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RE: Petrol home storage
Its still very wise and prudent to treat stored fuel with stabilisers like STA-Bil, it stops the volatiles breaking down , stops alagae forming, stops water droplets forming etc I also use Cetane boosters in my stored diesel. Modern petrol is very unstable and if left in normal petrol station tanks breaks down in about 8 weeks, You need to keep it in smaller sealed containers that cannot let the fuel react with air, like Jerrycans.
Cetane Boosters
Cetane boosters only improve cold starting on diesel engines due to increase of flamability of the mixture at lower pressure and temperature. It has been proven that no effect on the power of the engine is attained once the engine is at normal operating conditions.
There are a number of engine performance characteristics that are generally recognized as important. Their relative importance depends on engine type and duty cycle (truck, passenger car, stationary generator, marine vessel, etc.).
starting ease low wear (lubricity)
sufficient power low temperature operability
low noise long filter life (stability)
good fuel economy low emissions
Engine design, by far and away, has the greatest impact on most of these characteristics. But since the focus of this publication is fuel, this chapter will discuss how they are affected by fuel properties.
STARTING
When a cold diesel engine is started (cold start), the heat of compression is the only energy source available to heat the gas in the combustion chamber to a temperature that will initiate the spontaneous combustion of the fuel (about 750°F [400°C]). Since the walls of the combustion chamber are initially at ambient temperature rather than operating temperature, they are a significant heat sink rather than a heat source. And since cranking speed is slower than operating speed, compression is also slower, which allows more time for the compressed air to lose heat to the chamber walls. (A glow plug provides an additional source of heat in indirect-injection diesel engines.) A fuel that combusts more readily will require less cranking to start an engine. Thus, if other conditions are equal, a higher cetane number fuel makes starting easier. As the compression temperature is reduced by variables like lower compression pressure, lower ambient temperature, and lower coolant temperature, an engine requires an increasingly higher cetane number fuel to start easily. Research indicates that fuels meeting the ASTM Standard Specification D 975 cetane number requirement of a minimum of 40 provide adequate cold starting performance in modern diesel engines. At temperatures below freezing, starting aids may be necessary regardless of the cetane number of the fuel. Even after the engine has started, the temperatures in the combustion chamber may still be too low to induce complete combustion of the injected fuel. The resulting unburned and partially burned fuel is exhausted as a mist of small droplets that is seen as white smoke (cold smoke). This situation normally lasts for less than a minute, but the exhaust is irritating to the eyes, and can be objectionable if a number of vehicles are started together in an enclosed space. A fuel with a higher cetane number can ameliorate the problem by shortening the time during which unburned fuel is emitted to the atmosphere.
POWER
Power is determined by engine design. Diesel engines are rated at the brake horsepower developed at the smoke limit.1 For a given engine, varying fuel properties within the ASTM D 975 specification range does not alter power significantly. For example, in one study seven fuels with varying distillation profiles and aromatics contents were tested in three engines. In each engine, power at peak torque and at rated speed (at full load) for the seven fuels was relatively constant. However, if fuel viscosity is outside of the D 975 specification range, combustion may be poor, resulting in loss of power and fuel economy.
NOISE
The noise produced by a diesel engine is a combination of combustion noise and mechanical noise. Fuel properties can affect only combustion noise. In a diesel engine, the fuel ignites spontaneously shortly after injection begins. During this delay, the fuel is vaporizing and mixing with the air in the combustion chamber. Combustion causes a rapid heat release and a rapid rise of combustion chamber pressure. The rapid pressure rise is responsible for the diesel knock that is very audible for some diesel engines. Increasing the cetane number of the fuel can decrease the amount of knock by shortening the ignition delay. Less fuel has been injected by the time combustion begins and it has had less time to mix with air. As a result, the rapid pressure rise, along with the resulting sound wave, is smaller. One design approach to reducing combustion noise is to shape the injection-setting the rate slow at first and then faster - to reduce the amount of fuel entering the cylinder during the ignition delay period. Another is to use indirect-ÂÂinjection
FUEL ECONOMY
Here again, engine design is more important than fuel properties. However, for a given engine used for a particular duty, fuel economy is related to the heating value of the fuel. Since diesel fuel is sold by volume, fuel economy is customarily expressed as output per unit volume e.g., miles per gallon. Therefore, the relevant units for heating value are heat per gallon (Btu per gallon). Heating value per gallon is directly proportional to density when other fuel properties are unchanged. ASTM specifications limit how much the heating value of a particular fuel can be increased. Increasing density involves changing the fuel's chemistry - by changing aromatics content - or changing its distillation profile by raising the initial boiling point, the end point, or both. Increasing aromatics is limited by the cetane number requirement (aromatics have lower cetane numbers [see Figure 4-7]); changing the distillation profile is limited by the 90% distillation temperature requirement. Combustion catalysts may be the most vigorously promoted diesel fuel aftermarket additive (see Chapter 7). However, the Southwest Research Institute, under the auspices of the U.S. Transportation Research Board, ran back-to-back tests of fuels with and without a variety of combustion catalysts. These tests showed that a catalyst usually made "almost no change in either fuel economy or exhaust soot levels."2 While some combustion catalysts can reduce emissions, it is not surprising that they don't have a measurable impact on fuel economy. To be effective in improving fuel economy, a catalyst must cause the engine to burn fuel more completely. But there is not much room for improvement. With unadditized 3 fuel, diesel engine combustion efficiency is typically greater than 98%. Ongoing design improvements to reduce emissions are likely to make diesel engines even more efficient.
