Movement stops after a minute

[martint]

Hello,

I’ve been ‘lurking’ on here for some time and seen a great advice and hoping now someone can offer some for me. I don’t think I’ve missed a similar posting.

I am trying to restore my father’s watch in time for Christmas. It got wet in a torrential downpour some 15 years ago, it stopped running and was left in a drawer. It has an ETA 2452 movement.

It was quite a mess when he gave it to me “to see what I could do with it”. Very stale oil mixed with water didn’t smell great and obviously some resulting internal corrosion too.

I have cleaned the parts and replaced those that looked damaged. I have installed a brand new complete balance and other parts replaced from donor pieces.

I completely reassembled the watch (minus hands, dial and case) but found it would only run for very short periods. Dial up or Dial down appears to make little difference.

I dissassembled and re-assembled up to a complete train of wheels and escapement with power and setting.

I have found the watch runs but stops at around a full minute, typically one minute but can run for two or three but always stopping around the full minute mark, at least within a margin of error for me hitting the stop on my timer. The escape wheel comes to a gradual halt, the pallet moves weakly back and forth without the escape turning and then the balance gradually comes to a stop.

A light touch on the escape pivot or train wheels/pivots is enough to have the watch continue running again… for a minute.

I have very closely inspected the third wheel, fourth wheel and escape wheel in particular and can see no obvious sign of damage. Nor do the jewels appear damaged. I don’t posses a truing caliper so its possible there is some small misalignment in the pivots I guess creating some friction? Before I try and source replacement wheels I thought I would ask if anyone here had experienced a similar problem or could offer any advice? All gratefully received.

Thank you.

[nickelsilver]

Have a good look at the 4th wheel, likely a damaged tooth or something stuck in between two teeth.

[yankeedog]

Maybe some left over corrosion.

[martint]

Thank you so much for the feedback.

I've inspected the 4th wheel especially again and can't see anything amiss. 

I'm going to clean the wheels again and retry.

[Nucejoe]

Hi martint,  when stopped, mark a dot( majic marker) on the escapement wheel ,say the tooth engaged with a pallet jewel, get the movement to run and see if stops at the point, repeat to increase validity of the collected data. Do the same(Dot hot spot) with the minute wheel. The collected data can by itself point out the fault, report if you will your observation on the forum.Brings in more advice.

In case you disassemble the movement mark the corresponding tooth on gear/ pinion on arbors, escape and minute as well, as a simple operation with razor blade may be all required.

Regards joe

[Nucejoe]

While at it, if you loosen the cabs jewels on escape and fourth wheel and drop a droplet of lighter fluid on escape and fourth cabs and why not on fork arbor and balance jewels.

If no noticable difference remove balance with cock and the fork, manually wind ( normal wind speed) to run the oiled train for a minute or more.

Oil the inside of center tube and once you gain access clean tubes inside by making  use of the seconds wheels shaft as a tool.

Once these are checked and fault not found, I will send you pix on safe brush cleaning of a wheel before you resort to buying new one.

Regatds joe

[martint]

Thanks Joe, some useful advice there. I will reassemble and try marking the sticking point to see if the narrows the issue.

The train appeared to run quite freely when I've previously assembled. I've always used 9010 on the pivots and 9415 fork.

Prior to this round of cleaning I took a photo of the main suspect. This was one of the original pieces.

I'll report back when reassambled.

Thanks again.

[martint]

Hello All,

I thought I would update as I think I found my problem.

I looked closely again after cleaning and a little embarrased to report that for all of my focus on teeth I missed a slight kink in the sweep seconds wheel itself. I straightened by hand as best I can (probably enough to be in a level of tolerance) and have reassembled the train and things seem to be running continuously now.

Will work on completing the reassembly and getting it on the timer. I feel better about being complete for Christmas!

Thank you all for your feedback. I appreciate it. A lesson learned I think.