Your method is really quite ingenious. I have done complete rebuild on several of these and you are right, no fun at a ll.
I am fortunate to have an ultrasonic cleaner so, once I remove a PTO from a radio, I can sonicate it to get the old grease out and then flow a lubricant in. I might not chose Tri Flow as it is pretty low in viscosity and not intended for durable use applications but I¡¯ll see what I learn next time I need to do one of these.
This would also work well with Collins PTO¡¯s.
Sonicating in white gas would be more efficient at removing the old grease, then sonicating in denatured alcohol to clean away the white gas residues (outdoors, preferably).
Some grades might be soluble in a solvent, which would be really great as the solvent would evaporate leaving a decently viscous lubricant behind.
I had one idea I have yet to try since I do not have any needy radios handy but, if one could get a small vacuum pump, one could put a hose over concentric shafts and pull solvents through the parts and then suck low viscosity lubricant in afterwards.
Gary
W0DVN
PS: For the Drake guys, this would work really well with the preselector caps in the Drake 2A and 2B receivers without even needing to remove them from the radios (a treacherous task, far worse than anything Ten Tec ever dreamed up).
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On Jan 27, 2024, at 3:16?PM, Winston Jones <jones_winston@...> wrote:
My advice is based upon past reading of a Ten-Tec thread on freeing up stuck PTOs in Ten-Tec radios.
You do not have to remove the PTO from the radio.
Sometime back, I used this technique on an old Ten-Tec Omni-D I bought with a tight PTO.
First, forget about rebuilding the PTO. Ten-Tec used to sell a rebuild kit which included new bearings, springs, grease, etc. Those have not been available for many years. Anyway, the process was a nightmare, even with the parts kit.
Here¡¯s how I fixed my PTO:
First, remove the knob and flange, per manual instructions.
Use a hypodermic needle to squirt denatured alcohol into the bearing housing on the tuning shaft. Do not use isopropyl alcohol, as it has water in it.
Rotate the shaft from end to end many times to remove the old grease.
Then spray Tri-Flow lubricant into the bearings, and again turn the shaft many times from end to end. It may quite a while, but eventually you will feel the tuning begin to loosen up.
The PTO I fixed is still working well after two years.
I¡¯ve read where many have successfully used this technique.
On Jan 27, 2024, at 2:46?PM, Jack, VA4JP/K0JP <va4jp@...> wrote:
?A new topic? I have searched through many possible sources for an answer and know it is not but I will ask in relation to my specific situation.
I recently purchased a 580 Delta that is in very nice condition, however the seller did not fully disclose an issue with the PTO. The rig functions as it should in all respects save for the hard tuning of the PTO. I have seen it described in a number of ways but I think "like pushing a marble through molasses" is the best. Rotating the shaft has a gummy feel to it and certainly causes me to suspect aging lubricant as the cause. In my search for a definitive answer I found only one mention about replacing the grease with the admonition that it CANNOT be done independent of the PTO rebuild. Is that still the consensus of Ten Tec experts?
This would be a problem for me since I know the rebuild kits have not been available for very long time plus the fact I can no longer do some of the very fine assembly work that was routine for me a lifetime ago. If the old lubricant cannot be cleaned out and replaced with fresh then I will likely have to offer the Delta for sale. That's entirely because I am primarily a CW operator and the difficult tuning, along with a tiny amount of backlash, presents problems in the CW filter bandwidth.
Does anyone have any additional wisdom for me or is "nope, can't be done without a rebuild" the final answer?
Thanks and 73,
Jack, VA4JP/K0JP
Steinbach, MB and Karlstad, MN
