Erratic Fuel Gage…
Last summer I recalibrated my D-180 fuel gage because readings no longer agreed with the Moeller fuel gage in the top of the tank. As levels in the tank approached ½-¼ the D-180 would show an addition 2-3 gallons. After recalibrating I thought things were going well until a week ago, when at the beginning of flight, the D-180 showed zero when there was 8 gallons in the tank. By chance, I reached behind the seat back to see if the electrical connection to the fuel sender was loose. The connector was tight but when I put pressure against it the D-180 fuel gage began reading upscale.
I checked the screw which holds the ring terminal to the fuel tank sender and it was tight. I removed the screw to examine the connection surfaces and they looked clean. I used electrical contact cleaner and lubricant on all the surfaces and reassembled. Works perfect now with total agreement with the mechanical Moeller gage.
So, what caused this problem? There are times in early spring when weather conditions allow moisture to condense on everything in the hanger. I have seen water dripping of the bottom of the wings and the hanger floor so slippery you’d think you were walking on ice. I suspect that moisture caused surface corrosion on the electrical contact surfaces.
Hinckley, Ohio (1OA2)
PPL/ASEL 1970 - Sport Pilot since 2007
80 hrs Flying Aeronca Chief 11AC N86203
1130 hrs Flying 46 Piper J-3 Cub N6841H
RV-12 E-LSA #120058 AWC July 2012 N633CM
RV-12 Bought Flying Oct 2015 with 48TT - Hobbs now 459
LSRM-A Certificate 2016
Special Thanks... EJ Trucks - Crew Chief A-4 Skyhawk
MJ Stricker (Father & CFI) - 1st Lt. Captain B-17H