310 aux tank feed problems

[Topper]

I finally have my wife to the point she will do long enough legs that I need the aux tanks. I have the 31.5 gallon aux tanks and the poh says to fly 90 min on the main and then switch to allow room for the return fuel to not overfill the mains. Seems about correct on the right side, about the time the aux tank is nearing empty, the main is back to full. The left tank is not working correctly, it takes forever and seems to be pulling from the main and the aux at the same time. The main level never goes up and I couldn't get the last 15 gallons or so to feed at all, I think it always pulled from the main. Guessing we need the fuel valve rebuilt/replaced. Anyone else ever experience this?

Thanks,

Jim

 

[Jim Carpenter]

It does sound like a fuel selector valve problem, but it could also be the in-line aux tank pump malfunctioning