Jumphour Questions – FE-140-1A

Gigandet "digital" jump hour with a manual FE-140-1A

Issue:
The minute wheel and/or hour wheel appear to "bind" at about 50-55 minutes past the hour. It's running but the time display won't advance.

Questions:
1) what may be causing this?

2) suggestions for what tool(s) or techniques are requires to remove the minute and hour wheels?

Thanks and regards,