Simon, I have for the first time emptied my tanks over the winter rather than filling. When I took the inspection hatch off the expected crud in the bottom which can be removed but the sides of the tank are covered in a slime. With the tanks open this seemed a good time to do a PROPER JOB!!

I too would be interested in tips on this. Last time we did it we pumped all the diesel out and then sucked out the dregs with a vacuum cleaner poked through the inspection hatch. It seemed to work but think this might have ben an unconventional approach.

Has anybody had experience of how to best clean out SS fuel tanks?