From the Fleece Team: Protect your new fuel system investment: Why fuel tank inspection matters before installation.

Steps to Complete:

1. Drain the fuel tank into a clean bucket or pail. 
Some fuel tanks are outfitted with a drain plug that can be pulled to drain the fuel. In applications where the tank does not have a drain plug, a siphon may be required. Inspect the condition of the fuel removed from the tank and determine whether filtration prior to use is necessary. Fuel drained from the vehicle may be contaminated and must be handled and disposed of properly. Collect all drained fuel in an approved container. Do not discharge fuel onto the ground, into drains, or with household waste. Dispose of contaminated fuel through an authorized hazardous waste or recycling facility in accordance with all applicable local, state, and federal regulations.

 

2. Remove the fuel tank from the truck.  
Use a transmission jack or floor jack to support the tank during removal. Remove all appropriate connections from the fuel tank such as the electrical connector to a stock sending unit, fuel lines, or the fill tube.

3. Clean the top of the fuel tank 
To prevent any contamination after the internal cleaning of the fuel tank is complete, clean the top of the fuel tank. Using a brush or compressed air, sweep off any debris sitting on the top of the tank. Then with a clean shop rag wipe down the top surface of the tank, paying special attention to the top of the stock sending unit.  

4. Remove the stock sending unit and begin the internal inspection of the fuel tank.  
Inspect the inside of the fuel tank and the condition of any remaining fuel. Once the condition of the remaining fuel is noted it can be removed for reuse later or discarded. This step will remove the first layer of water or sludge in the tank if it is present. 

5. Clean the fuel tank. 
Once the tank is empty, begin mechanically cleaning the inside of the tank. Mechanical cleaning can be done using plastic bristled brushes and scrapers. These will physically remove any debris or residue stuck to the inside of the tank. In cases of microbial contamination, scrubbing the tank is especially important due to the thick film that algae forms on the tank wall. Scrubbing physically loosens and removes this layer.  

After scrubbing the tank, flush it with clean diesel fuel or an appropriate cleaning solution. Flush the tank several times to remove any debris created during scrubbing. Once the fluid runs clear, and is free of debris, dry the fuel tank thoroughly. This can be done with a lint-free cloth, or the tank can be allowed to air dry.  The tank must be completely dry before reinstallation as any residual moisture can encourage microbial growth.  

Apply a biocide treatment if microbial contamination was present initially, or if no microbial growth was present, the use of a fuel treatment is recommended to prevent this type of contamination.

6. Post-cleaning and Long-term Maintenance 
Reassemble the fuel system and replace all fuel filters. After cleaning a fuel tank, old filters could clog shortly afterward, especially if microbial growth is the cause for contamination. Changing the filters after cleaning the tank will prevent clogging and keep debris from reaching vital parts of the vehicle's fuel system. 

Long-term prevention for contamination involves minimizing water in the fuel system, and being mindful of fuel sources and the tools used for filling. Keeping the fuel tank as full as possible is one of the most effective ways to minimize water in the fuel system. This limits the amount of air in the tank and prevents condensation from forming. In addition to regularly filling the fuel tank, water collection can also be minimized by regularly draining the water separator. This allows any water at the bottom of the system to drain. For microbial concerns, it is also recommended to use a regular fuel treatment to prevent the growth of algae. When filling your fuel tank, try to source fuel from service stations that are known to have high traffic, and avoid sourcing fuel from farm or job site tanks. This will ensure your vehicle always has a fresh supply of fuel and reduces the possibility of receiving contaminated fuel from the service station itself. Inspect and 
clean all fuel jugs before use. 

When installing a PowerFlo® or SureFlo®, taking the time to perform this inspection and remove contaminants helps protect your newest fuel system investment. If left unaddressed, contamination can find its way into your new SureFlo sending unit or PowerFlo lift pump, which can lead to accelerated wear and tear on the part or premature failure.