Updated - Fuel Quantity Measuring Device

[gregp]

I think I’m the 3rd person to use it in the US then.

I’m 1 of 3 partners and can’t fit my family + full fuel in the plane, so wanted a reliable method to measure actual fuel quantity in the plane independent of relying solely on the totalizer for the unmeasurable range. Still plan to leave an ample safety margin, but there’s a narrow balance between being too heavy, or eating into the 1hr fuel margin I give myself.

We did notice that after filling tanks, fuel measuring device reads several gallons HIGHER than what is shown by the gauges & totalizer after resetting at full fuel (50 gal AvGas), flying for a while and comparing. On first glance it doesn’t appear to be related to the non-measurable fuel range. Going to test some more and collect more data.

I also noticed the “new” replacement gauge we got appears to have a plastic tube (not glass). Does anyone know if Diamond started using a clear flexible plastic tube instead of glass? Or did we get a modified version? If the diameter is off that could account for the difference in measurement.

[Rich]

I also noticed the “new” replacement gauge we got appears to have a plastic tube (not glass). Does anyone know if Diamond started using a clear flexible plastic tube instead of glass? Or did we get a modified version? If the diameter is off that could account for the difference in measurement.

If the inner diameter is sufficiently small it could produce a capillary effect causing the fuel to climb up a bit in the tube.

[gregp]

Quick update, filled the tanks full (50g) and when testing the fuel level indicated with the measuring device in both left and right tanks was >25. On the left tank it even spouted out of the device. I’m convinced it’s been modified. It’s got the right part number, and the ground was reasonably level. Will test more when I have more time.

[skyseeker]

Ingram, I was quoted over 700 dollars for this part which is required airworthiness equipment.

I can cut, etch, and assemble the hoses/fittings (of the standard version shown in my AFM) for much less, but i need a reference height of one of any of the 3 gauges (Standard, Long Range, or MKII as you have) so I can size it correctly. Could you tell me the overall height of your fuel measurement device?

Or if anyone could measure their device and let me know which of the 3 you've measured since they are all different heights.

As pilots we are used to spending, but I'll fab this device on my own just for the principle of the thing.

[skyseeker]

assembled the standard tank version.
if anyone needs one, i made a small run of the aluminum plates and can assemble for you if you don't have the hoses etc.
I can also make the extended tank version but would need time to model and cut/etch it.
No 90 degree bends like OEM. Smaller hose would be better too.

[gregp]

assembled the standard tank version.
if anyone needs one, i made a small run of the aluminum plates and can assemble for you if you don't have the hoses etc.
I can also make the extended tank version but would need time to model and cut/etch it.
No 90 degree bends like OEM. Smaller hose would be better too.

Curious what the Inner Diameter is for the tube you're using. Our problem may be as simple as the wrong tube size being used, or it shrunk, or was squashed. As-is, it's not been a major problem, but as we start making longer flights, a difference of 5-10gallons is the difference between having a reserve or having an incident. Next time I'm at the plane I'm happy to take some measurements of the plate.