I have a 1968 911T with the original Fuchs alloy wheels. Originally they had tube tires. In 2006 I changed the tubes and tires for tubeless tires. The valve stems are the common type that thread together through the valve stem hole in the wheel. They have been fine since 2006 until recently when they started leaking around the valve stem. The wheels are clean and the valve stems appear to be in good condition.

Has anyone else had this problem and if so what is the solution?

Bob Stia