A customer has sent in his Wyler Heavy Duty 660. It’s not running very well and needs a service. I have a soft spot for divers without bezels and think this looks very cool!
The amplitude is very poor and the watch is gaining a lot of time. Wyler was very proud of it’s Incaflex shock system. The balance wheel has curved flexible arms that would absorb shocks.
I take the watch apart. The movement is a modified ETA 2354 they have their own mainspring that is marked by the riveted hook.
The movement is cleaned and ready to be put together. I start by putting the balance jewel assembly back together to see that the hairspring moves freely. I then fit the mainspring in the barrel and put the movement together.
Before the service the hairspring had oil making it stick. This causes the watch to gain time. Now that it’s clean it’s not sticking and working like it should again.