Question about fuel sender replacement RV9a

[Mdragon]

I have a small leak coming from the right wing fuel tank sender. Looks like the original builder put in the sender and used the rubber gasket rather than proseal and no gasket. I plan on fixing it by removing the sender while the tank is still in place.

My question is about the screws that hold the sender in. When replacing the screws with the new sender, how are the screws themselves made from leaking? Are they prosealed as well? Do you apply proseal to the holes or screws themselves, then screw in? Or does the ring of sealant place around the flange of the sender somehow take care of this on it's own? I will not have access to seal from inside the tank.

I've researched this some and haven't found a definitive answer and want to do this job the right way, once.

 

[PilotjohnS]

I prosealed my screws in. Also I used allen screws to make them easier to remove without stripping. I figure it I every had to remove them, they were going to be tough with the proseal.

 

[Biggiesauls]

When I built my tanks a couple years ago I used proseal as a gasket for both the plate and under the head of each screw. I also used Allen head-screws as they are easier to remove rather than Phillips head screws.

With just over 45 hours of flight time on my RV-9A, no tank leaks. However the left sending unit sticks in the top position most of the time. My Dynon HDX does a great job of calculating fuel use/remaining so I’m not to anxious to replace the left sending unit…. On a tank that doesn’t leak!

There may be some pics of the tank build on my build page.

 

[PilotjohnS]

When I built my tanks a couple years ago I used proseal as a gasket for both the plate and under the head of each screw. I also used Allen head-screws as they are easier to remove rather than Phillips head screws.

With just over 45 hours of flight time on my RV-9A, no tank leaks. However the left sending unit sticks in the top position most of the time. My Dynon HDX does a great job of calculating fuel use/remaining so I’m not to anxious to replace the left sending unit…. On a tank that doesn’t leak!

There may be some pics of the tank build on my build page.

Sorry to hear yours are sticking. Never heard that happening before, but good to know it can happen. I will have to keep that in the back of my mind. My fuel totalizer is never accurate since I seem to fill to different levels ever time. Next tanks I build, I will add a tab so I get more consistent fills.

 

[mburch]

My fuel totalizer is never accurate since I seem to fill to different levels ever time.

Your avionics have a button that will allow you to enter the exact amount of fuel you just put in. Commercial fuel pumps are pretty accurate; don't throw away the receipt!

 

[PilotjohnS]

Your avionics have a button that will allow you to enter the exact amount of fuel you just put in. Commercial fuel pumps are pretty accurate; don't throw away the receipt!

I have just been resetting to 36 gal (full qty) Maybe I should try this method.
But then I will have to calibrate my fuel flow meter more accurately,,,

 

[Biggiesauls]

Your avionics have a button that will allow you to enter the exact amount of fuel you just put in. Commercial fuel pumps are pretty accurate; don't throw away the receipt!

+1 on what Matt said. regardless of quantity added I always manually add that amount to the fuel on board quantity in the Dynon. Side note…. When I fuel up I always simply "top off" so the fuel totalizer gets reset to max 36 gallons. Fuel burn always seems to be with 2/10th of a gallon of what I then top back off to.