[tmodelman]

Yes

You remove the timer (commentator) shell and then clean the inside of the shell, where the contacts are. Then clean the roller contact. All should be shiny.

Then oil the roller, the oiler cap on the top of the Ford style timer is for light oil each 500 miles. See the Ford Owners Manual, or the Ford Service book.

Now if you have an aftermarket brand, these may be wiper type, or flapper type, they mostly don't need cleaning or oiling.