DF140 fuel flow meter

[silvertriton]

Hi, I have just bought a boat with pair of 2003 DF140, I am buying a Garmin GPSMAP 740s and I would like to have the fuel flow information like MPG or GPH in addition to speed, what is the best way to do so? I have heard that Suzukis prior to 2005 had some NMEA connection problems, if so should I install instead a Garmin GFS10 meter but since this is 200$ per engine I want to be sure the cheaper NMEA connection is not an option first...

[Harper]

I think (not absolutely sure) that 2004 was the first year for NMEA 2000 compatibility.

One thing that I would caution you on, though. The GFS10 will be inserted in the fuel line to the motor, which will cause you some problems on the DF140, or any other of the midsize or V-6 Suzuki outboards. What happens is this: the fuel flow in the fuel line pulses off and on with the cycling of the low pressure fuel pump. This cause the reading that you get from the GFS10 to fluctuate between zero and somewhere between 25-40 GPH. It does this constantly, as the low pressure pump cycles off/on (or more correctly as the float valve opens and closes, stopping and starting the fuel flow to the VST).

So you consequently will not get a reliable fuel flow reading from the GFS10 or any other sensor that is installed in the fuel line going to the motor. It is my understanding, however, that you will get a fairly accurate picture of total fuel used over time. The Floscan meter has the same problem with motors with dual (high/low pressure) fuel pumps, and state in their literature that their meters will not work on most Suzuki four strokes (along with other brands that use the dual pump setup). It is also my understanding that Faria has a flow meter in which the user can adjust the sampling interval of the fuel flow, and thus overcome the off/on cycling of such outboards.

I'm sorry to be the bearer of bad news. I have the Garmin GPSMAP 546s, which reads the SMIS data from my '07 DF150. But the GFS10 sensor would not work on mine, either.

[Moonlighter]

Some people have had success with connecting Suzukis as early as 2002 to a NMEA2000 network.

No guarantees! But.....

If you try it you will need

1 x Suzuki engine interface cable per engine
1 x Suzuki reverse K8 adapter cable per engine, this is the cable that connects the new interface cable to the older round plug on the pre-2008 Suzuki 4 strokes.
1x NMEA 2000 starter kit.

Next, it is likely that the software in the new interface cables will not be fully compatible with the pre-2012 engine year Suzukis. It will give you crazy fuel flow and fuel used data. Other data should be fine, though.

To get around that, you will need to overwrite the current software on the interface cables with the older version 2.30 software. I believe that Brownspoint Suzuki marine may be able to do that for you if you purchase the cables from them, and you will also need to ask them to configure both of the interfaces to suit your model, hp, and model year engines.

Or, if you have access to a Lowrance HDS unit that you can temporarily attach to your network, it is easy to copy the software onto a SD card and do this yourself. I can send you the version 2.30 software.

As i said, it will be possible that this will all work, but I cannot and do not state that it will. 50/50 or maybe a bit better chance, in my estimation. Browns Point may be able to give you more information on the likelihood of it all working if you call or email them. They have more experience with this stuff than most other Suzuki dealers.

[silvertriton]

Many thanks, I have just got the boat yesterday and have not had the chance to see in detail what is under the hood....the owner said that he has an SMIS dial which works but the fuel flow system he had installed failed and probably the fuel flow connector needs replacing....I will check this out and keep you posted of the outcome

[Moonlighter]

If the boat already has a SMIS gauge installed, then it must also have a NMEA 2000 network of some kind installed, because the SMIS gauge will only work on such a network. It wont work at all otherwise!

I suggest you wait and see what you actually have when you get it. Note: both the network and the engine must be turned on (not necessarily running, but key turned on) in order for engine data to appear on the gauge.

If there is an SMIS gauge installed, and it shows any engine data such as rpm, temp etc then it would mean that there is already engine interface/s installed. In which case, fuel flow data will also be available. Just have to set up the pages to show it.

By the way, this is what an SMIS gauge looks like, just in case there's any confusion:

Suzuki Outboard 990C0-88161 4 in. Multi-Function Gauge - Browns Point Marine Service, LLC

They are essentially a Lowrance LMF 400 (or 200 if 2"), but with slightly customized software for Suzuki.

[silvertriton]

Hi, Thanks, yes there is an LMF 400, the previous owner said that something was shorting the system but not sure what...I will have a better look in a couple of days..