The root cause of insufficient power, difficult starting or unstable operation of small gasoline engines often lies in the fuel system. This system is responsible for providing clean, sufficient and proportionally correct mixed gas. Any malfunction in any link will directly affect the power.
The primary reason is the issue of oil quality. Using poor-quality gasoline or gasoline that has been stored for more than three months will cause its light components to evaporate, leading to the coagulation of gum. These gums can clog precision components such as fuel filters and carburetor orifice, just like blocked blood vessels, causing poor or even interrupted fuel supply, and the engine naturally loses power.
The core fault point lies in the carburetor. As the “heart” of the fuel system, carburetor failure is often manifested as:
1. Blockage: It is the most common problem. Dust and gummy substances can clog the main fuel supply hole and idle fuel supply hole, resulting in insufficient fuel supply, overly lean mixture, and engine poweriness and overheating at high speeds.
2. Improper adjustment: If the mixture is too lean (with less oil and more gas) or too rich (with more oil and less gas), complete combustion cannot be achieved, which respectively leads to insufficient power, backfire during acceleration or black smoke, and a sharp increase in fuel consumption.
3. Wear of the fuel needle: Wear of the fuel needle in the carburetor can lead to uncontrolled fuel supply, resulting in overly rich mixture.
4. Water ingress and poor sealing: Water in the fuel tank can cause rust and blockage inside the carburetor. In addition, if the interface between the carburetor and the intake pipe is not sealed tightly, additional air will be drawn in, resulting in an overly lean mixture.
In addition, the supporting components should not be overlooked either. A clogged vent hole on the fuel tank cap will create negative pressure inside the fuel tank, preventing the fuel from flowing smoothly into the carburetor. If the fuel filter has not been replaced for a long time and gets clogged, it will also cut off the fuel passage. If the fuel pipeline ages and cracks, air will leak in, disrupting the stability of fuel supply.
Therefore, when a power failure occurs, the fuel system should be given priority for inspection. A systematic check and cleaning should be carried out, from the quality of the fuel to the condition of the carburetor.
HONDA