Fuel Level Sensors

[timfwalsh01]

Folks,

I actually did a search for Resistive Fuel Level Sensors, calibration procedures and found little.

Per Pages 7-50 through 7-52, I understand that you must make ten (10) level pours of equal volume for both tanks.

Can you calibrate 1 gallon X 10, or does it have to be the full tank?

Do you calibrate each tank only once?  Taking fuel out of the tanks was not fun!!

Thanks  Tim

 

[dynonsupport]

To calibrate fuel level sensors requires approximately 10 pours - quantify of each pour varies depending on the fuel tank volume. Fuel tanks aren't linear, so SkyView cannot "guess" what the resistances (or voltage, for other sensor types) will be for mid-range... and of course, we assume that you want ACCURATE fuel level indications.

Generally, fuel level calibrations (performed correctly) only need to be done once. However, if after the calibration is done, no backup is saved, if a unit fails, after the repair we often have to deliver the bad news to customers that since no record / backup was retained after the fuel level calibration, it must be re-done.

So, if you don't want to repeat your fuel level calibrations... Insert a USB flash drive, then SETUP MENU > SYSTEM SOFTWARE > EXPORT SETTINGS. Put that USB flash drive in a safe place.

Folks,

I actually did a search for Resistive Fuel Level Sensors, calibration procedures and found little.

Per Pages 7-50 through 7-52, I understand that you must make ten (10) level pours of equal volume for both tanks.

Can you calibrate 1 gallon X 10, or does it have to be the full tank?

Do you calibrate each tank only once?  Taking fuel out of the tanks was not fun!!

Thanks  Tim

 

[Carl_Froehlich]

Tim,

A couple of additional thoughts:
- Level the plane. Most require a jack under each wing to get to level flight attitude.
- Use the fuel tank calibration as a way to flush your fuel system. Do the tank calibration and fill up the tank all the way (at some point the fuel probe will top out - that will tell you at what level the fuel probe will start to read accurately). For most people a two gallon at a time pour is about right. Pump all the fuel out via your electric fuel pump connecting a hose to the firewall side of the fuel line. Send the return fuel through a standard auto fuel filter and collect in 5 gal cans (that way you can reuse the fuel as you know it is clean). When the pump runs dry, turn it off and then measure the residual fuel remaining in the tank by draining via the sump valve. This will tell you usable fuel.
- Repeat for the other fuel tank.
- Disassemble and clean the aircraft fuel filter. If it has stuff in it, repeat the fuel system flush until the filter is clean after the flush.
- Finish the calibration and pour 5-10 gallons in each tank and note the SkyView fuel reading. If accurate you are done. If not try again.

Keep a fire extinguisher handy as you are messing with fuel.

Carl

 

[timfwalsh01]

Carl,

I recently installed a new fuel vent system.  The plane is currently devoid of fuel.  The hole for the Fuel Level Sensors will be drilled out next week.  It will be another two weeks before I put fuel back in.  Thanks for the tips - most helpful.

Dynon - I will make sure that I save the setting!!  Thanks  Tim