Picked up a 1965 220F today at a second-hand store for $12.50, very clean with a decent ventilator and original globe. Got it home and started checking it out, removed the plunger assembly when I discovered it wouldn't pump up, and discovered that the air stem was missing from the check valve......strange. I had an air stem from my 220J (1976) that I've been repainting, but when I attempted to install it, I found that the air stem female threads on the 220F check valve are much larger than the male threaded end 220J air stem. I'll obviously need to order a new check valve and air stem assembly from the store here, but just curious if the older lanterns had larger air stems? The pump that came with the lantern fits the 220J stem just right, so I'm guessing that the previous owner broke the old stem off and just abandoned ship, or something similar. Am I on the right track?