fuel management gauge

[neverenoughx2]

I have a 1994 28' marlin with 1994 250 yamaha's. The fuel management gauge stopped working years ago and I just never bothered with it. It just came on the other day and just reads zero. Anyone know what motor it is reading from? I pretty sure it reads just one engine. I don't know how this gauge works and where I should start tracking it down from with out pulling everything apart and tracing the wires. I was hoping for a shortcut if someone knew where I should start looking.

 

[SkunkBoat]

Follow your fuel line(s) from the tank to the motor(s). You will find a flow sensor.

 

[DennisG01]

Is it original equipment to the boat? Although, it really doesn't matter. They're still in business so you might contact them or check their website for a manual. But they are a pretty simple, and generally reliable, piece of equipment. Even though that's an older model, I'd bet the manual is still available on their website. However, a good place to start is to remove, inspect, clean and replace every electrical connection associated with it.

 

[glacierbaze]

If you have 2 engines, and only one gauge, then you also have a toggle switch to select between the engines. The needle on the gauge reads the gallons per hour of the engine selected, and the numbers in the window are total gallons burned for both engines. Easy to see which engine is being read, if the needle is moving at all, by running one engine at a time.
That toggle switch is also used to set the total to zero when you refuel. Should be able to trace a wire from that gauge to a nearby toggle switch that you forgot what it was for.
Somewhere, probably back near the Racor, you will have 1 or 2 fuel transducers in the fuel lines. If it was set up to read each engine, it will be in the fuel line to each engine. If it was only set up to read totals, the transducer will most likely be in the fuel line between the tank and the filter. Not good, because the transducer reads a tiny turbine's rpms, and unfiltered fuel can jam it up.
Yours is the older Cruisemaster series, 5500 if I remember correctly.