Some gas tanks load from the servo compartment and others have a hatch right above the gas tank that would be held on by a screw. In either situation, you should be able to pull out the gas tank. There made to be taken out. You're supposed to check the gas tank before every season just to make sure the rubber stopper didn't deteriorate and that it didn't loosen itself. If the tank came put together with all the fuel lines and everything installed, and you're not sure how to take it apart, ask and someone will help, but they're pretty easy to figure out.

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