Strange issue with Rolex A21j crown/stem

[george84]

So I bought a 2 tone A21j rolex sub from an RWG member. Worked fine for the first couple days I owned it. Now I have a bit of a perplexing issue, hopefully you guys can point in the right direction with.

If I wind the watch or turn it a few times to get it started and I have the crown all the way screwed down, the watch will work for between 10secs and a minute before the second hand stops ticking. However, if I do the same to get it started and I leave the crown completely unscrewed down, then the watch works fine like it is supposed to. What kind of issue am I looking at here?

I am a relative newb to this, so would it be worth fixing (by either myself or someone who knows how to operate on it), or better to just buy another?

[jmb]

Sounds like the stem might to be trimmed just a hair. I've had a21j watches do the same thing... As a test, screw the crown all the way down and then back it off about 1/2 - 1 turn and see if it runs OK.

[george84]

Sounds like the stem might to be trimmed just a hair. I've had a21j watches do the same thing... As a test, screw the crown all the way down and then back it off about 1/2 - 1 turn and see if it runs OK.

I just did a half turn screwed down and it ran fine. Now I am doing a full turn screwed down to see if it runs fine. I suppose I will keep doing half turns screwing the crown down to see where the "breaking point" so to speak is.

[jmb]

If it runs fine turned out 1/2 turn then the stem needs to be shortened just a bit. It's not that hard if you have a few basic tools and have good mechanical aptitude.

[fakemaster]

Yep too long.

[george84]

Ok guys thanks for the diagnosis, can anyone explain how I could shorten it?

[Francisco]

Ok guys thanks for the diagnosis, can anyone explain how I could shorten it?

remove stem from crown (unscrew it). probably you have to put the crowm-stem in boiling water to facilitate this task.

cut it a bit. check if the new length is OK.

put a small drop of loctite in the stem and screw it again in the crown

Edited May 19, 2010 by Francisco

[Brightight]

I would suggest filing rather than cutting if the difference is half a turn on the crown. It's easy to take too much off, do a little bit, check it, then do some more if that hasn't worked.

[preacher62]

No doubt...use a file. It will take off more than you think with just a few strokes.

After filing then take a stone and smooth up the end (kinda round it off) before screwing the crown back on. The rough edges left from the filing can cut the threads out of the crown...don't want that.