In Reply to: How did my governor balls get rusty? posted by Mark on March 07, 2018 at 07:44:12:
When any machinery sits idle, internal condensation starts to remove the oil film, and those unprotected parts start to rust. When that continues for several years, any protective oil film is long gone.
If your 9N has the oil line to the governor, make sure that line isn't clogged. If yours was made prior to when they added the oil line for the governor, consider adding that oil line (if your new governor has the fitting for it). If this is a very early 9N, the originality of not having that oil line may win over having improved oiling.
Frequent use will keep your balls well lubricated and rust-free.