very difficult. For cold, regardless of the climatic features of the region, winter diesel fuel should be used. The problem will arise without warning, so you need to take care of the motor in advance.
Freezing point
The exact composition of diesel fuel for various seasonal purposes is not standardized. They differ indirectly in density (viscosity) at a certain temperature. Winter varieties are about one and a half to two times less viscous.
Summer diesel
Summer fuel is better and cheaper than all others, but only if used in weather conditions with a positive temperature. It thickens to the filterability threshold at -5 degrees.
Even with the approach to this indicator, the fuel will already become cloudy and begin to form a precipitate. In modern power systems, when everything is designed for ideally clean fuel with strictly normalized physical parameters, even the slightest appearance of solid or gel-like insoluble impurities is unacceptable.
It's not even about freezing. If the engine stopped due to a violation of the composition of the mixture, then diesel fuel is definitely unsuitable, so it makes no sense to talk about complete transformation into a solid phase.
Moreover, the composition of the fuel by fractions is highly dependent on the feedstock and manufacturer's technologies, and the consequences are frightening, therefore, at near zero temperatures, this grade is categorically unacceptable to use. Even heating through the return lines will not save, the heat generation there is small, and the mass of diesel fuel in the tank is large.
Demi-season fuel
An intermediate variety, called off-season according to GOST, allows cooling at a filterability threshold of up to -15 degrees. At the same time, the useful characteristics of summer diesel fuel are preserved, in particular, the cetane number, which is important for softening the operating cycle of loaded turbocharged diesel engines with high filling rates and power density.
Commercial grade scores are usually met with some margin, but don't rely on that. Relatively speaking, this is fuel for the southern regions with their mild, but not always predictable winters.
For example, high temperatures can be observed there during the day, when it is desirable to feed the diesel with high-quality fuel, but there is a danger of clouding it with the formation of sediment and damage to filters during slight night frosts.
Winter diesel fuel
Winter varieties feel confident at low temperatures down to minus 25-30 degrees, but be sure to take into account the specific design of the product.
It is possible that one will thicken before the filter stops working at -25, while others will endure -35. Usually a specific threshold for use is indicated in the labeling of this type of fuel, it must be known to the driver from the certificate.
If it is planned to use a diesel car in very extreme frosty conditions, then it will be necessary to refuel exclusively with arctic diesel fuel. It is filtered depending on the brand up to -40 and even lower.
It may happen that local cooling will exceed all reasonable limits, but usually in automotive technology for such conditions special measures are taken to heat the tank and fuel system, and the engines are not turned off in winter.
How to choose and use diesel fuel all year round
You don’t have to worry about summer fuel, but in winter it is better to choose diesel fuel exclusively at gas stations of large brands. The experience of motorists shows that commercial winter diesel fuel from well-known companies meets the requirements of GOST with a large margin.
Up to -25 no problem with any product as long as it is stated to be for winter use. Below you should use exclusively arctic diesel fuel, it will not even become cloudy up to -35.
It is not worth buying fuel from small distributors in winter, since its properties can change unpredictably during storage and when mixed in tanks with the remains of summer fuel.
Is it possible to drive in winter on summer diesel fuel
In severe frosts, such experiments on your own expensive motor are unacceptable. But in the most extreme cases and a small negative temperature, you can add special compounds to the tank that reduce the temperature threshold.
Such antigels allow it to change by a few degrees, but no more. You must first study the specific characteristics and procedure for use according to the manufacturer. And remember that this is only a temporary measure.
It is now unacceptable to dilute fuel with kerosene, and even more so with gasoline, as old drivers did on outdated engines. On such mixtures, the motor will not live for a long time, its specific characteristics are too high, and everything works close to the tensile strength anyway.
Signs of freezing fuel in a car
The first and main sign of exceeding the limit of fuel resistance to frost will be the failure of the engine to start. It just won't get the right amount of diesel fuel to ignite and run smoothly.
If freezing began on the go, then the diesel engine will lose traction, start to triple and will not be able to spin up to the nominal speed.
Visually, clouding of the usually transparent diesel fuel will be noticeable, then precipitation and crystallization. The filter on which they tried to start the engine with such fuel will become unusable and must be replaced. Driving on unfiltered fuel is unacceptable.
How to defrost solar
It is useless to use anti-gels or other defrosting agents when a precipitate has already formed in the fuel, it is not filtered and the engine does not start. They simply will not get into places clogged with paraffins.
You can try to heat the bottleneck in the fuel system - the filter. The bottleneck is there in the first place. But all other areas, including the fuel tank, will also have to be heated. Therefore, the cardinal decision will be to install the machine in a heated room.
Much depends on the complexity and modernity of the car. Old trucks were warmed up not only with a hairdryer, but even with a blowtorch. Now this is unacceptable.
Of the folk methods, it is possible to note the creation of a kind of plastic film greenhouse over the car. Hot air is blown through it from a heat gun. With slight frosts, the method works quite well, but you will have to spend time and a significant amount of electricity.
The film has good thermal conductivity, although it does not let air through, so it is better to build a shelter in several layers.
