Cleaning Deteriorated Crystal Gasket "Goo"

[dpn]

Hello everyone,

I recently purchased a Zenith Defy (A3642) from 1972 with a 2562PC movement.

The watch is in overall gorgeous cosmetic condition. Per the seller, it was purchased new in 1972, worn briefly, and then put into a safe for ~45 years. I do not know its service history, but it is running decently (averaging -10 s/day with a low amplitude of 180-200). It may be that this watch has never been serviced. The movement absolutely needs an overhaul, but the good news is that the crystal, crown, bracelet, etc. are all original.

Unfortunately, the original rubber or plastic crystal gasket has deteriorated into a black "goo". Most unfortunately, some of this goo appears to have dripped onto the dial. It isn't fouling the hands, which is a plus, but it definitely appears to have stuck onto the dial.

 

Does anyone have any insights into cleaning this goo off of the dial? The dial is in otherwise gorgeous condition. I'm worried that there won't be an elegant way of pulling the goo off without damaging the dial. I'm also concerned about stains on the portion of the dial now covered in goo, but am happy to live with those if I can otherwise remove the goo safely.

In the same way, I hope to clean the goo off of the original crystal. This seems a little easier, but I don't want to scratch the crystal removing the stuff.

Thank you so much for any advice you might have. I am confident in my abilities to extract the movement from the case and remove the hands safely, but have no idea how to pull the goo off other than maybe prying it with some pegwood.

(There's no urgency in this matter: I'm currently hunting for the correct caseback opener and correctly-sized replacement gaskets, and the goo isn't currently fouling the hands.)

All the best,

Dan

[Nucejoe]

There is sure to be some goo on back side of dial plate, which you can test different ideas on.

I had a bellmatic dial with some stuff stuck on the face, some sort of sealant used on o-ring on back plate, whiped it off with tissue paper and acetone, turned out incredibly perfect.  Acetone is friendly to the paint of bellmatic dial. 

Good luck, you need it in this case.

[dpn]

Thank you Nucejoe ... Yeah, I'm worried about what has seeped onto the front of the movement from behind the dial.

I'm still looking for a Zenith caseback opener, so I don't know that the extent of the problem is.

Thanks for the tip!

[yankeedog]

Hmmmm.how to get it apart  in the gentlest manner.  I am concerned  that the dial  may be stuck to the case. If it is an acrylic  crystal  as it does appear  to be,maybe it would be best to remove  the crystal  first and clean  enough  to remove the movement/dial. Before proceeding  with a more thorough  cleaning.