I have an electronic fuel gauge on my 208 adventure. My gauges are Yamaha clusters. The last time I fueled my boat the gauge read about 3/4 of a tank after refueling. I refueled recently and the gauge was reading about an 1/8 of a tank. I was going to fill it up all the way when I found that I still had about a half of tank of gas. My tank holds 86 gallons. Is this typical with these gauges to be that inaccurate? Is their something I can do to tweak the gauge or float if that's the issue?