[AT] Tube problem

[Steve W.]

OK here is the problem. Tube type 4.00 x 8.00 tires on a portable
generator. Split rim.
They will not hold air. I pulled them apart and inflated the tube, stuck
the entire inflated tube under water and found no leaks. Valve stem is
new and didn't leak either. I reassembled them, reinflated to 15 PSI and
put them back on. less than 1 month later they are flat again. I give up
on them. BUT does anyone have an idea?


Steve Williams
Near Cooperstown NY