[TowerTalk] Sluggish crank-up tower

[Joe Giacobello, K2XX]

Rick, I had a similar problem with an LM-470.  It turned out that the 
solution was a rusted shaft between the motor and the large pulley.  A 
squirt of oil onto the shaft and toward the portion of the shaft inside 
the motor did the trick. YMMV.

73, Joe
K2XX

> Rick Stealey <mailto:rstealey at hotmail.com>
> Friday, June 20, 2014 12:10 PM
> 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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