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Bf225 gauges any thoughts?

Hey fellas, twin bf225's and i have the i'm guessing original gauges. First issue is they dont read the gph on any of the motors and on the small bottom screen it says off so no gph and its hard to determine the perfect spot for efficiency. How can i diagnose if its a bad gauge or no signal to gauge? Engines are 2002's. One gauge reads the rpms for both engines and thats fine but the other is the gph and nada. Can i replace them? Where can i find them? Its not a problem more like an annoying. Help please honda gurus.
 
I have a pair of '03 BF200's and my gauges don't have a gph option. I was under the impression the gph was a nmea reading that was no available on the older engines. I have a floscan on mine that work fine. There would have to be a mechanical sensor inline somewhere to send the signal to the gauge. I am not sure where Honda would put them, but my floscan sensors are after the water separators, before the primer.
 
You guys are right i'll check out all electrical connections first and will also take a pic of the gauges i have so you guys can see what i am talking about. I'm also planning on moving the fuel gauges to the front of the console. For some reason they left them inside the center console. But will see and update accordingly.
 
According to the wiring diagram I have of the digital gauges (origin unknown), the fuel pulse wire lead is colored green. So follow the green wire and check each connector on both ends of the wiring harness.
 
According to the wiring diagram I have of the digital gauges (origin unknown), the fuel pulse wire lead is colored green. So follow the green wire and check each connector on both ends of the wiring harness.
Unfortunately i dont have digital gauges i have analogs i'll snap a picture of the gauges and so you can see them. Pretty much one round gauge encloses two rpm dials. One for starboard and one for port. The other gauge is the same way just this one reads gph. Unfortunately it doesnt work but idk if they ever did. Engines are 2002's so idk if they ever had a gph option or else why would anyone put them there. Just seems odd to me. But maybe once you see them you might know more than me. I might just install new gauges and rearrange the whole thing.
 
Understand you have analog gauges. However, the engine is fuel injected and I don't think the ECM changed much until 2008 and 2010. So I suspect that it is reading fuel flow. Whether or not it is sending out the information via an ECM signal. I do not know for sure.
 
Ok so pics are here an it is a twin scan set of gauges. So i'll have to do more research on these gauges. . . Can someone inform me on these gauges? I know the gph set reset when you open the ignition and sweep up and down but after that nothing else.
 
I believe those are the newer generation. I just can't seem to find these and how they are connected and if i indeed have a sensor to measure the flow. On the gph gauge it says "off" on the digital read out on the bottom but idk how to go on about this.
 
You definitely have floscan sensors inline to operate with those gauges. I have the single gauge that you have to flip a switch to toggle between the port and stbd. I do like the twin readout though. You didn't mention what boat it is on, but if you look at your fuel lines, the sensor will be after the racor and before the primer. Mine are bolted onto brackets inside my battery compartments where the fuel filters are. You can get the installation instructions for them on the floscan site listed above, then go from there. If yours are not showing usage, it is most likely the sensors are bad. I had one that worked, but the other did not. I replaced them both. BTW, the cheapest place to get the matched pair was directly from floscan.

this should help

http://floscan.com/html/Manuals/TwinScanGPH-LPH.pdf
 
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Ok i'm back with an update... Boat is a 2002 island runner 31' with twin honda bf225's. I suspected the previous mechanic had put something under the filters and i have confirmed they are flow sensors for the floscan gauges. The sensors look to be in bad shape pittted and rotted which is why i suspect he threw them under the filters when he installed new fuel lines. This is great since all i have to do is buy a new pair of sensors and hook them up. Hopefully the gauges will read after that. If not i'll continue to troubleshoot. Definitely sensors are bad and not seeing fuel through them so. Lets see as i install newones.
 
Just call the guys at floscan or go on their site and order a matched pair. Make sure to follow the directions, no teflon tape.
 
I was under the impression that the floscan and other units which run via the fuel lines were not accurate due to the motors having an internal fuel reservoir they syphon from... ie you get a bucket load of fuel go in then the motor sips from the reservoir meaning its hard to get an accurate idea what the motors are really drinking (please correct me if I am wrong thats how it was explained to me).

If you want accurate fuel usage look at getting the digital speedometer (is quite expensive) just be careful to buy the right one... there is a new NMEA version out now and I am not sure if they will work with the old engines.

I linked up the Honda Digital speedo and kept the analog RPM gauges as they are easier to read particularly if your in a hurry. (I also sent Chawk a copy of the wiring diagram) which is mighty helpful. If you do get the honda Digital Speedometer you will also need to purchase new wiring (from memory there is 6 or 7 wires in the newer wiring Vs only 3 in the older) which should suit you considering you mention changing the speedo location.

Good luck whichever way you go.

DM
 
FYI - Honda did not adopt the NMEA standard until about 2010, so older engines will not interface with the NMEA 2000 standards.

I have had those expensive "new style" Honda digital gauges since early 2008 and I'm not terribly pleased with them. Generally, they are hard to read and flipping through the "mode" switch while underway is a PITA. However, the fuel usage data is very accurate - within +/- 3.0 gallons on a 100 gallon fill up. Consequently, the GPH calculation will also be very accurate, but the MPG estimate is only as accurate as your speed reading, which is typically not very accurate because it is based on either the internal petit tube, or an external petit tube that is installed to bypass the internal one.
 
The floscan is very accurate once calibrated. The vst holds a quart of fuel, but once it is full, every drop that is burned has to be replenished, so that fuel goes through the sensor. At idle speeds, the gauge won't show movement because the flow is very little on a 4 stroke. I have mine set to show slightly more burn than I actually use, just to be on the safe side. There are switches on the gauge that can be used to calibrate it. I can make it nearly dead on, but I am ok with where it is now. I am talking maybe a few gallons difference on an offshore fishing trip.
 
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