Fuel Gauge

[Jean Marc]

Does anyone know how the fuel gauge operates on the control panel of an Ericson 30+ with a 5416 Universal engine.
When removing the panel there is no connection from the fuel gauge to the tank. when looking at the gauge and what seems to be the place where the tank sensor is it would seem that the connection would be a small tube about 1/8" and not an electrical connection.

 

[Alan]

This won't help you, but I found the old fuel gauge for my 1978 E30-2 in my bilge last week while troubleshooting a fuel tank leak. I was not aware that my boat ever had a gauge. I also found several sections of old brittle thin hose similar to what you describe. My leak occurs only when I fill the tank all the way, so I filled it and found that fuel was shooting out of a piece of that small hose that is still attached to something on the top of my tank, presumably a fuel level sender unit mounting plate. I think that you can possibly anticipate the development of such a leak in the future when your hose gets brittle and breaks.
I believe that sending units are normally have electric sensors, not a pressure sensor like I apparently have fitted to my tank. This does not amuse me - I can only hope that I can somehow access the hose fitting on the tank without unreasonable effort - such as removing the engine and tank. I will either plug the hole or install a different sending unit (only if I am lucky enough to have the standard sending unit bolt pattern on top of the tank and can do so without removing the tank, which has only about 2 or 3 inches of clearance below the cockpit sole). I could cut a hole in the cockpit sole over the sending unit location and put an access plate there - but since I have my wheel mounted on the sole, I'm hesitant to weaken the sole in this area.
If I find out anything useful about the sending unit or its mounting, I'll let you know. The broken gauge seems to have been made by Marcra? Mfg in Costa Mesa, which doesn't exist anymore as far as I can tell.

 

[Jean Marc]

Thanks
Looks like we have the same setup. Indeed I observed a leek as well when my tank was full. I also need to find a way to block the hole until I can find a solution. Ideally would be to find a replacement gauge since I would prefer not to change the sender unit, although it is accessable.
I will let you know if I find something.

 

[jreddington]

I've never seen a set up like that.

I'm just guessing based on your description but it sounds like your tank sensor works like the level sensor in a washing machine. As the level comes up the fuel (or water in a washing machine) compresses the air in the tube. The gauge senses this pressure and moves the needle, kind of like a barometer. And like a barometer, it is sensing very small changes in pressure, inches of water column, so might go bad with age.

Best thing would be to replace the hose to the gauge and hope it works. Note that to properly sense, the tube needs to go all the way to the bottom of the tank to work. However, the connection you see to connect the tube might have a "dip tube" that goes near the bottome of the tank to make it sense properly. If not, then you'll have to track down an replacement unit or retrofit an electric float level type system. Any vent systems on the tank must also be operating properly or the resulting pressure or vacuum in the tank will cause false readings.