Fuel flow meter / gas gauge

[Don_P]

Regarding fuel-level probes, I noticed in the May issue of Sport Aviation that Belite has a relatively new fuel-level probe out (http://beliteaircraftstore.com/fuprsy.html) that actually has no "probe" at all, just a 1/4-inch NPT male fitting that screws into the bottom of the tank. This senses fuel head pressure and outputs 0 to 5 volts (empty to full). The "no probe" idea interests me because, for my Onex, the plans call for cutting the probe down, not because it won't fit in the tank but because it's too long to take out of the tank because of insufficient room between the bottom of the tank and the floor of the aircraft. Functionality, accuracy, and reliability are unknown, at least to me. Has anyone tried this product? One thing I'm particularly curious about: My tank vents to ram air, so the pressure in the tank will vary somewhat. James Wiebe of Belite was unable to say how this would affect the probe's output, just that it probably would. I'd appreciate hearing from anyone who knows anything more about this product.

[fastj22]

That is really promising.
Since switching to MoGas from AvGas in my plane, my capacitance fuel probe I got from Sonex (Princeton Probes) quit working properly. Others have had the same result.
I wonder if it will work with the MGL xTreme EFIS?

[radfordc]

One problem with the sight tube as designed is any sloshing in the tank creates large movements in the sight tube. The fix is to install a restrictor in the sight tube. I made a brass fitting with a 1/16" hole through it. I have my sight tube marked for both sitting still on the ground and for level flight.

[DCASonex]

Problem of avgas and mogas with capacitive sensors is difference in characteristics of the fuel. Choice of EFIS to display readings from capacitive sensors will not change this. I have used only avgas in mine but have seen reports sensor can be re calibrated for mogas.

On that sight gauge. Just removed mine. After 2+ years [plastic tube was getting very hard particularly inside the fire-sleeve, and decided it presented more hazard from fracture than it was worth. Have capcitive sensor and fuel flow meter and both work well, so sight gauge was expendable. If I loose electrical system, will be looking to land before remaining fuel becomes an issue anyhow.

David A.

[daleandee]

For the simplest, most reliable, easiest to install, works with any liquid, always accurate, lightweight, cost saving, non-electrical, indestructible, fuel reading device ... one could employ the method shown here:



For the record I have the Princeton probe with the MGL Flight -2. Works extremely well using only 100LL.

FWIW,

Dale
N319WF

[Sonex1517]

Dale - humor me as I did not sleep well.....what technique there?

[daleandee]

Dale - humor me as I did not sleep well.....what technique there?

Isn't that a slot in the panel to view the gas tank level through?

Dale
N319WF

[fastj22]

I was looking through my MGL xTreme manual tonight and noticed you can setup a virtual fuel tank. You just set the total capacity and use a fuel flow sender to keep track of the level. After you fill up, reset the gauge. I also thought of marking the tank with a sharpie at critical levels and installing a mommy mirror under the panel to view it.

The Belite sender is intriguing though. Looks like you calibrate it empty and full to get your voltage range, then calibrate your gauge using different fill levels. They say you need to recalibrate when switching between avgas and mogas because the specific gravity is different but its impervious to ethanol. recalibrating between fuels is kinda a pain. A quick google showed MoGas specific gravity is 0.739 @60F and AvGas is 0.68-0.74 @60F