Sticky pots on vintage Futaba TX?

[brian027 0]

Hi everyone -- I've been lurking for some time but need some input!  I picked up a vintage Futaba Magnum Jr. transmitter recently, and it's in good shape except the trigger and steering pots are sticky.  Looking more closely it seems to be a residue on the shaft that causes it to bind.  I've seen this on a couple TX's before but am not sure why some transmitters are affected and others not... 

In any case, are there any tips to loosen them up?  I've had some success with a touch of teflon oil and gently working them back and forth, but I'm wondering if there's a better way...?

thanks!

[sosidge 624]

I'd probably use a contact cleaner rather than the teflon oil, just in case the teflon oil affects the electrical contacts (I don't know what teflon's properties are for conductivity)

Normally that sticky stiff is grease that has gone solid over time, the pots probably came with a small amount of grease in them from the factory and that has unsurprisingly dried up after a couple of decades. Flushing it out is the right thing to do.

[brian027 0]

yeah, that makes sense.  i used the oil as it was all l i had at the time and i'd found it was good for loosening old stuck grease in other applications.  Fortunately it doesn't appear to have had any negative effects after about a 6 months and that TX is still working great (it would have been a lost cause otherwise due to other problems also) . 

before that i tried disassembling the pot by prying open the tabs on the back but that didn't help with access to the stuck shaft.    

would be interested to know what others do for any other repair efforts on these old TX's to keep them going. 

I have plenty of 2.4 GHz also but still very much prefer the old gear with my vintage cars! 

cheers 

[Willy iine 18805]

I always use WD40 as electronic contact , tool,  bearing cleaner.   It works well and does not affect electronic performance beside make them cleaner.  

I use it to clean not only contacts, I also use it to clean audio jacks.. like guitar cords that make a scratchy noise when you rotate the plug in the guitar or amp jack.  So I'd give that a try in very small amount.   Even if you accidentally get more than you want on the electroncis, unless you dunk it usually no ill effects.  

It's possible the prior owner accidentally spilled drink on the radio.  In this case a blast or two of MAF cleaner or motor spray inside directly on the electronics works well.  It can affect plastics and paint so keep it away from that.  GL with your cleaning.