[Rich]

If it's water, here is a hint on how to easily see water in your fuel.

Go to a grocery store and buy a bottle of black food coloring (or some other dark color if they don't have black).

Put a couple of DROPS of the black food coloring into the gasoline. If there is no water in there, you will see the black drops sitting on the bottom of the tank, or container.

If there is water, it will be tinted black and be easy to see as the black food coloring is water based and will easily mix with the water.

It may be hard to see into your tank, but if you can get access to the fuel level sender, removing this allows you to see into the tank with a flashlight. Before removing your sender, get a gasket kit, which should include a new gasket as well as sealing washers. Use the kit when reinstalling the sender.

If should go without saying but please use the utmost caution, all fuel vapors are very VERY flammable!! Don't do any of this if you don't know what you're doing. You don't want fumes going into your bilge as any static electricity or any spark could start a big fire. Be careful.