Under reading fuel guages

[apatti]

If they were indeed accurate at one time, the bend in the float must be OK. I'd look for something common between the tanks since it would be unusal for the both of them to fail/change the same way.

Is there a grounding problem? You could disconnect the gauges from the senders and place different value resistors across the input and see what readings you get. This will let you know if the gauges are OK. Though, I suspect they are.

[Trevor Davis]

I am the builder that Tony is refering to
The gauges read ok until about two months ago when first the one and then the other started undereading. Neither of them now venture more than a bit over half when tanks are full. the one drops well below the "E" mark (off the clock) when current removed while the other drops slightly below the "E". The strange thing is that the measurement movement still seems to coincide with fuel used. It is almost as tho the rheostat in the tank has "shifted" its position. I'm going to check the earths as a starting point thereafter hook up another set of gauges and compare the readings. Any other suggestions will be most welcome
Trevor Davis
Rv-6 now builing an RV-7