Outboard motors come in two styles: carbureted engines and electric fuel injected engines. There are different pros and cons to both, but both also work in different manners. Fuel injection outboard motors (also called EFI) are much more common these days, but many older boats still have engines with carburetors. A carburetor works by blending the precise amount of air and fuel into the outboard to drive the pistons. A vacuum pulls air down through the carburetor, and mixes it with fuel. Carburetors do require maintenance and regular cleaning, as the air can actually dry out the fuel in the reservoir, leaving a gummy substance which thickens the gas and doesn’t move efficiently through the carburetors small parts. In some instances, it’s easier to replace the boat’s carburetor than clean it. Fuel injection motors tend to be more costly upfront, but they are also more fuel efficient and also release fewer emissions. An added plus is that they require less maintenance than carburetors—but that doesn’t mean they’re maintenance free. Fuel lines may need replacement, or boat fuel injector cleaner can make sure none of the parts are gumming up with thick fuel and keep the engine running smoothly for longer. Use our Marine Engine Parts Selector Tool to find the right engine parts for your boat.