Interactio Optio Fuel, easy installation and accurate fuel flow

Ben Stein

Ben Stein

Publisher of Panbo.com, passionate marine electronics enthusiast, completed the Great Loop in 2017.

11 Responses

  1. Ben Stein Ben Stein says:

    David Burton from Interactio got in touch with me and clarified a little about the economy optimizer’s operation that might clarify some of the results I saw.

    David said, “The optimizer is continually learning and needs 6 values in each “bucket” in order to average an economy recommendation (to compensate for variances and changes) so even though you have run for several hours, at some flow rates it may still not be reporting accurate values since it may not have 6 values which is min to perform the calculation.”

    While I think this makes sense it seems like the app might need an indicator that the optimizer is still learning. Otherwise users may well conclude (as I did) that the optimizer isn’t accurate before it’s had a chance to learn enough to make good recommendations. I’ll continue to watch the results of the optimizer and see if it gets more accurate. At this point I’ve run over 100 gallons of fuel through the Optio Fuel and spend about 30 hours on the water with it so I’m thinking it should be getting close to having enough data at nearly all the ranges I tend to run the boat.

  2. Jan-C. Ebert says:

    Interesting little tool! I´m still searching for an affordable but NMEA2000 compatible fuel flow system for my twin John Deere 6068 equipped Trawler.
    I miss an alternative Windows program to access the InterActio system via BlueTooth. If the company decides to alter it´s product or worst case fails, users are not able to step up with the Apple/Google operating systems evolution getting an unusable piece of expensive hardware.

  3. Ben Ellison Ben Ellison says:

    I’m not aware of any fuel management systems that attempt to improve their fuel efficiency estimations with running experience. But wouldn’t the learning challenge be much easier with access to other boat data like engine RPM and Speed through the Water (STW)? Which makes me wonder of Optio’s NMEA 2000 will be bi-directional and if they hope to use such data in their calculations?

    Also, measuring low flows is really hard in real-time (especially if it’s the differential between large diesel in and out flows). I remember well when I complained about the jumpy flow I was seeing at low speeds with a Maretron FFM100 system on Gizmo’s 450hp Volvo Penta, and Rich Gauer suggested that I go to the galley sink and try to take an entire hour to fill a one gallon jug. Which is why learning fuel efficiency over real boat time is an admirable endeavor.

    • Quitsa Quitsa says:

      Isn’t that why the fuel rate displays driven by data from the engine ECM are inherently more accurate especially at lower flow rates? My experience over 12 years of electronically controlled engines, which was with Volvo D series common rail Diesels and now with Cummins QSB engines is that the fuel rate data from the ECM is accurate within 2%. That’s based on comparing the measured total fuel consumption with how much fuel it takes to fill up the tanks many, many times. The displayed fuel rate readings at idle and along the rpm curve up to WOT are also generally consistent with the manufacturer’s published fuel rate curves.

      It would be somewhat of a pointless expense to add something like the Optio on a boat that has electronically controlled engines that can display real-time fuel rate data. That would make for an interesting comparison, however. I wonder if Optio itself has ever done that.

      • Ben Ellison Ben Ellison says:

        Hi Quitsa, my sense is that engine-measured fuel burn has varied in quality over the years. It’s hard to find out exactly how it’s being done, and when I researched the issue years ago I got the impression that at least some engines are only guesstimating. The technology could be much better now.

        This summer I will hopefully check this hypothesis thanks to a Yacht Devices Engine Gateway YDES-04

        https://www.yachtd.com/products/j1708_gateway.html

        It can read the fuel flow coming out of my 20-year-old Volvo Penta — which I’d only seen before when a VP tech with a special tool was on board — and bridge it to NMEA 2000. If it is as accurate as the Maretron FFM system I already have, it would certainly be a much less expensive and easier-to-install choice.

      • Ben Stein Ben Stein says:

        Quitsa,

        Though I haven’t done the comparison on a diesel engine I’ve done just that with my Yamaha 150 hp outboard and found Interactio’s numbers to be (somewhat surprisingly) more accurate than the fuel calculations done by the ECU and Yamaha display. The Yamaha display overstates consumption by at about 10%. On the other hand I’ve found the Optio to be within 1-2% of the total as measured by the same gas pump.

        -Ben S.

        • Anonymous says:

          Interesting. Is the 10% differential visible in the current rate readings across the rpm range or just what you determine comparing totals when you fill up the tank? My guess is that the a modern Diesel with common rail is likely to give more accurate fuel rate readings from the ECM than a fuel injected outboard without the complications of spark timing and other factors that affect a gasoline engine. But perhaps Ben will find out when he installs the Yacht Devices gateway in the summer.

        • Quitsa Quitsa says:

          Interesting. Is the 10% differential visible in the current rate readings across the rpm range or just what you determine comparing totals when you fill up the tank? My guess is that the a modern Diesel with common rail is likely to give more accurate fuel rate readings from the ECM than a fuel injected outboard without the complications of spark timing and other factors that affect a gasoline engine. But perhaps Ben will find out when he installs the Yacht Devices gateway in the summer.

          • Ben Stein Ben Stein says:

            Real time readings have a tendency to vary quite a bit between the Yamaha display and the Optio’s. Yamaha is counting injector pulses and deriving a number from that, so the Yamaha readings tend to be quite consistent. The Optio is watching how much fuel travels from the tank to the engine. Because there’s an electric fuel pump in the engine that is providing fuel to the high pressure pump that feeds the injectors there can be a disconnect between how much fuel is being burned right now and how much is being drawn into the engine.

            For instance, when you advance the throttle the Yamaha display immediately shows more fuel burn, but on the Optio there’s a delay because that immediate demand for more fuel is met within the engine. But then the electric fuel pump is activated and for several seconds after that the Optio shows more fuel than the Yamaha display. My understanding is that this is the electric fuel pump replenishing the fuel drawn out of the engine. Then, after a few seconds the readings stabilize and come a little below what the Yamaha display is showing. Though periodically they will drop way below the Yamaha display or spike way above. I believe this is because the electric pump may meet the fuel demand by running for a period, then shutting off, then running again. Meanwhile, all the Yamaha display is doing is counting injector pulses and reporting on the math it has done.

            Also, bear in mind that Ben’s engine, like my own 2002 era Volvo-Penta D12s, is not a common rail engine. So, there’s not a fuel rail being charged the same way there is with a common rail, so it’s likely that his engine will behave differently than a fully modern common rail engine. I would expect there’s a good chance the common rail engine would behave closer to what I’ve described with my outboard, but I’m kind of guessing.

            -Ben S.

  4. Quitsa Quitsa says:

    Your description of what is happening with fuel flow on the Yamaha outboard sounds 100% correct. I have one of those as well on my small boat, an F115. The fuel rate is shown on my plotter via a NMEA 2000 interface.

    At least with the common rail injection system on my Cummins QSB 6.7s, I am reasonably certain it would not exhibit the cycling phenomenon you see with the Yamaha outboard or if it does, it would have a much lower amplitude. The net measured fuel flow from the supply and return should track the ECM output very closely. I confess I have no idea what would happen with an old D-12 with electronically controlled unit injectors. Might be really accurate.

  5. David Burton says:

    Great questions and comments on here. I would add to what Ben described (very well) that Optio Fuel is measuring actual fuel flow whereas the numbers you see from most engine management systems is not measured – it a calculated value of what the engine should be burning. That calculated value does not take in to consideration boat loading, weather, tides, currents, etc. etc. so is an approximation, which is one of the main reasons I started Interactio and built Optio Fuel. Great discussion!

Join the conversation

Your email address will not be published.