[TowerTalk] US Tower making clinking noise

[Kenneth Sobel]

my us tower hdx-572mdpl is 19 years old.
now it makes a continuous clinking noise when it is raised or lowered.
The noise comes from either the flywheel or the flywheel shaft or the gear box.
I cannot determine exactly where.
It sounds like high frequency as the shaft rotates. Not a grinding noise.
otherwise the tower raises and lowers without any problem.
The motor, motor shaft sheave, and belt are new.
Is this something serious?
de Ken W3JJ