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Floscan Issue

Discussion in 'Technical Discussion' started by bobhorn, Jul 15, 2014.

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  1. bobhorn, Jul 15, 2014
    #1
    bobhorn

    bobhorn Member

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    Installed Floscan system on two SP225 FLs. The port engine always shows slightly more fuel consumption. Did the diagnostic test and at idle the port engine flows 2.1 forward and 1.7 gph back to tank. Seems reasonable. the starboard shows 17.4 forward and 17.0 back to tank. While the delta, fuel used is 0.4 in both cases, the starboard flow seems excessive. Floscan tech support tells me to just ignore it since the delta is correct.

    Still, doesn't seem right. Anyone seen this before?

    Bob
  2. TeKeela, Jul 15, 2014
    #2
    TeKeela

    TeKeela Member

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    How difficult to switch the sensors from one side to the other to get a baseline and narrow down the issue?

    OR

    Swap the two gauges to start a troubleshooting baseline.
    Last edited: Jul 15, 2014
  3. Capt J, Jul 15, 2014
    #3
    Capt J

    Capt J Senior Member

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    Port engines always seem to use a touch more fuel, and a slightly higher load factor on almost every yacht I run. I think because they're the ones with the backwards gear attached to them. As for the flowscans, can't and aren't you supposed to adjust them?
  4. Capt Ralph, Jul 15, 2014
    #4
    Capt Ralph

    Capt Ralph Senior Member

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    usually the sensors are a match set and should not be split.
  5. TeKeela, Jul 15, 2014
    #5
    TeKeela

    TeKeela Member

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    I was referring to swapping the set from one side to the other. Once swapped if the port shows 17.4gph, and the starboard then shows 2.1gph well there you go, sensor issue.

    Even though Floscan says delta is ok, I would want to see the real numbers, those floscans are not cheap. Past experience they were close on numbers and no reason they shouldn't be in this case.
  6. bobhorn, Jul 16, 2014
    #6
    bobhorn

    bobhorn Member

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    I did swap the two gauges and the starboard readings remained the same, both forward and back flows way too high.

    Floscan tech insists that Racor filter gaskets need to coated in grease to prevent air leaks. I always just coat them with oil. I'll try the grease next time I'm on the boat but can't imagine an air leak would cause that kind of reading.

    Bob
  7. bobhorn, Mar 10, 2015
    #7
    bobhorn

    bobhorn Member

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    Twin Ford Lehman SP225s. Installed a dual Floscan system some time ago. Running diagnostics it showed that at idle the starboard engine was flowing about 17 gph forward and slightly less return. Port engine was 2 gph forward and slightly less return. The delta on both was about right. Contacted Floscan and spent some time talking to their tech support and the only answer was that since the delta flow was correct to just ignore the issue.

    I then swapped the two return flow check valves, one on the engine mounted filters and one on the injection pump, between the two engines and then the port engine showed the high flow rate. So I replaced both return check valves with new ones on the port engine but the high flow rate still exists.

    So now I'm wondering if the high flow rate is the correct one.

    Any thoughts?

    Bob
  8. YachtForums, Mar 10, 2015
    #8
    YachtForums

    YachtForums Administrator

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    Bob,

    I just merged your post (above) with this thread on the same subject started by you in July 2014. We get penalized by search engines for duplicate threads. It's always best to respond to existing threads because participating members in the thread will be notified of your latest post, thus giving you the best chance of getting a reply.

    Thanks.
  9. bobhorn, Mar 10, 2015
    #9
    bobhorn

    bobhorn Member

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    Sorry, forgot about the previous post.

    Bob
  10. Capt Ralph, Mar 10, 2015
    #10
    Capt Ralph

    Capt Ralph Senior Member

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    Thru the years and banging heads with FloScan techs, I have resolved;
    Any bend in the hose, any fitting, any change in a valve, any filter change, and any time you crack a grin or smell natural methane; the FloScan meters will read different.

    Seal up the best you can. Take notes on your base line readings. Weather if the numbers per hour are accurate or not, you have a base data to compare to. From now on, don't change the filter spec or replace any hardware without starting another base data line.
    Low HP flows will kill you. The numbers will NOT make sense. But they are repeatable and will guide you to the best mpg and most important,,, if something goes wrong.

    After alot ( alot, alot, alot ) of fuel consumption & calibrations at your cruising speed, the real numbers will come around. Again the important part is a base line and compare to it.

    Rum and patience,
    rc
  11. bobhorn, Mar 11, 2015
    #11
    bobhorn

    bobhorn Member

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    Unfortunately patience is not one of my many virtues (just kidding). I'm not yet concerned with accuracy. The issue is the widely varying flow rates at idle between the two engines, 17 gph and 2 gph. I swapped the two return flow check valves and the high flow moved with them. I replaced the two check valves with new ones from American Diesel and the high flow rate remains. So the question right now is, is 17 gph at idle correct and is the 2 gph value incorrect? Did I replace the wrong check valves?

    Swapping the return valves between the engines eliminated all other issues such as air leaks, lift pumps, flow sensors, etc. Again, the actual fuel consumption, delta between forward and return flow, is about correct for both engines.

    The Floscan tech said to ignore it since the consumption numbers are correct, but there must be an explanation.

    Time to hit the Jaeger Meister,

    Bob
  12. Capt Ralph, Mar 11, 2015
    #12
    Capt Ralph

    Capt Ralph Senior Member

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    Mine bounce from 0 to 16 gph at idle. Under idle load the close up between 2 and 12.
    Were not talking high speed computers here but the try to make a stab (poor & late) to average the display.

    If you go into diagnostic mode, you will see the real time flow of the senders. As they are bouncing around more than the display was trying to tell you. The Detroit governed rack makes it even worse.

    If you're not drawing air, confirmed with a constant vacuum on your primary filters (You have steady vacuum readings?), then you're at your best.

    Small aircraft also use this stuff. Totally unreadable on the deck. Accreate as heck in da air (under load).

    Cheap rum helps here.

    ,Ralph