I have an Elgin convertible grade 48 13J movement that I cleaned and reassembled. The watch was running before cleaning but not well and I did not check all positions. After cleaning and assembly the balance wheel spins for a few revs and then stops with the roller jewel between the banking pins. If you press on the top of the movement on the center wheel the balance moves for a few revs then stops. If you press again it will do the same thing and sometimes the balance will start and not stop but has low amplitude. If you let it run it will gain amplitude and run all day and over night. In the morning if you turn the movement over the balance will slowly come to a holt. If you do the same procedure as above to get it to run it will run face up all day and night. Does anyone have a suggestion? I have taken the movement apart several times and there is no cracked jewels or bent pivot on the balance. the center wheel is not bent either.

thanks
Larry

Larry

I suggest starting with the balance. Let down the mainspring and take out the pallet fork. Now check the balance wheel for spin - gently start it moving. I use an artist's brush. Does it spin for several seconds in all positions? If not, is there sufficient endshake? Is the hairspring flat? Is the hairspring between the regulator pins?

Then, check the train for free movement. With the pallet fork out, wind the mainspring. Does the train run smoothly and slowly come to a stop or have some backspin? If not, disassemble and check each wheel independently to be sure they spin freely.

How is the mainspring? Did you remove it from the barrel and clean/oil it? It's unusual to have a spring so set that the watch won't run at all, but I've seen some very weak ones that reduce balance amplitude significantly.

Good luck with your troubleshooting. I'm sure you'll find the problem.

Doug

Thank you Doug. Yes I have done everything that you suggest and the balance is fine and spins free of the pallet fork. The hairspring is fine and between the pins. The trio runs free without the pallet fork. I did nothing to the mainspring. Again the watch will run when putting pressure on the center wheel sometimes and when it does run it will have low amplitude to start and then swings at a high amplitude. It is running dial down now since 5AM this morning. If tomorrow or anytime now I turn it dial up it will slowly stop and I will have to put pressure on the center wheel to try to start it again. Then it will run as described for the dial down.

Have you completely reassembled the movement, including the setting wheel and canon pinion? I'm wondering if something there could be too tight and causing a drag on the center wheel.

Doug,
Yes the entire movement is assembled. I do think there is an issue with the center wheel but can't figure it out.

thanks,
Larry

I also removed the setting wheel and canon pinion and that makes no difference in the running of the movement. Still hard to get it to start running on its own and have to press around the center wheel to get the balance to start moving. Takes about 1/2 hour of doing this to get it to start on its own and then it runs fine all day either dial up or dial down. If you move it from dial sown to dial up it slowly stops and have to go through this procedure again.

Larry

Larry

Found the problem. Second wheel had hardened oil on the top by the "jewel" and gear. Only could see it under high magnification. Cleaned it up and runs like a charm.

Larry

Glad to hear it!

Doug