Multi Function Gauge 34200-96L2

[ekraus50]

2003 World Cat.
2 - 2019 DF140's
2 - Multi Function Gauge 34200-96L2
2 - 75 Gallon tanks one for each engine.
Total fuel onboard 150 Gallon.
I am disgusted with these gauges.
I will start with when the gauges were installed a Suzuki Factory Tech assisted with the setup.
I was one of the first to use these gauges in the US
Port gauge both fuel senders are connected to it all connections are per Suzuki.
Problem 03/16/21
Port Gauge reads 60 GAL Fuel Used
Starboard Gauge reads 0 GAL Fuel Used
Port Gauge should show Total Fuel Used for all outboard motors installed.
So I put 63 Gallons in the Port tank and 50 Gallons in the Starboard tank.
Thats 103 Gallons not 60.
Port gauge shows trip 154 Miles as well as GPS.
Port Gauge shows Average Fuel Economy 2.5 MPG.
But based on the GPS and actual fuel used 1.49 MPG
Thats pretty crappy !
My Honda 130's averaged 2.3 MPG + my WOT speed was 2 MPH higher.
So not only am I disappointed with the motors but the gauges suck.
The only useful info on the gauges is the RPM (if its correct) and the analog fuel display.

[Moonlighter]

You must have something markedly wrong with both the gauge and engine setup to have those issues.

The gauges have proven incredibly close to 100% accurate and reliable since they were introduced throughout the rest of the world in 2015. Your issues therefore point to an incorrect installation and/or setup, which is a worry, because they are really so simple that its hard to stuff them up. But if you use the wrong harness or dont complete the fuel setup procedure correctly, you are going to have problems.

You would be best to take it to an experienced Suzuki dealer who has done the required technical course on these gauges and has also done numerous installs and has the e perience in real world to get it sorted. I doubt very much whether this is something we can diagnose remotely, and Im not going to try.

Regarding the engine fuel economy, the DF140A are one of the most economical engines available from any manufacturer.

But, they have to be set up correctly, starting with engine height being right, and then they need to be propped correctly. I cannot see any way they would be worse than the Honda 130’s IF THEY ARE SET UP CORRECTLY.

Start with engine height. I bet they are currently buried too deep.

Due to Suzuki’s offset drive shaft, they run a very different gear ratio to other manufacturers, so you cant run the same prop as you would fir example on the Hondas and expect it to be right - it wont even be close. The most common prop used on both DF140’s and 115’s would be a Suzuki 3 x 14” x 20” stainless.... but that will of course depend on the boat and whether the engines are a good match in the first place for that size and weight of boat. You need to prop them to reach at least 6000rpm at WOT. There is a sticky thread near the top of this forum that explains engine heights and propping for our Suzuki engines.