Bit the bullet converting tanks now
I figured why wait for this problem to come to me in the middle of boating season - so our 1968 38 Aft Cabin is in the middle of it's conversion to aluminum tanks right now. The project is going well but it is not one for the faint of heart. This may be the one time it's easier to work on an aft cabin configuration. The old tanks came out and the new tanks went in through the doors, but man is it tight. I never put ethanol into my old tanks, so I can't address the questions about what things look like after the ethanol starts to dissolve them. The guy next to me in the storage barn, has a later model 40 foot Hatt and is having all kinds of problems with what he says looks likes "leaves" in his fuel. He is plugging up filters at the rate of 1 every couple of hours. He is not, however seeing the black varnish effect that we've all been reading about. Maybe that all comes later. He does seem to be somewhat in denial about how big a problem this could be, and I don't have the heart to give him the chapter and verse from BoatUS, though I suggested he might want to check into it.
I had been a proponent of the polyethylene tanks at first, but going with aluminum does allow you to get exactly the tank configuration you want. In spite of a pretty nice array of polyethylene tank configurations available, it's unlikely that your going to find one with the fill, vent, and pickup right where you want them. This will add to the frustration and cost of putting in replacement tanks. I have to admit that the lack of baffles in the tanks was somewhat of a concern, but it might not have been a showstopper in a smaller tank. The Aluminum tanks were built and shipped from Speedy-Tanks 5 days after I faxed them a drawing, and they really are a thing of beauty. Thanks to Unique Name for the recommendation. By the way, I have 2 perfectly good 150 gallon tanks. If anyone is interested, they can have them gratis.
I have been taking a lot of photos of this operation and will compile them for everyone to see when the project is finished.
Eric