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Has anyone tried to convert a portable fuel tank to a permanent one?
[/font]Andrew,
I have not done this but I suppose it could be accomplished safely. It may depend on just how the portable tank is configured. Personally I would NOT want a quick connect at the tank (in a permanent setting) so if the tank already has a quick connect built into the hose connection/tank fitting, that tank may not be a good candidate. I'd prefer a simple threaded to barbed (for the hose) fitting.
As to the fill side of the equation, that may take some custom engineering. A portable tank will have the venting built into the fill cap, a permanent tank usually has a dedicated vent. If I was going about a conversion, I'd cut away the molded threads for the present fill cap. Cut them flush with the top of the tank, leaving just a flush opening. Then I would design a two piece plate used to cap that opening and to attach a fill hose. One piece would be a backer ring with a tapped bolt circle pattern. This would be slipped into the inside of the tank and the outer plate would be attached to it, effectively sandwiching the tank top between them.
Prior to assembly, the upper plate would need both a vent fitting and a stub length tube welded to it to attach a fill hose. Probably 1.5 or 2.0 diameter for the fill hose, which would be mated to a purchased cap assembly.
As I said, I've not done this, just brainstorming in my head as I write this. If you decide you want to proceed, I'd be happy to discuss my thoughts with you more in depth.