Well I spotted a bit on algae growth in the glass bowl of the Racors on Tagit the other day so decided that even though I treat my fuel I wasn't comfortable going into the season with the possibility of bug in the tanks. I also had one tank (my reserve tank) with fuel over 12 months old in it, and I hated to think how buggy that might be if it had got infected as well.
FORTUNATELY, I recently met another forum member Fishermen (Neil) who has just started a part time business polishing dirty diesel. He bought a very sexy machine to polish 10,000l of extremely dirty fuel on his own new (ex-commercial) boat and then sailed across from Aussie using the fuel he cleaned. That was a good enough reference for me, so Neil kindly made some time after work last night to come and give Tagit's fuel the treatment.
I had about 1000l in 3 tanks to clean, with just enough spare tank capacity so that we could pump fuel around the tanks without having old fuel contaminate the clean stuff. Once we had worked out the best access to the tank bottoms, the process took about 2 hours. There first cycle or two pumps the fuel through some big sucka magnets that break up the bug and other contaminents and take any water out of the fuel. Examination of the results of this stage showed no water and a small amount of contaminents. Once you have finished this cycle the fuel is then pumped again through a big filter to remove any remaining contaminents. As you are doing this you can see the pressure drop across the filter and get an idea how much gunk is being removed from your fuel.
End result last night was that Tagit's fuel was not badly contaminated, and I might have got away with just normal filter changes. Personally, I think it was worth doing just for the peace of mind, and the fact that I will definiately save myself at least one set of filters that I would have had to use to remove the bug through normal operation.
The machine works really fast and the fuel flows more or less at normal filler pump speeds. Neil, as a keen fellow fisher, is good company to talk to, and apart from smelling a bit 'dieselly' when I went home to the good lady ("you ain't getting into my bed smelling like that"), it was a very simple and painless excercise.
If you have a diesel boat and are concerned about fuel bug at all, send Neil (Fishermen) a PM and have a chat with him.