Coaxial liquid cooled fuel rail assembly

A liquid cooled fuel rail assembly, comprising:

• an elongate tubular fuel conduit having a longitudinal central axis, a first diameter, a first end and a second end, said fuel conduit being configured for carrying fuel and defining at least one port, each of said at least one port being configured for receiving an intake end of a corresponding fuel injector;
• a first end plug associated with said first end of said fuel conduit, said first end plug defining a first bore and a second bore therethrough, said first end plug configured for sealing said first end of said fuel conduit;
• a second end plug associated with said second end of said fuel conduit, said second end plug defining a first bore and a second bore therethrough, said second end plug configured for sealing said second end of said fuel conduit;
• a fuel inlet in fluid communication with said second bore of said first end plug;
• a fuel outlet in fluid communication with said second bore of said second end plug;
• and
• an elongate tubular coolant conduit having a second diameter, said second diameter being less than said first diameter of said fuel conduit a first segment of said coolant conduit being disposed entirely within and surrounded by said fuel conduit, said coolant conduit extending through said first bore defined by said first end plug and said first bore defined by said second end plug, said coolant conduit being configured for carrying coolant.

An inlet subassembly for a liquid cooled fuel rail, comprising:

• an inlet end plug defining a fuel inlet bore and a coolant conduit bore therethrough, said inlet end plug configured for being sealingly received within a fuel conduit;
• a fuel inlet in fluid communication with said fuel inlet bore, said fuel inlet being attached to said inlet end plug;
• and
• a coolant conduit passing through said coolant conduit bore and being attached to said inlet end plug.

A fuel injected internal combustion engine, comprising:

• a fuel conduit having a longitudinal central axis and a first diameter, said fuel conduit being configured for carrying fuel, said fuel conduit defining at least one port, each of said at least one port being configured for receiving an intake end of a corresponding fuel injector;
• a fuel inlet in fluid communication with said fuel conduit;
• a fuel outlet in fluid communication with said fuel conduit;
• and
• an elongate, tubular coolant conduit having a second diameter, said second diameter being less than said first diameter of said fuel conduit, at least a first segment of said coolant conduit being disposed entirely within and surrounded by said fuel conduit, said coolant conduit being configured for carrying coolant.