The 6 port Andair fuel valve installed in my IV-P has been progressively
getting more and more difficult to turn from one tank to another.  Has
anybody got an idea on how to lubricate the valve? Any ideas on what might
be happening inside?  Before I attempt to disassemble the valve I'd like to
have an idea on what might be causing the stiffness in rotation.  Thanks in
advance.

Hal Woodruff