Hints and Tips



Cleaning the Fuel Tank

Anders Flodin tackles the job on his Sun Odyssey 51


After 20 years it was time, and inspired by another article here, I got the stuff together to make my own Diesel polishing device. I have owned the boat for 5 years and never refueled, tank is 400-500 Liters. I bought a big filter (the white thing in the pic.) and an Algae-X magnetic thingy. If this works is a different debate but I got it used together with the filter from Ebay and they sell it for big bucks at the Volvo-Penta site so I thought that if Volvo recommends it, there might be some truth to its value, or not…. I bought a pump new, gear-type pump with a pre-filter in the shape of a screen. Assembled it all on a piece of wood for portability. Getting the fuel meter out was the hardest part, I used a lever about 1.5 meters to get the lid up….

Set-up, I used a plastic pipe that I taped the diesel hose to so that I could point it in different directions in the tank. The return went directly back to the tank through available ports for heaters, generator or whatever extra equipment you have that requires diesel.


I got so much dirt from tank….this came after 5 seconds

The pre-filter for the pump clogged with this slime within 20 seconds. I cleaned the filter 4 times in 5 minutes. I was surprised to see the amount of sludge that was growing down there. I had used anti diesel bacteria substances but that was not doing the job apparently. I am very happy that I did this job, that dirt could have clogged the filters in no time leaving me inoperable on the sea with family. Next Idea is to have a separate “clean” tank that can be “valved” in if there is a problem in the future. A 5L tank would do the job just for emergency and small enough to make sure there is no dirt in the diesel while fixing the filters from the main tank in an emergency.


Jeanneau Sun Odyssey 51 - Anders Flodin