Picked up a couple used corny kegs about a month ago along with an oring kit. After replacing the orings, I fillled them with about 20psi of compressed air and drizzled some soapy water around the mating surfaces on the lid, poppet valves and posts. Looks like one of the kegs has a slight leak at the base of the poppet valve housing. Any way to seal these up better? Teflon tape? Oring?