This is a Ford timer, right?
Is it aluminum? Does it have Ford script? If so,about 1915.
It looks like an original Ford roller timer for 1915. Ford script came in 1916 when the timers were cast iron.
That timer needs to be removed and cleaned every 1000 - 1200 miles or every year. Pack it with new grease and you are good for another 1200 miles.
Here is a link to proper care of your timer:
http://www.mtfca.com/discus/messages/179374/193779.html
Here is a 1916 - 19 timer in cast iron:
I had Toy Wilshire redo both my aluminum and cast ford script ones to use the carbon brush. A lot of worries not to have .
Jack, that sounds like a good idea. In the past, I had Frank Fenton rebuild a bunch or original Anderson cases and a few early Ford aluminum cased timers. They've worked great for me, but I've been intrigued by the TW design ever since Ron posted information about it. Perhaps I'll have him do a couple aluminum ones for me.