Robert sent this El Primero in, as it doesn’t reset properly, and the chronograph in general doesn’t work as it should. Winding is a bit noisy, too. He has had the watch from new, and it’s only 7 years old [correction – Robert told me it’s 10 years old], so I don’t expect any major damage.
There are lots of dirt particles in the watch, and they must come from within, as the watch is waterproof.
The El Primero, the pinnacle of chronograph movements, beating at 10 beats/second.
My Witschi timegrapher refuses to pick up a signal, and my cheap Chinese one shows this image. The balance is hardly swinging, and that erratically.
With the rotor removed, I can work my way through the chronograph layer.
The central chronograph runner has its top pivot broken – no wonder did the movement not reset properly. I only discover that when I reassemble the movement, though, but as it’s in the photo here, I thought I’d mention it.
There is a lot of dirt here as well, and there is a reason for that…
The pinion of the ratchet wheel driving wheel (1482) is half worn away. This pinion transmits the winding power, no matter if automatic or manual winding. But it shouldn’t be that worn after 7 years!
Under the crown wheel, a lot of dirt as well.
Now for the bottom plate…
Quite a complex winding/setting construction, with a quick-set date on the third crown position.
As usual,l the unlocking date spring is broken, leading to a very sluggish date change. There is a replacement of different construction available, that will hopefully not break.
All clean and ready to go.
Even though the barrel of the 405Z can be opened, I can’t get hold of a replacement spring, and I fit the old one. We will see later when we can an amplitude if that was the right decision.
I start off with the base movement. The new ratchet wheel driving wheel is in place.
Looks like the old mainspring is still very good!The new chronograph runner has arrived. Not cheap at £87.34!
The new unlocking date spring in place, and it looks a lot sturdier than the previous one.
The chronograph is working, and the depthing adjusted.
The complete bottom plate.
When casing the movement, I notice that the central second hand slips on its tube. I very carefully solder the hand to the tube, as you can see above. A tiny amount of solder will do nicely.That of course damaged the paint of the hand, and I order in some orange luminous paint.
Hand painted, and luminous compound in the tip re-applied.
Watch cased, waterproof tested, and ticking happily.