VIDEO: Oil Pump Lost Its Prime

VIDEO: Oil Pump Lost Its Prime

Can you answer this ASE G1 test prep question? This video is sponsored by FRAM.

After an engine oil and filter service, a technician can’t get the oil pressure warning light to go out after 10 seconds of running and is not in the correct range.
What is the MOST likely cause?
A) The oil filter
B) Wrong viscosity oil installed
C) All the oil has run out of the pump
D) Air trapped in the pressure sensor

The answer is C.

Although not a common occurrence, it is very possible that the oil pump may lose its prime during the oil change. When the used motor oil is drained from the engine the oil may also drain from the oil pump pickup tube and possibly from the oil pump itself. When new motor oil is installed the pump’s pickup tube inlet again becomes submerged, trapping air in the tube on the suction side of the oil pump. Sometimes this problem can be avoided by limiting the time the oil is drained. The trapped air will cause cavitation of the pump and prevent it from producing oil flow and pressure. Many techs tend to blame this on the oil filter and assume that the filter is blocking the flow of oil. The point being made is the oil filter was not the problem and in most cases there is a simple solution.

If after the oil and filter change, the red light or low oil pressure remains for ten seconds, shut the engine off, remove the oil filter and, using an oil squirt can with the correct motor oil, squirt oil several times into the oil filter base outlet on the engine. Next, fill the filter with new motor oil and reinstall. Start the engine and check for oil pressure. In most cases, the problem will be solved. DO NOT allow the engine to run for more than ten seconds without oil pressure. Use a watch to time the ten seconds and be sure of the elapsed time. In some instances, the full ten seconds is needed for the pump to recover oil flow. If this fails, again remove the filter and crank the engine until oil spills from the engine base. DO NOT crank over ten seconds at a time. When oil spills, reinstall the oil filter, correct the oil level and restart the engine. Oil pressure should now be back to normal.

This video is sponsored by FRAM.

You May Also Like

Suspension Bushings: Role, Materials, and Wear Indicators

Regular inspection and timely replacement of worn bushings are crucial for optimal vehicle performance and safety.

Suspension bushings are vital components that connect various suspension parts such as control arms, sway bars, and shock absorbers, providing cushioning and absorbing vibrations for a smooth ride. This video covers their role in reducing noise and vibrations, maintaining proper wheel alignment, and improving handling. It explains the differences between rubber, polyurethane, and metal bushings, and highlights signs of wear like excessive movement, cracks, and unusual noises. Regular inspection and timely replacement of worn bushings are crucial for optimal vehicle performance and safety.

Randy Breaux, Group President, GPC North America, Talks to AMN Drivetime

At NAPA, “Breaux Knows” business relationships, ABCs to avoid, and serving the automotive professional.

Serpentine Belt and Drive System Maintenance

Properly maintaining the entire drive system prevents premature belt wear and system failure, ensuring customer satisfaction and vehicle reliability.

EGR Systems: Understanding Exhaust Gas Recirculation

Learn how it works, its history, and its impact on both performance and the environment.

Advanced Cooling System Technologies: Hybrid & EVs

Learn how to keep your hybrid or electric vehicle running smoothly and efficiently.

Other Posts
Do EVs Require Special Brake Pads?

Proper brake pad selection is crucial for EVs to ensure consistent stopping power and long pad life.

Five Tips for your Next Wheel Bearing Job

These practical tips are designed to save you time and frustration, ensuring a smooth, noise-free outcome for your customers.

Performance Upgrades for Drivetrains

Whether you’re increasing power or making suspension modifications, drivetrain upgrades will be next in line.

Educate Your Future Customers Utilizing AI

Discover how to generate quick, accurate explanations for repair orders and estimates, boosting your credibility and customer trust.