If you've decided it is time to change or clean the gas filter, there are a couple of basic types which are all easily serviced or replaced. Most motors utilize some form of an inline filter either between the gas tank and pump or between the pump and carburetor(s) or gas injection vapor separator tank.
Some inline filters are solid metal or clear plastic housings which are clamped in the middle of two gas supply hoses. This style is easily removed and replaced by undoing the clamps and carefully pulling the hoses free of the filter inlet and outlet nipples.
Other inline filters consist of a 2 piece plastic or metal housing where a gas filter bowl can be removed from a filter cap. The bowl often threads into position or is secured by a knurled knob which can be loosened by hand in order to remove the bowl. Inside the bowl or cap of this style filter you'll find a removable filter screen. If the screen is not damaged it can be rinsed in solvent and air dried (or VERY carefully blown dry using low-pressure compressed air). When in doubt, this type of filter screen is easily and inexpensively replaced.
Before checking the gas pump, make sure you've got clean gas filter/water separators. Finally, many boats and some motors are rigged using a disposable spin-on gas filter or fuel filter and water separator. These filters resemble automotive oil filters and are removed or installed in exactly the same fashion. Often you'll want a strap or cap wrench for removal, as they tend to get stuck in place after a season's use. Once unthreaded, you'll normally find a small rubber gasket which again looks just like the gasket on an oil filter. Before installing a replacement spin-on gas filter, be sure to lubricate the rubber gasket with a small dab of engine oil (again, just like with a spin-on oil filter) to ensure a good seal and to help make sure the filter comes off with ease next time you need to replace it.
iboats.com carries an extensive line of gas filters and water separators.
Marine Fuel Filters How-Tos
Efficiency in Water Separation for the Marine Industry
Why is the Racor water separation fuel system so much better than other systems?
In the marine industry, water is an enemy to boating engines, parts, hardware and all materials on the water. It is critical to use only the best water separation system for keeping particulates from your fuel, thus safe-guarding and prolonging the life of your engine.
Racor water separation filtration systems rank top to any other marine water separation system. Why would you risk using anything else? In the graph below you can see that a racor separation system maintains the highest removal efficiency, over a longer duration, than any other system on the market.
Why is Racor so much better that other products? It uses the highest quality Aquabloc media, which meets or exceeds efficiency requirements for OEM fuel injection systems. In its filtering systems it uses the highest quality automotive grade gaskets and seals. Its materials are temperature rated for a wide range of temperatures - from minus 40 degrees to plus 255 degrees Fahrenheit. They are also certified against the casting cracking due to extreme climatic and vibration conditions.