Technician A says the fuel tank needs to be flushed before a new fuel pump is installed. Technician B says the fuel filter will capture the dirt and debris.
Who is correct? Technician A or B?
Fuel pump replacement comebacks can be costly and can hurt your reputation. One of the leading causes of failure is the tank. If a vehicle gets 20 miles to the gallon, then more than 5,000 gallons of gas (from many stations) will go through the tank in 100,000 miles. During this time, sediment, rust and debris from the pump can find its way into the tank. Removing all contaminants is critical. If possible, have the tank cleaned. Your goal in cleaning the tank is to restore the environment inside thetank to the same state it was in when they put fuel in before it drove off the assembly line.
If you think the new sock or strainer on the full pump will catch all of the bad stuff, you are wrong. The typical sock or strainer is designed to catch particles that are between 50-100 microns in diameter. Forty microns is the size of a human hair. A typical inline fuel filter can catch particles as small as 10 microns. The sock also has a limited capacity due to its small surface area.
But! Always install a new filter. Sounds simple, but it is often forgotten. The old filter can restrict flow and make the new pump work harder. This makes for a hotter running pump that fails sooner. This video is sponsored by Carter.