Vintage Windmill and Wind Generator Forum

Update:
I did do the stop leak, and then JB weld. A couple of hours of sitting on my workbench filled with water, and I saw no leaks. Yay. I painted the hub, reassembled the motor, and proceeded with the rest of the rebuild.

I installed the mill (B602) a couple of weeks ago, looked great. Bizarrely, though, the screw in pump rod did not want to screw all the way into the yoke in the motor. It seemed like the rod wasn't quite threaded long enough to screw in far enough to install the cotter pin. So, back to the shop to locate a different pump rod, and then it took a couple of weeks to find a day that worked for both me and the owner to come back.

Today was that day, and I successfully installed the replacement pump rod. However, much to my dismay, I discovered that the hub is now leaking oil out the front end. Of course, it's hard to stick your head through the spokes and look at the outer end of the hub, but when I reached out there and felt with my fingers, it seemed like the JB weld had cracked. I was tempted to keep my mouth shut, but my conscience got the better of me, and I told the owner what's going on, and said I would do some research and come back.

I am thinking that JB weld makes a Marine Weld product that will allegedly set underwater and is even stronger than the standard stuff, so maybe that's the next thing to try. Any other ideas?

JB weld makes a water weld as well. I can’t say I have tried either the marine weld or water weld, but it is worth a try.

In my limited shaft replacement experience on Aermotors, I have used some gasket maker when inserting the key.

CTXmiller wrote: Tue Sep 30, 2025 7:31 am In my limited shaft replacement experience on Aermotors, I have used some gasket maker when inserting the key.

Good idea. In this case, I was using the original hub with the originally installed shaft, so the key was also already installed.

I did poke some epoxy putty down into the keyway on the inside of the hub, to try to seal the keyway at that end, then also put a layer of JB weld over the outer end.

Is it leaking enough to even worry about? An aermotor isn't exactly sealed anywhere as you know. Maybe see if its enough to run down a spoke.

With the oil on it now it may be tricky to get anything to adhere well. Maybe if you bring some lacquer thinner and have a way to blow it off (keyboard duster can or something) you can get it clean enough.

Otherwise is there enough of the main shaft to peen more and get a tighter fit in the hub and around the key area?

It was leaking enough to see, from the ground, dark oily stains on the wheel, and the brake was slipping.

I pian to spray the whole hub with a brake cleaner product, which has nasty stuff in it like xylene or acetone.

When I had the mill in my shop the shaft looked very thoroughly peened and did not seem discernibly loose at all. Now I wish I had welded it to the hub. I'm not sure I could beat on it hard enough to actually peen it while the mill is on the tower. Kind of awkward trying to reach out through the spokes to the front of the hub, not very ergonomic for leverage.