Composition for cleaning an internal combustion engine

Abstract

A formulated composition is disclosed which is designed to clean baked-on, carbonized sludges and varnish deposits from the upper cylinder surfaces of automobile, motorcycle and truck engines. The product is comprised of a mutually synergistic solution of selected cyclic compounds, aliphatic amines and water, preferably dissolved in a hydrocarbon or hydrocarbon and aliphatic lower alcohol fuel base, to which minor materials may optionally be added. The solution or base product may be placed in a pressure resistant (aerosol) container pressurized with a compressed gas, such as nitrogen gas. A preferred embodiment of the invention utilizes a synergistic solution of N-methyl-2-pyrrolidone, n.butylamine and de-ionized water, with these ingredients present at certain ratios. This solution is dissolved in either mixed iso-(C.sub.7, C.sub.8)-hydrocarbons or a combination of such hydrocarbons with a minor amount of isopropanol, to which up to about 10% by weight of other optional ingredients may be added. The container may then be sealed with a suitable valve and pressurized. The provided compositions are adequately compatible with the fluorosilicones gasket compositions. By limiting the concentration of the N-Methyl-2-pyrrolidone to 10% of the total, and by changing the n.butylamine (or similar simple primary or secondary amines) to not more than 10% of a tertiary amine, such as triethylamine, outstanding cleaning ability is obtained. When formulae of the subject invention are injected into an engine over a period of several minutes, very significant removal of any deposited contaminants occurs, resulting in smooth and efficient operation and much lower levels of unburned hydrocarbon fuel, carbon monoxide, and other recognized air pollutants. The advantages conferred by a single application of the subject composition are sustained for many thousands of miles of automobile operation.