Need help with tank leak

[Larry DeCamp]

I have read many threads about proseal and sucking in loctite. I did not build the tanks but did test them for over six months full of gas with no leaks. I did attempt to get the tank off including assuring the bolts on the Z's were removed, No Joy. Apparently the skins are locked to the spare flange in the dimples beyond relief. I feel I would need to destroy the tank to remove it.

The leak appears to be in the rear bulkhead because the stains are along the tank skin parting line with the bottom wing skin. I assume that flight stress over 80 hours or thermal expansion stress has initiated this small effluent.

I know sloshing is not historically prudent. Any suggestions would be appreciated before I order a tank kit or new wings.

[Jesse]

It will come off. They can be really hard to get off sometimes. Push up and down. We've even had to tap on the fill cap flange with a block of wood and a rubber mallet before.

Of course, double check that every single fastener is removed.

[rv7charlie]

You can *carefully* lift the skin & carefully wedge something thin, like popsicle sticks, under the top flange to release the dimples. Be sure to support the tank and/or have help, to prevent dropping the tank quicker than expected.

Charlie

[rvbuilder2002]

There are 3 bolts for every rib in the tank. It is easy to accidentally miss some.
If you haven't removed that many bolts, you will damage the tank if you start using force to try and remove it.

[f14av8r]

Even with all the screws removed, those dimples keep a fierce hold on the tank! Getting the tank off is MUCH easier if you put a piece of plastic between ALL the countersink / dimpled screw holes. I use cheap For Sale signs from Home Depot. They are just stiff enough to allow you to work them between the skins but thin enough that they don't bend anything. Us as many pieces (signs) as needed to get pieces of plastic between all the screw holes on the top and bottom. Then, once you have all the other mounting hardware loose, the tank will pull off easily.

[David Paule]

Originally Posted by rvbuilder2002

There are 3 bolts for every rib in the tank. It is easy to accidentally miss some....

I believe that on an RV-3B there are only 2 bolts per Z-bracket. At least that's what drawing 7 says and that's what I put on mine.

Dave
RV-3B, now on the fuselage.

[rvbuilder2002]

Originally Posted by David Paule

I believe that on an RV-3B there are only 2 bolts per Z-bracket. At least that's what drawing 7 says and that's what I put on mine.

Dave
RV-3B, now on the fuselage.

Oops
There are not a lot of the new wing RV-3's.... and I didn't look at his signature so assumed it was a 7 or 8

[Plummit]

Originally Posted by rvbuilder2002

Oops
There are not a lot of the new wing RV-3's.... and I didn't look at his signature so assumed it was a 7 or 8

That's OK Scott, I for one appreciate the feedback you provide. Not to hijack this thread, but I may have ot pull the tanks on my QB -10. Does the 3 per rib hold true there too?

thanks
-Marc

[rvbuilder2002]

Originally Posted by Plummit

That's OK Scott, I for one appreciate the feedback you provide. Not to hijack this thread, but I may have ot pull the tanks on my QB -10. Does the 3 per rib hold true there too?

thanks
-Marc

Yes, it does.