Quick replacement spark plug assembly

摘要

A two-piece spark plug includes an electrically conductive outer housing including a cylindrical member having an outer wall and an inner wall, the inner wall defining a passage through the outer housing, and a plug member releasably coupled within the outer housing and including an axial electrode and an electrically insulating insulator element encircling the axial electrode, the axial electrode having a first end for connection to an electrical source and a second end for connection within a combustion chamber, and the insulator element having a circumferential first groove and adapted to be positioned within the passage of the outer housing such that a gas-tight seal is formed between the insulator element and the inner wall of the outer housing. The two-piece spark plug further includes a firewall disposed within the first groove and in electrical communication with the outer housing, and an outer electrode in electrical communication with the firewall, the outer electrode cooperating with the second end of the at least one member of the axial electrode to form a spark gap therebetween, and wherein the firewall operates as a heat sink and transfers heat energy from the plug member to the outer housing.