I have had a 16' round Intex above ground pool for a few years and have spent a lot of time and frustration keeping the inflatable ring inflated. This has caused multiple instances of thousands of gallons of water flooding my yard when the ring got too low on air. It also caused my skimmer to regularly suck air when the ring go too low and the mounting bracket didn't stay in place. I've tried many tips mentioned on this forum and elsewhere for finding and fixing leaks with some success, but recently I found what I consider to be the 2-part fix to end all fixing, and it was also cheaper and easier than everything else I have tried or read about. I am posting it here so it will be easy for others to find:
This is a 2 part idea to solve 2 time consuming issues with the ring, so let me list them separately. If you don't have large leaks or sunburned ring, skip to part 2.
PART1: Fix large leaks in the ring that don't stay patched in the sun. I had a large (1/2" slit) leak in the ring that patched fine with the vinyl path kit until the sun came out, at which point the patch got gooey and leaked. I found that if you patch it in the evening when it is cool, and then spray the patched area with white rubber leak seal spray:
Rust-Oleum 267970 12-Ounce Leak Seal Flexible Rubber Sealant, White
Rust-Oleum 265494 12-Ounce Leak Seal Flexible Rubber Sealant, Black - Flex Seal - Amazon.com
it keeps the patch cool and prevents it from leaking. It also provides another layer of sealing in case there is a small leak in the patched area. This can also seal small leaks on the top if you can't find exactly where they are, but if you do part 2 of this solution, you won't care about small leaks.
I also highly recommend spraying this on any sunburned areas of the ring. I live in the Mojave desert, so we have intense sun that turned the ring black on the top. This is where the 1/2" crack formed. Spraying the burnt area with the white rubber sealant prevents it from getting further damaged and seals any small leaks. You do need to mask a bit around it to leave a clean line if you care how it looks. Also shield the water with cardboard to prevent overspray getting in the water. The skimmer can handle any little bit that still gets on the surface. There is a brush on leak seal, but it doesn't come in white, so it would seal leaks, but wouldn't work to keep a patch cool for large holes.
PART 2: Fixing small leaks WITHOUT HAVING TO FIND AND FIX THE LEAKS!!!!!! (This is the one that I think will save many people a ton of work)
Don't waste time with soap, saran wrap, stethescopes, or even making your pool look white trash with PVC pipes and noodles propping up the ring, or even doing surgery to insert objects inside the ring to keep it boyant. Here is the only fix you will ever need:
1) 1 rubber stopper #3 size with 1 hole ($2 if you can find just one at a local hardware store, otherwise $10 for many at amazon)
GSC International RS-S-1H-2H-1LB Stoppers Rubber, Assorted Solid, 1, and 2 Hole, 1 lb., Pack of 38: Amazon.com: Industrial Scientific
2) any aquarium air pump and some tubing (~$10)
Amazon.com : Tetra 77851 Whisper Air Pump, 10-Gallon : Aquarium Air Pumps : Pet Supplies
Amazon.com : PENN PLAX Standard Airline Tubing Air Pump Accessories, 25-Feet : Aquarium Air Pump Accessories : Pet Supplies
3) a right angle drip tubing flag connector to connect the tubing to the rubber stopper ($2)
Amazon.com : Raindrip 122010A 10-Count 2 GPH Flag Drippers : Hose Drip Systems : Patio, Lawn Garden
Now just remove the plug from the ring and replace it with the rubber stopper. Then insert the flag dripper into the stopper and connect the tubing so that it hangs straight down and runs to the air pump. Just leave the pump running 24/7 and let it keep the ring perfectly inflated without fixing your leaks! It costs about $0.005 per day to operate, and the pump has such low pressure that it will never overinflate the ring. It will just fill it up until it is full and keep it there as long as it is plugged in. Some larger pumps may be too strong, in which case you may want to add a tee and drip valve to allow some to escape, but the small pump I had lying around worked perfectly without anything like that. There are also adjustable pumps that would allow you to dial in the firmness of your ring, but that is probably overkill. Also, you might want to replace most of the aquarium tubing with drip tubing to prevent it from rotting in the sun, but you will want to use a drip connector to transition back to the softer tubing for connection to the pump. I also loosely covered the air pump in some aluminum foil to keep it from getting damaged in the sun, since it is outside near the pool. I already have power running to my filter and chlorinator, so I plugged the air pump into the same cord.
I have had this in place for a few weeks now and it has kept the ring perfectly inflated. No more fluctuation with heat either (it used to be tight in the sun and droopy at night after cooling down). The best part is, I still have small leaks that I never fixed, and I just don't care anymore! I don't even care if I get more small leaks in the future, because I already know I won't have to spend one second of my time finding it or patching it. The pool also looks and functions exactly as it did when it was new (except for the white rubber coated part from part 1 above), since the ring is still tight with air, and not saggy with random objects stuffed inside, or flopped over a bunch of pool noodles propping it up.
I hope this helps other people to never spend another minute fixing leaks in their inflatable ring! Feel free to comment if anything is not clear or you have questions on how to make this work.