classic valvemaster

The harmful effects of ethanol on the classics

We are not talking about immediate breakdowns, but rather a progressive degradation that can have more serious consequences such as the clogging of carburettors, fuel pumps or injectors ...


El ethanol that we find in gasoline is a biofuel, an alcohol, which has been introduced as part of a commitment by different countries to reduce the use and dependence on petroleum-derived fuels such as gasoline itself. The generation of ethanol is carried out through the fermentation of sugars of vegetable origin.

In Spain the presence of ethanol in gas stations is common using E5 and E10 fuels, which are gasoline with an ethanol content of 5% in the E5 and 10% in the E10. The new fuel labeling has made it necessary to identify their composition in pumps and vehicles. Thus, 95 octane gasoline is sold in E5, while 98 or 100 octane gasoline is sold in both E5 and E10. 

How does ethanol affect my classic?

The use of E5 or E10 fuels In an engine that has not been properly adapted, it can produce breakdowns of some relevance. The most common are in components that have rubber, plastics or silicones, since ethanol attacks these materials if they have not been designed for it. We are not talking about immediate breakdowns, but about a progressive degradation that can have more serious consequences such as the clogging of carburettors, fuel pumps or injectors.

It is also important to note that the lubricating properties of the ethanol they are inferior to those of gasoline, an important aspect for very old engines, where the use of low sulfur fuels is already a problem.

So much valve master and Valvemaster Plus protect your classic car with a proprietary formula that replaces lead for lubrication and includes the additive Etha-Guard, which counteracts the negative effects of ethanol. Let's see how it works ...

The effects of ethanol on older vehicles


El ethanol it is hygroscopic, so it draws moisture from the air. Water mixes with ethanol, But not with gasoline, so it falls to the bottom of the fuel tank and takes away some of the ethanol, this is known as partial phase separation. With enough water, the ethanol in the fuel will saturate and come out of suspension completely (phase separation).

Classic Valvemaster y Classic Valvemaster Plus contain the Etha-Guard additive: this additive counteracts moisture and stabilizes fuel. This prevents the water from separating from the fuel and settling to the bottom of your tank. This is especially important for vehicles that are parked for a long period of time, as is typical for classic cars in winter.


Another problem is that mixed fuel ethanol they can become acidic. Ethanol fuels are not acidic when they come out of the fuel pump; but nevertheless, acidity may be due to a reaction to CO2. CO2 is extremely soluble in ethanol, so, like moisture, it will be attracted from the outside. In the presence of water, it will turn into carbonic acid, effectively turning into rainwater, which is slightly acidic with a pH of 5.6.

When the pH of ethanol drops below 6.5, it can cause fuel pumps to malfunction (due to film build-up between brushes and commutator), fuel injectors to fail due to corrosion and excessive wear. cylinders. Because Etha-Guard stabilizes ethanol blend fuel in the presence of moisture, the water cannot separate from the fuel (in the first place), thus preventing the acidification process and possible damage.

Hot running

One last issue to consider is hot running. However, this is not as straightforward as it sounds, and we must look at the chemistry once more. In reality, ethanol burns at a lower temperature than gasoline. If you look at the molecular structures of gasoline and ethanol, you will see a big difference: ethanol contains an oxygen atom, while gasoline does not contain oxygen. When the gasoline-ethanol mixture is burned in the engine, the oxygen supplied by the ethanol is now added that would not be in the pure gasoline, causing the fuel-air mixture to become leaner. This can result in the engine running (running) warmer, which can be resolved by adjusting the fuel mixture to be slightly richer.

What product is suitable for my vehicle?

So much Classic Valvemaster and Classic Valvemaster Plus They should only be used in vehicles that are not equipped with a catalytic converter.

Both products contain the Etha-Guard additive and are already well known in the classic car world for offering the best protection against valve seat recession and connecting rod pitting. With the addition of Etha-Guard, Valvemaster now offers a higher level of protection to more vehicle owners. Etha-Guard Stabilizes E5 and E10 gasoline, preventing damage to your fuel system.

Classic Valvemaster Plus it also contains a friction modifier. This has the added benefit of increasing acceleration by up to 3% and increasing gasoline consumption by up to 2%. which means it pays for itself (ie the cost of this additive is recovered).

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What do you think?

Written by The Escudería

'La Escudería' is the first Hispanic digital magazine dedicated to Vintage Vehicles. We give all kinds of machinery that moves by itself: From cars to tractors, from motorcycles to buses and trucks, preferably powered by fossil fuels ...


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