sending unit with flop tube

[N15TP]

I want to install a flop tube on my flying rv-4 and I'm not sure what my options are with the sending unit. The one I have in there now will be in the way with the flop tube. Is it easier to get a remote sending unit or try and build a header tank.
Thanks,
Josh

[Dean Pichon]

I have flop tubes in both tanks and mounted the senders in the rear tank baffle in one of the outboard bays. You will need to pull the tank no matter what you do, so where you put the sender will not be much of an impact. As I recall, the -4 plans show the recommended sender installation location for a tank with a flop tube.

Unless you are planning to do negative G aerobatics, flop tube(s) may not be necessary. Do you have an inverted oil system?

Good luck,

Dean

[N15TP]

I am installing a christen oil system and a rotec TBI also. I have the tank off is there a diagram out there? I didnt see it in the plans

[greghughespdx]

Not sure about RV-4 plans, but it's drawing 16A in the RV-7/RV-8 plans. I just did this mod on my left tank last month. A few photos from my RV-8 tanks here.

The sending unit is moved and installed in the next outboard bay. Cut a hole in the rear baffle to mount the fuel sending unit. I used a tank repair kit to mount the sending unit in, then installed the repair disc in the rear baffle. The hole in the root rib where the sending unit used to go is sealed up with a blank aluminum disc.