Fuel compositions for lessening valve seat recession

A fuel composition for internal combustion engine comprising a major amount of a liquid hydrocarbon fuel and a minor, property improving amount sufficient to reduce valve seat recession when the fuel is used in an internal combustion engine of

• (A) at least one neutral hydrocarbon soluble alkali metal sulfonate wherein the sulfonate is the alkali metal salt of a sulfonic acid of the formula R.sup.1 (SO.sub.3 H).sub.r or (R.sup.2).sub.x T(SO.sub.3 H).sub.y in which R.sup.1 and R.sup.2 are each independently aliphatic groups, R.sup.1 contains at least about 15 carbon atoms, the sum of the number of carbon atoms in R.sup.2 and T is at least about 15, T is an aromatic hydrocarbon nucleus, and x is a number of 1 to 3, r and y are numbers of 1 to 4 and
• (B) at least one hydrocarbon-soluble dispersant which is an acylated, nitrogen-containing compound having a substituent of at least about 30 aliphatic carbon atoms.

An unleaded or low lead containing fuel composition for internal combustion engines comprising a major amount of a liquid hydrocarbon fuel and (A) at least one hydrocarbon soluble sodium sulfonate in an amount sufficient to reduce valve seat recession when the fuel is used in an internal combustion engine, and (B) at least one hydrocarbon soluble acylated, nitrogen-containing compound having a substituent of at least about 30 carbon atoms;

• said compound being present in the fuel in an amount to provide a weight ratio of (A) to (B) of from about 4:0.1 to about 1:4.

A process for reducing valve seat recession in an internal combustion engine which comprises adding to the fuel to be used in the engine, a composition comprising

• (A) at least one neutral hydrocarbon-soluble alkali or alkaline earth metal containing composition containing at least 8 aliphatic carbon atoms and
• (B) at least one hydrocarbon-soluble ashless dispersant.

A process for reducing valve seat recession in an internal combustion engine which comprises adding to the fuel to be used in the engine, a composition comprising

• (A) at least one hydrocarbon-soluble alkali or alkaline earth metal containing composition and
• (B) at least one hydrocarbon-soluble ashless dispersant.

A process for reducing valve seat recession in an internal combustion engine operating on a fuel containing less than about 0.5 gram of lead per liter of fuel comprising adding to the fuel to be used in the engine, a composition comprising

• (A) a neutral hydrocarbon soluble alkali metal sulfonate of the formula R.sup.1 (SO.sub.3 H).sub.r or (R.sup.2).sub.x T(SO.sub.3 H).sub.y in which R.sup.1 and R.sup.2 are each independently aliphatic groups, R.sup.1 contains at least about 15 carbon atoms, the sum of the number of carbon atoms in R.sup.2 and T is at least about 15, T is an aromatic hydrocarbon nucleus, and x is a number of 1 to 3, r and y are numbers of 1 to 4 and
• (B) at least one dispersant which is an acylated, nitrogen-containing compound having a substituent of at least about 30 aliphatic carbon atoms in an amount sufficient to reduce the valve seat recession.