Fuel Tank Capacity???

I prefer to take the tank down, some do it with the tank in place. Before you do anything check the ground strap on the fuel line to sending unit to ensure its clean and not broke.

To remove the lock ring I take a flat blade screw driver and tap it with a hammer about an inch or two and the lock ring will come loose. Then just pull the sending unit and inspect it for dirt. Unclip the brass float and throw in in a pale of water, if it sinks thats your problem if it floats check the little electrical wiper on the sending unit to make sure its making contact all the way through its motion. my bet is on the float though