What is this Part from a Sioux Air Sander?

[Gannz]

Sioux 1287 Air Sander Rebuild

I picked up a 1287 sander/grinder from a yard sale for $1. It works and it's in decent shape once you get past the years of dirt and grease. I can't just use it as is though. Need to tear it apart, clean it, lube it, and replace any o-rings and gaskets.

This is the version without a trigger on the bottom. It has a thumb throttle on top and two screw stops that I guess are to access/remove the throttle mechanism. I separated the throttle handle from the exhaust housing and removed those two screw stops. I thought I was careful to catch any loose parts but while I was cleaning and turning it about, I discovered this part on the bench. I assume it came out of one of those two screw holes. It looks like a check ball but it's not completely round. It's flat on one "side". Not the best photo but hopefully you can see the flat spot.

I did locate a parts diagram but it's not for my specific unit. The one I found only has one screw stop on the bottom and mine has one on the bottom and a smaller one on the side. Anyone know for sure if this is a check ball or some other part I need to re-install? Don't know what it would be called but it looks like it would maybe go in the side port/stop and mate with the the indents on the throttle crank/pin to hold it locked in the on or off position.

I'm also about to contact the manufacturer but you guys usually answer faster... do they make a rebuild kit for these sanders?

 

[Gannz]

I continued the tear down and found a bearing on the governor side of the exhaust housing that's missing a few balls. Pretty sure that unidentified ball came from there. Must have been stuck in the gunk inside the throttle handle.

How do I separate the rotor assembly to change the bearings? Only one is shot but I might as well change both while I'm in there. Pull from the gear side or the governor side? Doesn't look like I can press from either side.

Or, does the governor spindle pull out? Hate pressing or pulling too hard on things if I don't know for sure they're supposed to come apart. If that spindle comes out, the rest of it will slide right off and then I can press out the bearings. Notice the "off" on the governor frame. Wonder if that's a clue?

The bearing on the gear side is barely pressed into the front end plate and that end plate has just a small opening for the spindle to fit through... the bearing or spindle can't be pressed thru that side.

 

[Gannz]

Nevermind. LOL. I just got it. I wrapped a rag around the gears and very gently held them with channel locks while cranking the governor frame with a wrench. The governor threaded off and the rest of it came apart.

The balls in the bearing are the same exact size as the "unknown" ball but that one does go in the side stop. There's a spring in there also and the ball "locks" into the cam indents to keep the throttle in the on or off position.