Nice detective work Jim! Only un-fun part now is fixing it.

Since they are small have you considered goofing over them with Pro Seal?

^^^ This. You have absolutely nothing to lose by trying it.

I had a weeping rivet in the lower inboard forward corner after I had rebuilt my tank with all the SBs applied, painted and re-installed it. I cleaned the area and mixed up a 10cc syringe of sealant, then used that to fill in the rivet and put a little around the edge. I put the syringe in the deep freeze for later use -- I assume it's no longer usable but I haven't needed it again. It's been completely leak-free for about year and a half now.

Well(d)
 

I just asked a pro to weld me a tank out of 1,5mm aluminum.
Will let you know the results once I have it back.
New tank, sloshed with tankslosh, fully covered with RTV where needed. Left it loose for some eight months or so with auto gas (10% ethanol over here): 8 months no smell, just laughing at your posts. Then suddenly a leak. I turned over the tank on the other side: small leak as well. Probably eaten by ethanol? Who knows. Anyway: I'm fed up with it. The design is OK, the new tank is about that size.

I visited a fellow builder today and looked over his work in progress. He has a factory built tank. It certainly has a lot less external goop than mine, but then again: mine hasn't leaked in 5 years!

Tony - I'm going to remove tank for 100% inspection and repair.

Quick side note... I'm now flying the D-180 Dual Display I bought from you back in November. Flew right seat several times and lovin' it. My 12 has two EFIS, 496, and mini iPad running ForeFlight. Four color displays - feels like I'm flying a biz jet.

Jim

Glad to hear life is good in Ohio! I've had my tank out and apart a couple times for the SB work as well.

Not a big deal. Yeah, I liked the dual display setup too. Will probably put in a second SV one of these days.