Fuel gauge on momentary switch?

I have a 1986 Yamaha outboard new to me. I am running through the wiring seeing what works and what doesn't.

unlike my last boat which was an I/o which had all the gauges wired into the ignition swicth, the fuel gauge on this boat is powered from the fuse block at the helm which powers lights and other accessories...there is a momentary switch that powers the fuel gauge, push it up and it powers up, release it and it shuts off.

It all appears to be original wiring and setup to the boat.

Is this a normal setup? I guess it would prevent you from leaving your gauge powered up while not on the boat and running down the battery? Its really not a problem to me as I rarely rely on the gauge anyway and I can always check the level if I want to.

Just wondering if it was something standard or some jerry rig that somebody put in.

Re: Fuel gauge on momentary switch?

Having gauges on a separate switch is absolute nonsense with one exception. In some cases, dual battery setups may use a switch to switch one gauge to read either battery. Two fuel tanks can be switched between a single gauge in the same manner. But to have the gauge on a momentary switch defies logic. All gauges, I/O or not, should be wired to the ignition switch. Nothing inherently wrong electrically with doing it that way, but if the other gauges are powered when the key is on, why would you not want the fuel gauge on as well. Another switch is just something else to go wrong.

Re: Fuel gauge on momentary switch?

Maybe it is supposed to default to a main tank and the momentary causes it to check a secondary? Or maybe the momentary bypasses the key switch, so you can check the level while the key is out, yet when it is running, it is powered off the key.