Lorance Fuel Flow

E

Edward Thieme

New member
I have a Lorance GPS and have a Lorance Fuel Flow unit in the NEMA 2000 network. The reason I went with Lorance was because it is suppose to work down to 0.6 gph and I use about 1gph at 6mph.

I have had two of them, the first worked for one day the second for 4 days. After that they indicate 0 gph and every now and then go up to around 0.8 then back to 0. If my boat is rocked fuel flow is shown but then back to 0.

I have a Racor Filter/Water Seperator less than one foot away before the fuel flow unit! Does anyone have any experience with the Lorance unit.

Since I am on a long trip it is a problem to send a unit in, have it returned to home and then have my sister mail it to me.

Are there other fuel flow units that are reliable down to 1 gph?

Ed on "Rambler"
 
I had the Racor/lowrance combination and it worked flawlessly. I do remember some discussions re: installation where it was very important that the sensor itself had to be oriented so as to not allow it to retain trapped air. I installed mine downstream of the Racor, above the Racor and below the engine fuel intake point.

Hope this helps

Don
 
Edward Thieme":20v3nrfk said:
I have a Lorance GPS and have a Lorance Fuel Flow unit in the NEMA 2000 network. The reason I went with Lorance was because it is suppose to work down to 0.6 gph and I use about 1gph at 6mph.

I have had two of them, the first worked for one day the second for 4 days. After that they indicate 0 gph and every now and then go up to around 0.8 then back to 0. If my boat is rocked fuel flow is shown but then back to 0.

I have a Racor Filter/Water Seperator less than one foot away before the fuel flow unit! Does anyone have any experience with the Lorance unit.

Since I am on a long trip it is a problem to send a unit in, have it returned to home and then have my sister mail it to me.

Are there other fuel flow units that are reliable down to 1 gph?

Ed on "Rambler"
Click to expand...

What a coincidence. Today I started my fuel usage testing on my CD22. I have the Suzuki 115. I finally got the NEMA 2000 network working with the Suzuki/Lowrance digital display and the Suzuki engine and Lowrance NEMA2000 GPS. I am now suppose to be reading actual fuel flow by the engine rather than an external flow sensor. I am in the process of calibrating the gauge. Today I just did test run to see how accurate is "out of the box". I installed an additional fuel selector valve so I can switch between the main fuel tanks and a separate one gallon tank. I made two one gal test runs. The first was at 1500 rpm. My gps speed at 1500rpm was 5.5 mph. The Lowrance guage I would go 9 miles. My actual gps distance traveled was 7.2 miles. My next one gal run was at 3350 rpm. Lowrance gauge showed 4.2 miles/gal. Actual distance traveled was 3.9 miles. I was hoping that that default calibration would have been closer. My next chore is to zero everything, fill the main fuel tanks and run out at least 25 gal. Then do the calibrate thing.

Roger
 
I have the predecessor to the Lowrance flowmeter, the Navman 3200. One can blame Sneaks for this. I'll list the BS I went through to get it to work, courtesy of me.

First, I installed the flowmeter just before the Racor filter, pointing up. That little sucker is nothing but a turbine with a magnet counting the turbine fins as they pass by. So I figured that pointing it vertically would make for minimum stiction and let air go right on by. Worked so far, except the fittings on the inlet and outlet were smooth, so I had to double clamp the fuel hose and crank the clamps down tight. At least it's on the suction and not on the pressure side.

The unit reads down to 0.1 Gallons/Hr, at which point the reading jumps between 0.0 and 0.3. Good enough for me.

Now the only hard part was to get it to read Gallons/Mile. Obviously this needed a GPS input, so I connected a GPS via the NMEA0183 port. I'll skip the details, except to say the flowmeter input was a single ended signal. Only one in the whole boat. However the MPG was wrong. Finally I changed the 0183 output sentence (and I assume that 2000 is similar,) outputting only one word that had mileage and speed. The reading MPG reading finally started working. So look at what the GPS is outputting. Too much data and the flowmeter gets confused.

Boris
 
journey on":199t7e8n said:
I have the predecessor to the Lowrance flowmeter, the Navman 3200. One can blame Sneaks for this. I'll list the BS I went through to get it to work, courtesy of me.
Boris
Click to expand...

LOL! The biggest problem is that Boris is an engineer and gets caught up in the fine points of theory. I was a mere technician so my tendency is to ignore the fine points, plug it in and if it works, go for it.

I successfully used both the Raymarine GPS/display and the Lowrance fuel flow sensor to read fuel flow on the Raymarine plotter AND the Lowrance fuel flow meter using the Raymarine version of NMEA 2000 (Raytalk?). I also used the Lowrance NMEA2000 bus with the Lowrance puck using the Lowrance display meter.

In fact, I even successfully tested the Lowrance GPS puck hooked up to the Raymarine plotter in lieu of the Raymarine puck and the plotter worked well. (excellent backup puck)

How long it would work? Dunno. Didn't care, since it worked almost flawlessly. Yes there was a small "glitch". When using the Raymarine GPS puck, the Lowrance meter would flash indicating no position info being received. Funny thing though, the position always tracked with the Raymarine position and every other feature worked as if it were receiving proper info. No biggie, AFAIC.



Don
 
I would like to install the Lowrance flowmeter on the 22 I am buying. It is set up with twin Honda 40s. Has anyone done this? Details & gotchas?

Thanks,
Warren
 
I have been using the lowrance and Navman for a number of years, and no problems. But I don't interface the GPs--for me it is only important how much fuel I am buring. I can always calculate the miles per gallon. You need to have the transducer, pointed up, and past the racor, not in front of the racor (or any filter--I have actually used some fine mesh filters in some applications. Currently I have 4 of the units running on my various boats. However, below one gallon an hour, I tend not to trust them. As said, they are just turbines, and are probably not linlear at the lowest speeds. My units have been fairly close out of the box, but I usually do a full fuel fill up for the calibration.
 
Thanks for all the replies. I have the Lorance fuel flow unit installed after the Racor filter and the arrow is pointed up. I am using it with the Lorance LMS520C display. I can't see anything to change so I have no idea what to do. The fact that the units worked for a very short time seems to indicate they are installed right. I guess it is a case of bad luck!

If my boat is rocked by a wake fuel flow is shown for a short time!

Ed on "Rambler" at Beufort, SC now.
 
Edward Thieme":22atq7o9 said:
If my boat is rocked by a wake fuel flow is shown for a short time!

Ed on "Rambler" at Beufort, SC now.
Click to expand...

Sounds like you may have some air in the system. Is there a way to bleed the top of it?

Or a loose connection somewhere..... Don't we all though!! :shock: :lol:

Charlie
 
Edward Thieme":27kzyrp8 said:
Thanks for all the replies. I have the Lorance fuel flow unit installed after the Racor filter and the arrow is pointed up.
Click to expand...

The hose doesn't loop back down below the sensor on the downstream side, does it? A small amount of air in that area could cause those symptoms. Otherwise, all that's left is "a bad sensor". NOT an impossibility.

Don
 
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