These are the basic components of the dual-fuel system. Liquid fuel delivered from the tank travels through a bulkhead fitting and arrives at the small blue filter. Attached to the filter, an electrically operated solenoid permits fuel flow when in propane mode. The liquid enters the regulator and is heated by the engine's coolant flow. The removal of ambient pressure and the heat from the regulator convert the liquid propane to gas, which travels along the large black hose to the mixer. The mixer is mounted on top of the carburetor where a cable-actuated diaphragm delivers propane gas.