In the previous gasoline engine, the engine oil was supplied to the carburetor through the oil pump, and then the carburetor was vaporized in proportion and injected into the cylinder to be ignited by the spark plug.

That is to say, the fuel tank, the gasoline filter, the oil pump, the carburetor, and finally the cylinder.

The intermediate oil pump is driven by a camshaft.

At present, the gasoline engine has an oil absorber to directly supply gasoline to the electronic fuel injection equipment in the fuel tank, and electronically control the fuel injection and ignition. That's about it. I hope I can help you.