Unitas 285 497 running slow ?

[mountaineer]

I have a Unitas 285 497 running slow in a recent build. It loses about 5 minutes an hour. I adjusted the +/- lever, it really did not help.

I purchased the movement for a clock/pocket watch dealer on ebay. He said he fully serviced the movement. It is apparent that the movement was serviced, cleaned and oiled. I never tested the movement before my build.

I changed the 4th wheel to a "lower" no seconds hand. Added higher cannon pinion and hour wheel. I messed up the keyless works and took apart and re-installed.

The movement winds well and feels solid.

Any ideas where to start on diagnosis? I do not have a timograph. Is there an app for a cell phone that would help?

[Yoda]

Is it very easy to set the hands? In that case you have a cannon pinion with too low friction.

[mountaineer]

Is it very easy to set the hands? In that case you have a cannon pinion with too low friction.

It is not unusual to set the hands. If anything it is slightly firm to set hands but not in a bad way.

One thing that is a little strange, when I wind the watch and stop. The crown reverses about 1/4 turn.

[Yoda]

Is it very easy to set the hands? In that case you have a cannon pinion with too low friction.

It is not unusual to set the hands. If anything it is slightly firm to set hands but not in a bad way.

One thing that is a little strange, when I wind the watch and stop. The crown reverses about 1/4 turn.

That may be because of the click and ratchet wheel, nothing to worry about.

The issue remains, I wonder if it really was serviced and what else has been done.

[unreformed66]

You say that you changed the 4th wheel. Where did the replacement wheel come from? The 285/497 and 6497 are 18000 beat per hour movements. The 6497-2 is a 21,600 beat per hour movement. If you used the 4th wheel from a 6497-2 that would be a problem.

[mountaineer]

You say that you changed the 4th wheel. Where did the replacement wheel come from? The 285/497 and 6497 are 18000 beat per hour movements. The 6497-2 is a 21,600 beat per hour movement. If you used the 4th wheel from a 6497-2 that would be a problem.

I was thinking it might have to do with me messing with the movement... At first I thought maybe the 4th wheel pinion was different for a 6497 vs 285/497. (maybe larger diameter creating friction). The bridge was a bear to fit.

I do think the 4th wheel is for 6497-1. I got it from Otto Frei and it looks like that is all they have.

I might put the original 4th wheel back on and see what happens.

[Yoda]

You say that you changed the 4th wheel. Where did the replacement wheel come from? The 285/497 and 6497 are 18000 beat per hour movements. The 6497-2 is a 21,600 beat per hour movement. If you used the 4th wheel from a 6497-2 that would be a problem.

I was thinking it might have to do with me messing with the movement... At first I thought maybe the 4th wheel pinion was different for a 6497 vs 285/497. (maybe larger diameter creating friction). The bridge was a bear to fit.

I do think the 4th wheel is for 6497-1. I got it from Otto Frei and it looks like that is all they have.

I might put the original 4th wheel back on and see what happens.

Do that and be careful!

[P4GTR]

You say that you changed the 4th wheel. Where did the replacement wheel come from? The 285/497 and 6497 are 18000 beat per hour movements. The 6497-2 is a 21,600 beat per hour movement. If you used the 4th wheel from a 6497-2 that would be a problem.

I was thinking it might have to do with me messing with the movement... At first I thought maybe the 4th wheel pinion was different for a 6497 vs 285/497. (maybe larger diameter creating friction). The bridge was a bear to fit.

I do think the 4th wheel is for 6497-1. I got it from Otto Frei and it looks like that is all they have.

I might put the original 4th wheel back on and see what happens.

Last I checked they were out of the -2 wheels also. But it still sounds like a plausible culprit.

[djolemag]

5m/hour is too much. I would bet on cannon pinion loose...

Sent from my P30 using Tapatalk

[mountaineer]

5m/hour is too much. I would bet on cannon pinion loose...

Sent from my P30 using Tapatalk

I did change the cannon pinion to a higher one. Maybe I didn’t snap it down tight.