Failure to start, frequent stalls and decreased power output are all common signs of a dirty fuel filter. Yamaha engines typically require fuel filter replacement at set intervals; owner's manuals provide information specific to the engine model. Other common signs of a dirty air filter may include misfires, engine hesitation or a rough idle.
Fuel filters, which keep foreign particles and contaminants from entering the engine, are typically found along fuel lines near either the engine or the fuel tank. Filters that have become dirty or clogged with debris may restrict the flow of fuel and decrease power output and engine performance. The restricted fuel flow of a dirty filter often results in frequent stalls, especially when the engine is under higher load. Dirty filters may also result in engines knocking, shaking or rattling.
Engines that are not getting enough fuel may also exhibit signs such as jerking or coughing. Dirty fuel filters are less effective at capturing and removing foreign particles from the fuel system. This can result in damage to fuel injectors and other mechanical components. Additional signs of a dirty filter can include engines that lurch or hiccup during acceleration as well a strong smell of exhaust following a balking or coughing episode.