“Dad’s Old” Longines 23Z Watch

Published: June 10, 2014

We service a lot of vintage Longines wrist watches (and a fair amount of antique Longines pocket watches, too).

Longines 23Z Front View

This shows the hands, dial, and case of a lovely Longines 23Z we recently services.

The watch repair we’re discussing today another watch that belonged to a customer’s father. Wayne, a customer from a Memphis area suburb, brought the watch to me with the hope that his dad’s watch wasn’t “too far gone” and that it might be possible for it to “run again.” Like so many customers, they had tried to have it at several watch repairs with no success. The unrepaired watch had gone into a box for years before Wayne brought it to me.

Wayne was delighted when I told him we could fix it. He left the watch with me to repair.

The watch was in a sharp looking 14k gold case and had a Longines 23Z movement. This was a fairly common movement and I still see them frequently in vintage Longines watches.

There are a couple of variations of the 23Z movement, and we’ve seen them all in the shop.

Longines 23Z Variations

  • 23Z – Hour and Minute hands with sub-second hand.
  • 23ZD – also has a sub second, but adds a date function.
  • 23ZS – hour and minute hands with a sweep second hand. The hand isn’t at the six o’clock, it “sweeps” around the dial through the center pinion, above the hour and minute hands.
  • 23ZSD – Hour and minute hands with
Longines 23Z Movement Dial Down Shot

This shows a fully serviced Longines 23Z movement.

Based on the serial number, I would date production of this watch to late 1952. Customers always seem to love the look, feel, and function of Longines watches from the late 1940’s and 1950’s, which is why the so frequently have them repaired.

We fully disassembled the movement. It was gummed up badly, the mainspring was broken, and the hairspring looked troubled. These are all easily rectified problems. We disassembled the watch completely, cleaned it, hand oiled it, and reassembled it.

The watch went from having a gummed up train of wheels to being absolutely free train of wheels. Check. This meant that after we adjusted, cleaned, and oiled it, everything had the correct amount of end shake and freedom, without having too much play. Everything was perfect.

With the train of wheel as it should be, we next inspected the pallet fork to make sure the pallet stones are perfectly level and that nothing has been moved or damaged after the initial inspection during disassembly. This was also fine, so we put in the balance – and a problem arose. I inspected the balance and found that the hairpsring was a bit out of true. We had missed that – the hairspring has to be perfectly flat and it cannot rub on anything around it, be it the balance wheel arms, the balance bridge, etc. As I went to true the hairspring, it quickly became obvious that I had missed something big – someone had mangled this in the past, badly. I spent an hour trying to reconcile the differences before it became obvious that the customer would be better served with a new hairspring. After contacting the customer, we did just that.

Once we serviced the watch, we carefully polished and cleaned the case, band, and crystal. A pet peeve of ours is overpolishing. You can make a case look great, but it is temporary, and over the years heavy polishing can be very damaging. Careful, minimal polishing is one of the greatest services we can provide to customers.

On final reassembly, the watch is keeping wonderful time. I consider this Longines watch to be a family heirloom. With regular service, it will make a stylish vintage timepiece that the family can be proud of for generations.

We fixed this watch, and we’d love to fix yours too. Please contact us about any watch repair needs you have at 800-251-1484.