Completed Initial Leak Test of The Left Tank
 

Initial test of the left fuel tank has passed.

The Float access plate was tested with the cork gasket installed. Now that the initial test was a success, I'll pull the plate, remove the cork gasket, pro seal up the plate, reinstall and retest.

The multimeter is measuring ambient temperature for a reference as I recorded pressures during the test.

During the test I used a leak test fluid to check all the seams and rivets.

I'm keeping my fingers crossed for you. I'll be right behind you, I'll probably get to that in a couple of weeks.

Lots of luck! My RV8 tanks are being tested now also. So far, so good....

I will keep my fingers crossed for you too, that the cork gasket wont turn to goo like mine did.

Van's and Synergy recommend eliminating the cork gasket and just using sealer now.

Second Tank Passed
 

Completed my initial leak check on my second tank today...Passed.

Tomorrow I'll seal up the end plates, let them cure for a couple of days and then do a final leak check on the tanks.


Using leak detection fluid to track down any leaks.

Great news!

Did Van's post anything publicly to that effect? I'm getting close to closing my tanks up and am still going back and forth on "cork + Permatex" vs "cork + Proseal" vs. just Proseal.

When i took the factory tour, the guy there told me to toss the cork gasket as far as i could!!

For The Historical Record
 

I realized that I never really finished this thread.

So after both tanks passing the initial leak test I removed the cork gaskets and installed the plates with just pro seal.

After letting the tanks cure for at least two weeks, I retested using the same procedure. Both tanks passed the leak tests.

Procedure used for testing tanks:

1. Closed or sealed up all tank openings
   
2. Installed a 0 to 15 inches of water pressure gauge on the tank drain fitting.
   
3. Set up a temp probe next to the tank.
   
4. Pressured up tank to 9 inches of water.
   
5. Recorded the pressure and temperature every 30 minutes to an hour for over 12 hours.
   
6. Used leak test fluid periodically to look for leaks. (SNOOP or equivalent)
   
7. Let sit overnight, continued recording temp and pressure for another 12 hrs.
   
8. Ended test

The pressure / temp recording allowed me to track the pressure movements (and they will move) during the 24 hr test. The method for making sense of the pressure fluctuations is:

Pressure fall and temp falls = normal contraction of air volume.
Pressure rises and temp rises = normal expansion of air volume.
Pressure falls and temp stays the same or rises = possible leak
Pressure stays the same and temps rise = possible leak
Pressure increases and the temp falls = laws of physics ceased working ;)

meh. something something dark matter something handwave.

Maybe a dumb question, but what cork gasket are you referring to?

I ask, because I happened to install my fuel senders in my RV-10 wings over the weekend. The senders that came from Van's with the wings had a black rubber gasket.

The -7 kit came with a cork gasket to seal the float mechanism plate. I't was suggested by Van's and Synergy Air that not using the gasket was a viable option. Apparently some of the cork gaskets would fail over time.

I got rid of those rubber gaskets and just used the tank sealant. Worked fine on both tanks.

I actually ended up using the cork gasket, but coated with Permatex "Aviation Form-a-gasket" including around each screw:



No leaks through the gasket, however both tanks still leak through the capacitive plate BNC connectors. Haven't figured out how to solve that one yet.

I got rid of the whole access plate, and never cut the hole in the first place (but I have the capacitive sensors Van's used to sell...never a bit of an issue with them, knock on wood).

It can't leak if there's no hole there in the first place :)

Shop leak testing is a good thing, but realize the real test comes when you G 'em up with 120 lbs of gas in 'em.

Can't wait!