My 580 SuperE has a air leak at the stem?

Hi All

I'm very new to this "heavy equipment thing" I just bought a 82 580 super e to work around my house. Well so far I have some issues, new one today is my rear tire has a lot of air coming out around the valve stem @ the rim? are these tires tubless or tubed?

Thanks in advance.

 

I did not find the right solution from the internet
References : http://www.heavyequipmentforums.com/threads/my-580-supere-has-a-air-leak...

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