How To

How to Clean a Boat Fuel Tank? | Best For Consumer

Cleaning a fuel tank should be part of your regular maintenance schedule, mainly if your boat stays out of the water for an extended period.

A tank containing muddy deposits can cause severe problems on your boat until the engine stops. And yet, with simple gestures, it is possible to avoid all these problems.

Does not the adage say that prevention is better than cure? In this article, you will discover how to clean a fuel tank on a boat. We will finish with some quick tips that will keep your tank clean for as long as possible and protect your engine afterward. Every outboard motor for canoe and Jon boat has a special fuel tank for salty water.

Why is it necessary to clean a fuel tank regularly?

The fuel used in combustion engines is a mixture of hydrocarbons. It is, therefore, an organic medium in which bacteria and fungi can grow and multiply, especially in the presence of water.

Generally, the fuel storage conditions on boats are very favorable to the development of microorganisms. Like all other forms of micro-organic life, fungi and bacteria need carbon to feed, water to germinate, and oxygen to breathe.

For this purpose, the fuel tank is a perfect medium for the development of micro-organisms. Two factors aggravate the phenomenon:

  • The tank is often placed next to the engine. The ambient temperature is, therefore, very favorable to the proliferation of microorganisms.
  • Water accumulates in the tank due to the condensation effect and the moisture absorbed by the vent. This makes the reservoir a very favorable medium for the germination of microorganisms.

Over time, bacteria and fungi settle to the bottom of the tank and form gelatinous (muddy) deposits. These deposits can pass through the pipes and clog the filter, which may impact the engine fuel supply causing a drop in power. In extreme cases, the presence of water and micro-organisms in the fuel system can cause irreparable damage to the fuel pump and injectors and cause the engine to shut down completely. You may install a trap door on a fuel tank to keep safe your fuels.

Equipment needed to clean a fuel tank on a boat

  • An electric siphon pump (or a transfer pump).
  • of gloves
  • Protective glasses
  • Mask.
  • Of cans of sufficient capacity to recover fuel and cleaning water.
  • Alcohol or detergent to clean tank.
  • A high-pressure cleaner (Karcher).
  • A raclette.
  • Absorbent tissues.
  • A waterproof endoscopic camera (optional).

How to clean a fuel tank on a boat

Prepare your work area

Before starting to clean a fuel tank, it is imperative to prepare the work area well. Working on a fuel tank means that noxious fumes can accumulate at dangerous levels. While diesel is not flammable, you still need to take the necessary precautions to avoid risks. Three critical measures are needed:

  • The boat must be out of the water in the ideal
  • The work area must be well ventilated.
  • No ignition source should be near when cleaning the tank.

If you are working on a gas tank, double your vigilance because the risk of fire and explosion is higher.

Empty the tank

If your tank is equipped with a purge valve or an access hatch (inspection hatch), then it will be easier to empty it. Of course, not all boats are equipped with these handy accessories and will have to do with!

If you do not have a purge valve or inspection hatch, then the easiest way is to remove the dipstick so that you can introduce the siphon pump to pump the fuel into the waste containers.

Clean the fuel tank

First case: your tank is equipped with an access hatch

The existence of a trap door on the tank makes cleaning much more comfortable. Open the hatch, remove the muddy deposits at the bottom of the tank. Then use a high-pressure cleaner to clean the sides of the tank. Vacuum the cleaning water with the siphon pump. Put alcohol or concentrated detergent diluted with water in the tank and wait a few hours before vacuuming again using the pump. Rinse thoroughly with water until the soapy water disappears and allows the tank to dry. While cleaning your boat fuel tank you should save fuel in motorboating if necessary. 

Second case: your tank is not equipped with an access hatch

In the absence of a trap door, it is more convenient to disassemble the tank. From the gauge mounting hole, insert absorbent cloths attached to the end of a flexible metal rod and try to eliminate as many deposits as possible. Of course, the operation takes a lot of time and you must provide a sufficient amount of rags.

An endoscopic camera will allow you to see the inside of the tank and more effectively eliminate deposits. Moreover, this gadget is inexpensive, since the price of an entry-level model does not exceed 10 euros. Once the rags come back a bit clean, you can move on to the next step.

Fill the tank with alcohol or detergent diluted with water and leave on for a few hours. Vacuum the cleaning water and use a Karcher equipped with a nozzle suitable for cleaning the high-pressure tank. Vacuum the cleaning water again and repeat the operation until the tank is perfectly clean. To finish, let the tank dry and put it back in place.

To protect the injection system, the fuel hoses must also be cleaned and the fuel filter must be replaced!

Tips to keep your tank clean and protect your engine!

  • To reduce the risk of condensation, remember to refill your fuel tank before wintering and whenever you return from an outing or when using your boat. It would be best if it is always full when you are not using the boat.
  • If your boat does not have one, install a trapdoor so that you can regularly check the condition of your tank.
  • Install a settling filter between the tank and the fuel filter to protect the injection system if the water is present in the tank.
  • Add an antibacterial additive, suitable for your engine, each time you refuel to prevent the formation of micro-organisms in the tank.

And have you ever had to clean a fuel tank? How did you do? Tell me in the comments! 

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