Small Engine Troubleshooting Problems? Ask a Mechanic Now.
You should not fill the tank above the red line in the fill neck, to allow for expansion of the fuel.
But over filling should not cause a leak.
If fuel is leaking, it is most likely due to a bad/missing seal in the gas cap, or a stuck float needle in the carburetor.
Make sure the carb drain screw has not come loose.
Also, that tube you pushed up in to the generator case needs to be brought back out the hole. It is an overflow drain, and is designed to let the gas flow out of the case in the situation of a problem, rather than allowing the gas to build up in the case, which creates a fire/explosion hazard.
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