I have an A Lincoln that just has no pep, even after cleaning. I measured the mainspring and find the existing spring is 3.00 mm wide and everything I can find states a 2.7 is the correct width.
That would explain why the barrel cover doesn't close properly and the mainspring seems to "drag" when the barrel bridge is tightened. I'm hoping correcting the mainspring will correct watch performance.

As I work through all of the spec's, I'm not sure which spring is correct. I viewed and printed the appropriate pages from Frank Kusumoto's on-line catalog. But, I'm still not sure.

Here are the watch specs: 16s, A Lincoln, 21j, GJS, 5 adj, SN 3,499,755, OF, 3/4 plate.

I think it's a 9th model. The existing Mainspring has a double brace and the Swartchild literature confirms that is correct. Marshall's literature tells me it's 2.70 width and .18mm strength and factory # 47314. Using Frank's literature posted here, there is a whole different series of Factory part numbers. Can someone please help clarify what is the correct mainspring number. And the big question, where can it be purchased?

Thank You,

Bill

William that,s right 2.70 width X 20-1/2 in. long. the # 47314 will work..

I have been working on this A Lincoln on and off for over six months and the problem was an improper mainspring! It's now running nicely!

Thank You,

Bill