Beneteau 40 fuel level sensor

[William Dill]

My fuel gauge shows that my tank is full when I know that it is not. The electronic gauge shows that I it is monitoring tank #2 when I only have 1 fuel tank. The marina "guru" claims that I may have to get to a half a tank before the gauge will start to accurately reflect the fuel level. It seems to me that this is based on a premise that it works correctly. Does anyone else have this problem and have they been able to correct it?

[Rafa]

Hi William,

Mine works like yours, and when the gauge shows half, the tank is almost empty. But never tried to correct the problem.

Saludos.

[Mike Brown]

Part of the problem is with the shape of the tank not the guage. The tank is not square on the bottom but beveled to match the shape of the hull. The gauge is located in a deeper part of the tank and thinks there's more fuel than actually is. Not a problem when the tank is full but once you get to less than half it can become an issue. I keep track of engine hours as well as how much fuel I take on.

Mike

[Bruce Bogdanoff]

I have a B-40, hull 182. My gauge reads tank 2 and when full it reads 3/4, sometimes one bar above 3/4. When it is empty it will read 1/4. Since I know the limitation of the fuel gauge, I use it in an advisory compactly,

[David]

Hi B40 2007

There have been previous posts on this issue.

I had the same problems

a) Tank 2 - Fuel wire is on wrong pin behind VDO panel – see previously posed wiring diagram - I changed this to Tank 1.

 

b) My boat also had the wrong VDO fuel sender and arm - (arm was short and straight)- Beneteau provided the correct sender with bent arm to reach top of tank (top of tank is above top of sender).- Beneteau drawing of this was previously posted.

If sender arm is catching at top of tank, I would guess sender arm is bend is too much as it should not catch.

 

c) To overcome irregular shape tank I installed a NMEA2000 programmable tank level adaptor (calibrated it with 5 points by filling - EMPTY, ¼, 1/2, 3/4, FULL)

I connected VDO sender to my C80 via adaptors, the NMEA2000 tank level adaptor and a SeatalkNG backbone.

 

The C80 now displays both an analog gauge and digital volume of fuel remaining.  It seems reasonably accurately.  But there are some compatibility issues with Seatalk2 Seatalk1 and SeatalkNG.  It would be simpler with an E80 or C wide screen. 

I no longer use the VDO fuel level display in saloon.  It now only shows water and volts.

I may sometime add engine data to the C80 but that requires senders and an analog to digital engine data adaptor.

 

Regards David