Ok so boat is still new to me and on about 1/16 fuel gauge reading i try to put in 100gal.
Full to the top at 89gal....!?
My friend has a 2006 382 and the has a simular issue with tank not taking much fuel vs. gauge.
Are these tanks smaller than adveritsed or do we really have 50gal reserves?

1/16 on trailer or in water? Mine reads wildly different on trailer vs in water. On top of that once the needle starts bouncing off full, I tend to start looking for a gas stop.

Thats so funny. I never even paid the fuel gauge much attention until I installed this.....


https://youtu.be/gGZP1ALe6T8 Now it moves as much as the tach does !

As a reference, the sender in my 311 was somewhere around 15.5 inches and the tank is around 19 inches deep. Level on the trailer it could read empty, but have still have quite a bit of fuel. Definitely not 50 gallons though.

1/16 in the water at rest.

My fastech is empty when the gauge shows quarter tank . Found out the hard way and never let it go below half . Jeff wurl

my new to me 312 fastech im still learning as well. i know i went on a 70 mile poker run and ran her pretty hard with a full tank. came back showed still above half. was very shocked. went back out yesterday with it showing between 1/2 and 3/4 made it about a mile dropped to 1/4 yellow light came on, got to the island knowing i had a fuel dock nearby if needed. fuel gauge showing back up above 1/2. decided to play it safe and put $100 in for the ride home. fuel gauge now reading full again. not sure what to think at this point.

lol...Yes mine does the same....Like Jeff, as soon as gauge get's to half I put fuel in... Better safe than sorry.

Chris

On mine there are two screws to adjust to calibrate the fuel sender. So when it is full of fuel I adjusted so it would read full on guage and then when nearly empty I adjusted the - screw so it reads Empty. If that doesn't work keep track how far you ran and figure you got 1mpg for twins and normally when you go to fill up again you will be within 10 gallons of how many miles you think you ran.

Once while trying to get rid of old gas and run it low, I ran out. The gauge was at 1/8 and the engines shut off about 60 yds from the ramp. That was close. I plan to fix that cause I don't like to show fuel if there is none.