Not a member here, but happened to see this and have some experience so I thought I would share my experience. I had a 100 gallon preformed that I put in about 10 years ago, and managed to crack before I got it into the ground. I used a Beckett repair kit from Home Depot, figuring I had nothing to loose. It lasted over 5 years, and when I replaced the preformed with a flexible liner when I enlarged the pond a little bit, I gave the preformed away to be used by someone else with the repair still intact. The kits cost less than 20.00, so if your repair doesn't work long term for some reason, you might consider a kit. It was very easy to use.

Have just pulled one wheel off a log splitter the tire of which has sat flat for lord knows how long, probably through at least one winter and summer. Unfortunately we had to make the splitter roll about twenty feet, thus breaking the bead on one side. No way that I could see to reestablish the seal. Then, finding this thread I tried the ratchet trick, first putting dish detergent - maybe too much dish detergent - all around the circumference and then putting the air to it. Massive bubbles from a couple of locations, and the tire does not inflate. So I guess I will first take out the valve stem and see if the extra air will make it pop, andif that doesn's work then some silicone caulking the way someone suggested.Don't think I'll try the ether/lighter fluid trick, though. One thing I am not clear about, and that is, does prolonged application of air result in a seal, like well over 5 minutes? I have a pretty good Campbell-Hausfeld compressor that should provide enough. maybe I should try that again

Best to go head and get four brand new tires installed. Check out firestone they are always running specials like 4 tires for under 100 bones, you could spend that much messing around trying to get the leaks fixed in the ones you have. I have seen older tires that actually leak thru the sidewall of the tire itself. I had to buy one for a manlift just the other day ($305.00 worth hopefully your is a bit more normal tire) it was leaking thru the sidewall of the tire itself and could not be repaired. The manlift is a situation were the tire sets alot outside and I guess they eventually dry rot a bit.

You just answered my first question. I thought they looked like they were aluminum clad. The miters show the material being thinner than any vinyl product. Finding a leak in a multiple mulled unit is very troublesome at times. The leak can be coming in at a higher level and working it's way down. The best way to try and dial in on the area it's leaking from is water testing. Get out the old garden hose and ladder. I would also remove that trim board on the inside below the triple unit. Take the garden hose and start on one of the outside triple units. Set your nozzle on stream and spray the window straight on. Hit each corner and then along the brick. Do this for around two minutes or until you see a leak forming. Do this with all three windows and don't spray above them yet. If a leak occurs while spraying then you'll know where to look. You can try and track it down by looking in the cavity you pulled the trim off. Just use the process of elimination to spray the window down and hopefully you'll find it. Then let me know what you find.