What is the reason why the car oil extraction hose cannot be inserted?
2 Answers
There is a ping-pong ball with a diameter of about 2CM in the oil pipe, so the pipe cannot be directly inserted. You can use a slightly rigid hose with a diameter of 4-6 mm, rotate it while inserting and pulling, squeeze it in from the side of the ping-pong ball, and then you can directly insert the pipe. Fuel tank structure: Because the fuel delivery pipe of many cars is connected to the side of the fuel tank, if the oil extraction pipe is too hard, even if it is inserted into the fuel tank with great difficulty, the pipe will be parallel to the gasoline liquid level and cannot reach the fuel tank liquid level, so oil extraction is still impossible. Fuel tank anti-overflow check valve: To prevent gasoline from leaking from the fuel filler port when the vehicle rolls over or tilts, a check valve is designed at the connection between the fuel delivery pipe and the fuel tank. Its function is to ensure that gasoline can enter the fuel tank from the fuel delivery pipe, but the gasoline in the fuel tank cannot flow back to the fuel delivery pipe. This check valve is actually very simple, and most check valve structures will not cause too much interference to the pipe insertion for oil extraction.
Once I encountered this issue and found that the oil extraction hose couldn't fit into the fuel filler neck mainly because the hose diameter was too large, possibly exceeding the inlet size of the fuel pipe. Modern vehicles are designed with anti-siphon valves or curved pipes to prevent accidental fueling with low-quality fuel or fuel theft, making it impossible to insert an overly thick hose. Additionally, if the fuel filler neck is clogged with dirt or blocked by foreign objects, it can also hinder the hose. I've tried using a thinner hose or slightly lubricating the tip, which allowed it to slide in easily. However, forcing it in may damage internal components, leading to bigger problems. Therefore, it's advisable to first measure whether the hose size matches, clean the fuel filler neck, and if it still doesn't work, take it to a professional repair shop for inspection. Safety first—don't rush to try again, as it could cause a fire or fuel leakage.
