How To Clean A Mechanical Fuel Pump

Installing a new fuel pump in an old fuel tank can cause premature wear, or worse, cause a brand new pump to fail completely. That's because dirt, debris, and contamination stuck in the fuel tank can clog the brand new strainer, which was most likely the cause of the previous faulty fuel pump.

A clogged fuel strainer will starve the pump of fuel and prevent the fuel system from receiving the correct amount of fuel and/or optimal fuel pressure. This could prematurely wear and damageyour newly installed fuel pump, as well as other parts in the vehicle's fuel system. In severe cases of contamination, debris buildup on the fuel sending unit can cause inaccurate fuel level readings in today's fuel-injected systems.

Symptoms of a clogged fuel filter include: trouble starting, sputtering, hesitation, backfiring, loss of power when accelerating, poor fuel efficiency, and/or the engine not starting. And if you plan on storing your vehicle for months at a time, consider adding a fuel additive to the tank. This will help the fuel stay fresh by preventing fuel separation in the tank.

If you are replacing your fuel pump, consider cleaning your fuel tank to protect the longevity of your new fuel pump. We recommended draining and removing the tank from the vehicle and following the steps below for the best cleaning method.

Recommended: 10 steps on how to clean a fuel tank

Before you clean, think safety first

Always have a Class B fire extinguisher readily available.
Work in a well-ventilated area away from open flames and anything that could cause a spark.
Make sure to wear safety glasses and any other safety protections needed while performing fuel system repairs.
Disconnect the ground cable from the vehicle's battery before performing any operation that involves fuel, fuel tank, or fuel lines.
Properly relieve the system's fuel pressure before any repairs are performed. Please refer to the OE service manual.
Follow local guidelines for the proper disposal of hazardous material.

10 steps on how to clean the fuel tank

Drain fuel tank into an approved container
Clean rust and debris from the top of the tank
Remove the fuel pump
Swirl gas tank— Pour out remaining gas and debris
Clean the tank interior with a low-suds soap and water mixture*
Swirl cleaning solution inside the tank
Drain tank and dry with compressed air and/or a lint-free cloth
Visually inspect the fuel tank and replace the tank if damaged
Confirm tank is completely dry (may take approximately 30 minutes)
Replace the fuel with fresh fuel

*For your convenience, Delphi Technologies Aftermarket offers a Fuel Tank Cleaning Kit (FC01) that includes a low-suds cleaning solution specifically designed to easily treat and rinse up to a 40-gallon capacity fuel tank.

What if it's too difficult to drop the fuel tank?

Dropping the fuel tank might not be the best option for those who have a saddle-style fuel tank and/or drive an all wheel drive, 4 wheel drive, or rear wheel drive vehicle because the drive shaft is in the way. And sometimes, removing the exhaust just to get to the fuel tank might be more hassle than it's worth. We know everyone might not drop the tank, so we created a new cleaning solution— The fuel tank cleaning wand. Check it out!

5 steps on how to use the fuel tank cleaning wand

Clean rust and debris from the top of the tank
Remove the fuel pump
Attach new fitted microfiber wipe to wand (included with the cleaning wand)
Wipe around inside walls and bottom of the fuel tank
If the wipe comes out dirty, replace with a new wipe and repeat until the wipe is clean**

**Please note: If the microfiber wipe is considerably dirty after multiple cloths are used, the fuel tank will need to be dropped for either a deeper clean or replacement with a new fuel tank.

Find ourFuel Tank Cleaning Kit (FC01) and Fuel Tank Cleaning Wand (FC02) in our online catalog or contact your Delphi Technologies sales representative for more information.

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