The valve clearance of the gasoline engine may be too high.
The rebound of the gasoline engine is very high when started by hand. The reason is that the valve clearance of the gasoline engine is too large, so the compression is too sufficient, and the ignition timing is misaligned, resulting in late ignition. If it doesn't start smoothly, it will happen. If rebound occurs, it can be resolved by reducing valve clearance. The specific steps are as follows:
1. Disconnect the high pressure cap from the gasoline engine.
2. Remove the valve cover retaining screws.
3. Remove the valve cover.
4. Rotate the crankshaft to top dead center.
5. Use two round wrenches to adjust the valve clearance.
The characteristics of gasoline engines are high speed, simple structure, light weight, smooth operationand easy use and maintenance. Gasoline engines are widely used in cars, especially small cars.