Dual-Fuel Systems

Dual-Fuel systems (sometimes called Bi-Fuel) are vehicles that have been converted to operate on gasoline and can be alternately switched to run on CNG. Some of these vehicles are also set up to operate on gasoline and can be alternately switched to run on propane.

These vehicles use two carburetors or injection systems, the gasoline carburetor or injection system (generally the factory carburetor or injection system is maintained) and the LPG or CNG carburetor (also called the mixer) or injection system. Many of these units have the alternate fuel carburetor mounted on top of the factory carburetor. Some of the newer mixers are capable of being installed inside the thermostatic air cleaner therefore, retaining use of the TAC. Mixers and their regulators are generally designed for a specified engine displacement range. For example, one particular model type may be usable only on engines ranging in displacement of 200 cubic inches to 350 cubic inches (this also applies to CNG and LNG), so be sure the proper mixer and regulators are installed. You should also test these vehicles using the fuel the customer has the vehicle operating on when he pulls into the shop unless your state requires otherwise. This is because the system not in use may have deteriorated due to lack of use and may be dangerous to operate.