Method for operating internal combustion engine with a fuel composition

Abstract

A method for preventing combustion chamber deposits from causing start-failures in an internal combustion engine comprises operating the engine with a fuel composition that contains a normally liquid fuel and a nitrogen-containing detergent that includes a polyetheramine; a Mannich reaction product of a hydrocarbyl-substituted phenol, an aldehyde and an amine; or a mixture there. The method is effective in preventing start-failures in multi-valve, low friction, spark-ignited engines.

1 . A method for preventing combustion chamber deposits from causing start-failures in an internal combustion engine, comprising: 
 operating the engine with a fuel composition comprising a normally liquid fuel; and    a nitrogen-containing detergent comprising a polyetheramine; a Mannich reaction product of a hydrocarbyl-substituted phenol, an aldehyde, and an amine; or a mixture thereof.    
     
     
         2 . The method of  claim 1  wherein the fuel composition comprises the normally liquid fuel; and a polyetheramine.  
     
     
         3 . The method of  claim 1  wherein the internal combustion engine is a multi-valve, low friction, spark-ignited engine; and the fuel is a gasoline.  
     
     
         4 . The method of  claim 3  wherein the polyetheramine is represented by the formula RO(AO) m R 1 NR 2 R 3 ; wherein R is a hydrocarbyl group of about 8 to about 30 carbon atoms; A is an alkylene group having 2 to 6 carbon atoms; m is a number from 1 to about 50; R 1  is an alkylene group having 2 to 6 carbon atoms; and R 2  and R 3  are independently hydrogen, a hydrocarbyl group or —[R 4 N(R 5 )] n R 6  wherein R 4  is an alkylene group having 2 to 6 carbon atoms, R 5  and R 6  are independently hydrogen or a hydrocarbyl group, and n is a number from 1 to 7.  
     
     
         5 . The method of  claim 4  wherein the polyetheramine is represented by the formula RO[CH 2 CH(CH 3 CH 2 )O] m CH 2 CH 2 CH 2 NH 2 ; wherein R is an aliphatic group or alkyl-substituted phenyl group of about 8 to about 30 carbon atoms; and m is a number from about 12 to about 30.  
     
     
         6 . The method of  claim 5  wherein the polyetheramine is represented by the formula CH 3 CH(CH 3 )[CH 2 CH(CH 3 )] 2 CH(CH 3 )CH 2 CH 2 O[CH 2 CH(CH 3 CH 2 )O] m CH 2 CH 2 CH 2 NH 2 ; wherein m is a number from about 16 to about 28.  
     
     
         7 . The method of  claim 3  wherein the Mannich reaction product is prepared from an alkylphenol derived from a polyisobutylene, formaldehyde, and an amine that is an alkylenediamine or a dialkylamine.  
     
     
         8 . The method of  claim 7  wherein the alkylenediamine is ethylenediamine.  
     
     
         9 . The method of  claim 7  wherein the dialkylamine is dimethylamine.  
     
     
         10 . The method of  claim 3  wherein the fuel composition further comprises one or more additional additives.  
     
     
         11 . The method of  claim 3  wherein the fuel composition is prepared by adding the nitrogen-containing detergent as a bulk treatment to the fuel wherein the amount of the detergent in the fuel composition is 100 to 1,000 ppm by weight.  
     
     
         12 . The method of  claim 3  wherein the fuel composition is prepared by adding the nitrogen-containing detergent as an aftermarket treatment to the fuel wherein the amount of the detergent in the fuel composition is 1,000 to 10,000 ppm by weight.  
     
     
         13 . The method of  claim 12  wherein the nitrogen-containing detergent is a polyetheramine.  
     
     
         14 . The method of  claim 13  wherein the engine is operated under a clean-up cycle.  
     
     
         15 . The method of  claim 14  wherein the clean-up cycle generates engine speeds of at least 3,000 rpm.