I created an assembly.

For some reason, one particular part (right gear in attached image) is causing a problem. When I close/reopen SW 2014, some of the features of the part disappear. It is almost as if the gear is returning to its original default state before I edited it. 

Oddly, another part that is also a gear is not having this problem.

I tried copying the problematic gear and pasting in that copy, but the problem remains.

How do I fix this? Please help!

Thanks.