Why would a Wheel Rim not hold Air?
 

Took one of my 19" LR3 rims to a tire place because it lost air they inspected the tire and the Rim reset the tire on the rim and said that they could not find anything wrong and it was not leaking, took it home put it back on the car and surprise next day its lost air. Took it back and they did it all again and again said can't find any problems and showed me the wheel in the tank and no leaks, next day tire is losing air. Took it to another shop and the same thing happened, they said the rim was bad but could not identify why just said maybe if i Polished the inside of the rim and tire seat that may fix the problem. So as the 19" are worth nothing do i just junk that rim? i really can't waste anymore time taking it to tire stores and i am just about to put so Blade MT's on the 19'sand don't want to have it deflate straight away as i will not be using them much till an off road event, any thoughts anyone?

I had one that the bead area was a hot mess and some aggressive cleaning solved the issue. It would seal fine off the car but when load was added it would leak.

Thanks ArmyRover i will give it a go and see if cleaning up the rim works.

It easier to do with the tire off the rim. Deflated would work as well but it's a pain

Tire is off Rim as going to use it to fit some MT's

I would wire brush both beads/lip.
Soapy water once the tire is on to find any leaks.
Hopefully it's not cracked anywhere.

My old wheels off my Subaru had built up a layer of whatever sealer stuff the place my dad took it too for 6 plus years used as sealant. Was literally as hard as epoxy and looked like it too. When I kept popping beads it took me several careful days with a Dremel to remove that stuff. After however no issues.