| abstract |
A fuel composition for internal combustion engines, and more particularly, a fuel composition for internal combustion engines containing less than about 0.5 gram of lead per gallon of fuel is described. The fuel provides acceptable valve seat protection in engines designed to operate on leaded or unleaded fuels. Ordinarily, leaded fuels contain components to reduce deposits within the engine cylinders which unleaded fuels do not. As leaded fuels become unavailable, some refiners will add valve protecting components to the unleaded fuels to satisfy the leaded market. Such fuels will then potentially cause an increase in the octane requirement. This invention deals with polybasic carboxylate additives having valve seat protection properties which avoid or minimize the octane requirement increase. |