When you go back together with it, don't forget to pre-load the bearings. Here's how if this is your first time installing axle bearings.
1. Tighten castle nut finger tight.
2. Tighten nut about another 1/4 turn.
3. Rotate hub/wheel about a dozen times.
4. If the hub loosens you will have to repeat from step 1. If not go to step 5.
5. Loosen nut.
6. Tighten nut finger tight.
7. Loosen nut just until you can install cotter pin into the hole in the spindle.
8. Install cotter pin into nut/spindle.
9. Check that the wheel turns freely and there is no binding or that it is not sloppy loose.
1. Tighten castle nut finger tight.
2. Tighten nut about another 1/4 turn.
3. Rotate hub/wheel about a dozen times.
4. If the hub loosens you will have to repeat from step 1. If not go to step 5.
5. Loosen nut.
6. Tighten nut finger tight.
7. Loosen nut just until you can install cotter pin into the hole in the spindle.
8. Install cotter pin into nut/spindle.
9. Check that the wheel turns freely and there is no binding or that it is not sloppy loose.