Use of additives for improved engine operation

Abstract

Engine operation is improved by means of detergent additives. An additive comprising, or obtainable by admixing, A or B or both wherein: A is a metal-containing detergent, and B is a non metal-containing detergent, is used in an internal combustion engine lubricated by means of a separate lubricating oil system, to enhance the properties of the lubricating oil of the engine through entrainment therein the combustion chamber during operation of the engine.

1 . The use of an additive comprising, or obtainable by admixing, A or B or both wherein: 
 A is a metal-containing detergent, and    B is a non metal-containing detergent,    in an internal combustion engine lubricated by means of a separate lubricating oil system, to enhance the properties of the lubricating oil of the engine through entrainment therein in the combustion chamber during operation of the engine.    
     
     
         2 . The use of  claim 1  wherein the engine is a four stroke engine.  
     
     
         3 . The use of  claim 1  or  claim 2  wherein the additive is supplied to the combustion chamber entrained in the fuel.  
     
     
         4 . The use of any preceding claim wherein the additive is preferentially absorbed into the lubricating oil lining the combustion chamber.  
     
     
         5 . The use of any preceding claim wherein the additive enhances the viscosity characteristics of the lubricating oil upon entrainment therein, reducing the oil consumption of the engine.  
     
     
         6 . The use of any of  claims 1  to  4  wherein the additive enhances the deposit control characteristics of the lubricating oil upon entrainment therein.  
     
     
         7 . The use of the preceding claims wherein the engine is a diesel engine.  
     
     
         8 . The use of any preceding claim wherein component A is a calcium-containing detergent.  
     
     
         9 . The use of any preceding claim wherein component B is a polyisobutylene succinimide.  
     
     
         10 . The use of  claim 9  when dependent upon  claim 8.