fuel sending units/Shadin totalizers

[Guy Paris]

...337 G, I feel my guages are some what accurate. I check them frequently with my Shadin. I don't normally fill the tanks however periodically I do top them off. The last time 50 hours between top offs and the Shadin was within .5 gallons per hour. In other words I had not toped it off for 50 hours, when I did, the fuel on board was 40 gals. I added 84 gals. to top it off, that came out to 124 gals. telling me that I had an additional 26 gals. on board. In 50 hours of flying and fuel added to 80 gals. or so as needed during the 50 hour period, could that 26 gals. be fuel that is returned to the tanks which comes out to approx. .25 gals. per hour per engine? Guy, old72driver....