One of my readers had asked me if I wanted to sell one of the sets of Yaesu Az/El rotators I had, and I said I'd clean a set up and let him know when it was ready to ship. Note the Tools of Violence to the right. Impact screwdriver, large ball-peen hammer, and a 10mm deep socket, in a 1/2" drive ratchet. Getting the screws out of these things can be a real chore!
In the process of cleaning it up and getting it ready to run on the bench, I popped off the terminal strip on the Elevation rotator, and the blank-off plate on the other half of the housing so I could look at the bearings inside and see how bad the grease was.
Annnnd...no surprise here, it had dried out, congealed, and was falling out in chunks. Soooo....time to split the case halves, and at a minimum, repack the bearings.
Yup....the grease has expired.....
See the red stuff? Rust from the bearing cages mixing with the grease. The bearing cages are notorious in the Yaesu elevation rotators for crumbling into rust. And considering how the external hardware looked:
I'm not surprised that the retainers are close to giving up the spirit. They're relatively inexpensive, or were, and come two to a package, along with the 40 bearing balls that should get replaced if you're doing a deep dive into the rotor:
I was able to get the screws on the azimuth rotor loose with just a couple of whacks with the impact screwdriver:
But I still have a couple of stuck screws on the elevation rotor after slugging away for a good hour:
And the screw heads are getting chewed up enough that the impact screwdriver can no longer find purchase on them. I'm going to slot them with a Dremel Tool, and then use the flat-blade bit in the impact screwdriver.
All this rusted out hardware will get replaced with stainless, and the Philips-drive heads replaced with socket heads.
This started out to be a "Clean Up and Check Out" project, but it's turning into a rebuild project. I'll use Mobil1 red, tacky, synthetic grease to repack the bearings, as it doesn't ooze oil everywhere in the Summer, and doesn't freeze solid in the Winter.
Have to call Yaesu Friday morning and get the parts ordered.....
This will be a very interesting project to watch. Thanks for making it a topic on the EBoG log.
ReplyDeleteIt's pretty much just mechanical stuff. I'm not "restoring" it, I'm just rebuilding it to replace the worn-out parts.
DeleteYikes! Did Yuasa decide on cheap chinesium metal for their bearings or what?
ReplyDeleteSounds like you'll be delivering a far better product once you rebuild it than Yuasa when they sold it.
They're not that bad. There are several things you can do to keep them from getting into this condition, like use a plastic trash can slid over them from the top to act as a rain shield. And they really should be regreased every five years or so. The OEM grease isn't (or wasn't) very good, and replacing it with a good "Marine Grade" grease that resists wash-out really helps.
ReplyDeleteI have no idea how old this unit is. All I know for sure is it was originally sold in SoCal, and used there until I somehow wound up with it. I've seen far worse ones from other places. I was "Jim's Home for Wayward Yaesu Satellite Rotors" when I lived back there. Had the ones I'm keeping, which were NIB when I got them from a friend, and FIVE other sets. I've had a bunch of these apart, so other than getting greasy a bit, it's not Rocket Science.
Oh, BTW....Yuasa makes batteries; no relation to Vertex-Standard who owns Yaesu.
If it's not one thing, it's another... sigh
ReplyDeleteThis is the first one of these I've rebuilt where the screws didn't come out (somewhat) easily.
DeleteNo biggie, but it proves the old meme that "Every 20 minute job is one broken (or seized) bolt away from being a three day project"!
For breaking stuck bolts loose, there is an air hammer attachment that drives the impact runs down the length of the screw, and you provide the torque. I saw Mustie1 use one on a bolt that probably would have broken if he had used an impact wrench. (He works on a lot of old rusty junk on YouTube.)
ReplyDeletehttps://www.amazon.com/Shake-Break-Impact-Screw-Remover/dp/B000BHJ7JM
Mayhew makes them to take 3/8 or 1/2 inch drive sockets, with a hex that you put a wrench on.
Not having an air hammer, I tried to simulate the effect with a hammer drill and a cobbled up thrust bearing - did not work.
I did have a surprising success using the vibration from a Dremel engraver to get a drive pulley off a splined mower spindle. We had been unsuccessful with a hydraulic press and destroyed the pulley. I applied PBlaster and went around the pulley hub for about 10 minutes and was able to use a regular puller to finally get the thing apart. I don't know if that kind of vibration might have helped with those screws or not, but it's one of those "stupid but it might work" things to keep in your back pocket.
Interesting tool. These are small screws, 6mm, and I was afraid I might twist the heads off, which is why I slotted them as deep as I could.
DeleteThe heat gun on the boss they screwed into really did the trick once I could get a good bite on them.
Probably should have gotten out the big heat gun from the start...