← Back to overview

Got this as a non-runner, seller didn't know why it wasn't running. The listing showed a movement in apparently good condition but the hairspring is obviously mangled. Slight tension on the crown causes the hands to spin freely, so the excapement is also in bad repair.

The movement is Omega 601, and I got another 601 in the same lot. Price was very good so I'm hoping to get one runner out of the two. Caseback reference no. 135.070. serial no. 30,433,664 which dates it tp 1969. Lift angle: 49°.

Right off the bat, the pallet fork is just absolutely destroyed, and the hairspring was mangled to the point that it was somehow sticking out of the case. I can't even begin to imagine how this would happen. Looks like whoever was here the last time also dipped the entire movement in some sort of oil.

I took the pallet fork and balance complete from my donor movement and installed them into this movement to look for any other issues. None found, everything else looks to be in good working order. The movement runs.

The crown wheel had some rust on it, and it got the fiberglass pencil treatment. The movement was very filthy and full of oil. See how much gunk came out in the initial cleaning.

Also, the crown gasket disintegrated when I cleaned the crown. I've since learned that IPA can dissolve this gasket material and will take greater care in the future. Anyway, this was an opportunity to try my hand at replacing a crown gasket. I bent a thin sewing needle into a hook and managed to dig out old remnants of the disintegrated gasket. I then spent a long time trying to remove the crown washer while waiting for an assortment of new gaskets to arrive. There seems to be (at least) two methods of doing this that I learned from this WRT thread, the first being "hit it with a hammer". In not so few words, use a staking set to force the washer to bulge into the crown body itself. In theory (though sadly not in my practice) the washer's outer diameter will contract and release from the inner lip of the crown, allowing the washer to drop out of the crown.

No amount of banging did the trick for me, and I gave up. When the new gaskets arrived, I had no trouble lubricating a suitable gasket with silicone grease and coercing it into the crown. In other words, I never did try the "stuff crown with gaskets until washer pop out" trick.

Reassembly was uneventful until final inspection of the completed service: the seconds hand would tick normally, then jump ahead 2-3 seconds, stay still, and continue ticking. The watch otherwise keeps great time, so I did not suspect a broken tooth in the gear train. Turns out the friction spring that keeps tension on the sweep second pinion acts like a chronograph minute jumper spring... This WRT thread discusses the friction spring and its placement.