Fuel tank vent B nut leaking.
 

Is there a way to tighten the fuel vent B-nut on the inside of the tank without major surgery? My right wing perpetually drips fuel out of the vent when the tank is filled to over 25 gallons.

We bought the quick build option specifically so we wouldn't have these issues. I recently had to remove the left wing tank and send it back to Vans because it was leaking like a sieve in multiple locations, and I do not want to repeat that exercise if I don't have to.

Jack & Dave,
There is no way to tighten the internal "B" nut for the tank vent without removing the access plate at the root end of the tank.
If it is any consolation you are not alone with this. I have seen three aircraft with this exact issue. All were QB kits.
Removing the tanks is not as difficult as it may seem. In a day you can have them back on. The down time is waiting for the sealant to cure.

You bet there is a thread. In the -10 forum search for vent leak. Not an uncommon problem with QB wings. If you are not yet painted I would consider removing the tank and going in from the back after getting a repair kit and Proseal from Vans. I discuss how to make it Ok to fly and stop it on the ground in a post.

Have fun!

I had the exact same problem with my QB tanks. There are some previous threads on the same topic which you may have seen. You can get limited access by removing the sender plate and adapting a spanner. There is limited clearance between the nut and the top of the tank for a normal ring spanner.

See: http://www.vansairforce.com/communit...ighlight=b-nut

Martin

Sorry, I meant a ring spanner modified to with a slot to get over the tube.

In my case tightening wouldn't have helped..the problem was a bad (cracked) flare on the line.. thread here:

http://www.vansairforce.com/communit...highlight=vent

We just cured a leak using advice from the previous threads. The tightening solved our problem but ours is not QB. What we did slightly differently was made 2 x tools using 2 x sockets with a slot and a 90 degree handle on each. By calculation we thought we could get about 20 degrees of movement on each turn through the fuel tank sender hole. As a socket has 12 points so would need 30 degrees of movement to go to the next point, we made up 2 x tools with a 15 degree offset between each tool and then alternated each tool every turn.

You are very welcome to borrow the tools but they are in the UK!

I checked mine, based on previous posts, before installing the sender unit. One was tight, the other I got a good 1/2 turn. I used a stubby wrench with an open end/closed end. I used a long piece of safety wire twisted to the closed end of the wrench and slipped the open end over the b nut, pulling on the safety wire to tighten the nut. I had a bore scope to watch what I was doing. I dont think its possible without pulling the wing and removing the sender.

We did our repair on the wing. So we removed the wing root fairing and the fuel sender only