K2XT, Rick here. I've recently been having trouble getting my tower to extend
easily. It is a US Tower TX472 with the motor drive. Symptom when I first
experienced the problem last fall was very sluggish starting. I'd give it a
few seconds in each direction and then it would get going.
So now that I am in the midst of extensive maintenance (new winch cables, and
some antenna work) I notice that the motor stalls out completely, and blows
it's circuit breaker or thermal cutout, whatever it is, after 2-3 seconds. And
of course there is no upward movement of the sections. I replaced the starter
capacitor. Same thing. I removed the motor and it runs fine with no load.
Ok, so my next theory is a pulley is jammed, and that's where I seek some
advice. I tried turning the "steering wheel" pulley by hand while the motor is
off. That is the approximately 8 inch pulley that is driven by the belt from
the motor. In the direction that should raise the tower sections it gets so
tight that there is no way whatsoever a human could turn it more, and my gut
feeling tells me there is also no way I should expect the motor to turn it.
So, do I have a bad pulley on the tower sections, and how to know if a pulley
is bad?
So, this morning, with the tower horizontal, I loosened the winch cable and
removed a bottom pulley. A 3.5 inch dia one. I can hold the bushing and try
to spin it. It turns and I can feel the bearings inside but trying to get it
to spin and it only goes maybe a quarter turn. The feel of the bearings is
sort of uneven. Could that bit of friction be causing the trouble? Of course
I may find another pulley (hopefully) that is completely frozen, and that would
solve my problems. Any opinions? Any first hand experience with such a
situation? I put some motor oil on the bearings, no change. What about
soaking the pulley in solvent, then oiling?
Thanks for any input.
Rick K2XT
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