Using Float Sending Units and Flop Tubes

[snoopyflys]

Does anyone have experience using float send units and flop tubes in -7 fuel tanks? Are the any issues with the flop tube interferring with the sending unit?

Thanks,

[revenson]

I bought a project that had flop tubes and capacitive senders, but I had float units and wanted to use those with conventional fuel plumbing instead.

Yes, I believe the flop tube will get in the way of the float sender. It's been a while, but I recall taking out the flop tube and capping that exit. Also had to remove part or all of the 'trap door' that is part of the inverted system, as well as removing the brace that serves as a 'guide' for the flop tube.

[Kevin Horton]

Originally Posted by snoopyflys

Does anyone have experience using float send units and flop tubes in -7 fuel tanks? Are the any issues with the flop tube interferring with the sending unit?

I built an -8, which has the same tanks as the -7. The flop tube would interfere with the float sender, if the float sender was installed on the access plate on the inboard end of the tank. My instructions said to put the float sender in the next tank bay, with the sender mounted on the rear baffle. That works OK, but there is still a small amount of fuel in the tank when the gauge hits zero.