Fuel guage : how accurate are they

[Bigbri]

I have an 05. 2520. How much fuel do you is in my tank with one bar left on the guage?
I feel that there is more than what is reading

 

[Brent]

I am not sure on our 2320. Several factors come into play: the boat bow angle pushing fuel to the tank aft end where the pickups are located and the length of fuel pickup tubes - tube does not go to the bottom of tank and some gas will remain when you are out of gas which could be accessed if tubes were longer. I thought if the tank was clean or new, the pickup tube could be longer providing you have an external gas and water filter like in my case, a Racor 2 micron with a clear bowl to see water and debris. Sorry this does not answere your question. We use 15 gallons at one bar but it is a best guess

 

[Megabyte]

I never relied on the analog fuel gage as they are notoriously inaccurate.

A digital fuel gage that reads gallons per hour can be programmed to read GPH, store the amount of fuel used (which also gives you the fuel remaining), and you can even set an alarm at a pre-set that you decide to alert you that it is time to refuel.

The newer Yamaha gages have the ability to do this, or there are stand alone systems that can do it.
Knowing your fuel burn in GPH allows you to calculate range as well as assisting in the fine tuning of your boat (tab angle, prop, engine height, etc).

 

[shawnee83]

On my 06 2120 with 100 gal tank, my best guess at 1 bar is between 15 and 20 gallons remain. With 2 bars I’m in the 30+ range. As mentioned, Boat gauges are not very accurate at certain levels especially. The best way to get a handle on how much is in yours at 1 bar is to fill the boat up several times when you are at 1 bar and subtract how much you put in from the total capacity of your tank. I say several times as it will give you an average and put you closer the the accurate figure you are looking for. As Magabyte mentioned, being able to calculate fuel burn and subtract it from what’s in your tank is the best way to go. I like to maintain a 20 to 30 gallon reserve and I will usually just put in the amount of fuel I think I need for the weekend or whatever based on what I’m doing so that when done, I’m left with at least 20 or 30 gallons in the tank. I’m not supper accurate with it but the point is that I don’t want a full tank all the time and old fuel sitting around. Plus no need to run with all the extra weight if you don’t need it. Everybody’s situation is different with getting fuel though and I’m in a situation where it’s easy to get where I boat.

 

[mheltunen]

A fuel gauge’s accuracy varies significantly depending on the shape and geometry of the fuel tank. The sensor/float simply rides up and down and sends the corresponding reading to the gauge. The tank on my vessel (2320 w/148 gallons) is about 14” tall. The sides are 3-1/2” strait down from the top then they angle in towards the bottom. So when the guage is reading 1/2 tank the truth is it’s actually far less. When I purchased my vessel the tank read 3/8 full. I pumped the old fuel out of the tank and it totaled 40 gallons.

Sent from my iPhone using Tapatalk

 

[shawnee83]

A fuel gauge’s accuracy varies significantly depending on the shape and geometry of the fuel tank. The sensor/float simply rides up and down and sends the corresponding reading to the gauge. The tank on my vessel (2320 w/148 gallons) is about 14” tall. The sides are 3-1/2” strait down from the top then they angle in towards the bottom. So when the guage is reading 1/2 tank the truth is it’s actually far less. When I purchased my vessel the tank read 3/8 full. I pumped the old fuel out of the tank and it totaled 40 gallons.

Sent from my iPhone using Tapatalk

Excellent explanation

 

[Bigbri]

Very good info.
Thanks guys.