How not to install a poly tank

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Jul 19, 2008
Think some of you might be interested in seeing this problem. My 78 FJ 40 always seemed to have a interior gas smell, and I assumed it was just the usual cheap poly tank problem commonly complained about by others on this forum.

Recently, I decided to just get an OEM tank and fix the problem. With taking things apart I discovered the PO had removed the fuel separator, closed all the openings and left no vent for the tank. The poly tank appeared to be venting though the sending unit gasket which was in terrible condition. Some of the screw holes had been stripped and new ones drilled, and the opening was badly warped. Here are the photos:
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My new OEM tank is now installed and I'm trying to decide how to vent the tank. There is the easy pinhole method and the fix it OEM-style. The Smog pump is replaced with the PS pump and the charcoal canister just sits there disconnected, so an OEM is not very reasonable. I've seen some other really cool looking homemade fuel separators, but I dont' really understand how to go about making one.
Would it be any benefit to get a fuel separator and connect it to the charcoal canister? What would be the better option?
get the fuel vapor separator, and run it to the charcoal canister. why people remove them is beyond me.

having a functional evap system on the tank reduces if not eliminates gas vapor smell, but also increases gas mileage. gasoline has a natural vapor pressure which causes it to evaporate, faster when warm. why not introduce these vapors to the intake tract on the carb, and burn them instead of venting them to atmoshpere?
Agree with the above. Vapor recovery system is one of the few stock things on my Pig.
When I desmogged I left the evaporative emissions intact for this very reason. In fact, when I went to TBI EFI, I still used the system.
Thanks. I would like to get a fuel separator, but they do not appear to be a very popular item. SOR out of stock and cruiser does not appear to have them. Any ideas on where to get one?

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