STA-BIL Fuel Stabiliser Cars Boats Lawnmowers Petrol
Gold Eagle Sta-Bil Fuel Stabilizer is a fuel additive that keeps fuel fresh for quick, easy starts after periods of storage. Designed for all 2-cycle and 4-cycle gasoline engines, Sta-Bil Fuel Stabilizer eliminates the need to drain fuel before storage in order to protect your engine from the gum, varnish, rust, and corrosion that can afflict engines after gasoline left in the tank has broken down. It also prolongs the life of an engine by removing water from gas tanks, and cleans carburetors and fuel injectors. The solution works safely and effectively in all gasoline blends, including ethanol-blended fuel up to E85.
Protect Gas Engine During Storage without Draining the Tank
Sta-Bil Fuel Stabilizer is America's top selling fuel stabilizer - and for good reason, it works. It's hard to believe, but fuel left in the tanks of a stored vehicle can begin to break down in as little as 30-60 days causing gum, varnish and corrosion to build up in the fuel lines and engine. One traditional solution to this problem is to drain the tank before storage, but this is time-consuming and messy. It can also be counter productive since it is very difficult to get all of the fuel out of a tank and leaving the walls of your fuel tank exposed during storage can invite corrosion in the presence of moisture, especially in fuels containing ethanol.
Protection against corrosion and gumming during storage and everyday use for gasoline engines.
View larger.
Sta-Bil Fuel Stabilizer does away with all this by inhibiting fuel break down, allowing you to leave fuel in your stored vehicle worry-free. It also cleans carburetors and fuel injectors in the event of existing gumming up of fuel systems prolonging engine life and ensuring quick, easy starts after storage is over and the covers come off your ride.
New Improved Formula Protects Against Ethanol Additives
No longer just for cars being placed into storage, the new formula of Sta-Bil Fuel Stabilizer also makes it the perfect product to be used at every fill up in all vehicles and equipment to protect against corrosion caused by today's ethanol-blended fuels. Ethanol additives in modern fuels are intended to minimize carbon dioxide emissions, but they can also create problems in the form of corrosion and clogged fuel systems that can dramatically impact performance. Ethanol is optimally soluble in gasoline under the right conditions, but when temperatures become too hot or too cold the additive can become unstable, drawing moisture into your gas tank. This addition of moisture into the fuel mix can lead to phase separation, a condition in which total saturation of the fuel results in the ethanol and water separating from the gas mixture, and coming to rest near the bottom of the tank. If the level of this fuel-depleted liquid mixture is allowed to accumulate it not only will take up precious space in your fuel tank, but it may also be injected into your engine affecting performance and potentially creating serious problems. In addition, if significant water remains in your tank the moisture can cause rust and corrosion, or contribute to the gumming up of your fuel system. Sta-Bil Fuel Stabilizer puts an end to this in all 2-cycle and 4-cycle engines. Just add a few penny's worth of Sta-Bil Fuel Stabilizer to your tank each time you fill up and you could be saving yourself hundreds of dollars in repair costs in the long run.
Key Features
America's top selling fuel stabilizer keeps fuel fresh for quick, easy starts after storage
Removes water to prevent corrosion and cleans carburetors and fuel injectors
Protects engine from gum, varnish, rust, and corrosion
Prolongs engine life
Eliminates the need to drain fuel before storage
Works safely and effectively in all gasoline's including ethanol-blended fuel up to E85
For all 2-cycle and 4-cycle gasoline engines
32-oz bottle treats up to 80 gallons of fuel
WINTER DIESEL
NR
Basically this explains why you need to buy your diesel for storing and caching in the winter.
EN590
BS EN 590:2004 (which supersedes BS EN 590:1999) lays down the maximum "cold filter plugging point" (CFPP, the temperature at which the fuel won't pass through a fuel filter) for UK diesel. Pretty much every UK forecourt sells diesel certified to BS EN 590.
- for diesel on sale between 16th March and 15th November, the max CFPP is -5 degrees C
- for diesel on sale between 16th November and 15th March, the max CFPP is -15 degrees C
If you've got problems with your diesel waxing, then either:
- it's been a lot colder than you realise
- you're running on summer diesel in the winter
- you're running on heating oil or something else which isn't "diesel"
- your local garage is being very naughty and needs reporting to Trading Standards
Or, of course, you might have bought a stockpile of 2000 litres of diesel back in June when it was cheap ...
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