What are the reasons why the fuel pump of a diesel vehicle cannot pump oil?
2 Answers
Here are the reasons why the fuel pump of a diesel vehicle cannot pump oil and the inspection methods: 1. The one-way valve is not tightly sealed: The pressure cannot be built up because one or both of the one-way valves are not tightly sealed, causing leakage. 2. Air is sucked into the fuel transfer pump: There is a seal failure in the low-pressure pipeline between the fuel transfer pump and the fuel tank, causing air to be sucked into the fuel transfer pump. 3. Inspection method: You can remove the inlet pipe of the hand fuel pump, then connect another pipe to a bucket with some oil to see if oil comes out. If oil comes out, clean the fuel line and check if there is any air leakage in the inlet pipe. If no oil comes out, there is a problem with the hand fuel pump.
I've been driving a diesel car for ten years. Last time, the fuel pump failed to pump oil, and the car suddenly stalled on the highway, which scared me to death. The most common reason is that the fuel filter is too clogged, with accumulated dust blocking the fuel flow. It could also be that the fuel pump itself is broken, worn out, or aged, leading to insufficient pressure. In my case, it turned out to be a faulty fuel transfer pump, which couldn't deliver fuel properly, causing the entire system to fail. Another possibility is air entering the system, creating an airlock that obstructs fuel flow. Other issues like a leaking fuel line, an empty fuel tank, or poor electrical connections can also cause the pump to stop working. You must pull over immediately to check, otherwise, it could lead to an accident. When I got it repaired, replacing the filter fixed the issue. I recommend regular maintenance and cleaning of the filter to avoid such problems.
