Crystal for Omega 2374/6 Bumper - Interestingly size varies from 2374/1

Hi all, I recently picked up this old Omega 2374 Bumper at an antique fair for $60. From on-line research I believe it is a 30.10 RA PC circa 1945.


It's running and keeps reasonable time, however it's obviously had a lot of use.

I intend to have it serviced by my local watch repair guy who's done a great job on vintage Omegas and Seikos in the past. I'll leave it pretty much as it is but do want to get a new crystal as the current one is cracked and scratched so deeply that a polish won't cut it.

Can someone please tell me what is the correct part number for the crystal, either Omega or Replacement provider, and what the diameter of the crystal is? I live in New Zealand so if you can point me to the item via on-line retailer or to the correct listing on an auction site that would be great.

Thanks in advance for to anyone who can help.

So I got up the nerve to take out the movement and crystal and measure it. The crystal is 31.2mm and the grove in the case the crystal fits into is 31mm. The movement is 34.8mm (w/o crown). I do have a digital micrometer and checked my measurements. Note the working watch above is a 2374/6 and its case back outside is plain.

NOW this is interesting. I have a donor watch I got for parts to fix the above. The donor watch shown below is a 2374/1 (H) and it has a slightly larger size crystal and case. It's crystal is cracked and has a chunk out of it and I think it was a loose fitting replacement, it's a 31.5mm crystal, fitting in a 31.5mm grove in the case which is 35mm. The marking on the outside claims this Omega is Waterproof which seems a big claim for a watch with a push-in crown and push-on case back, but maybe some rudimentary waterproofing explains the slightly different case sizes?

Interesting that there was variation between the different 2374 cases, so I think I'm looking for a 31.2mm crystal for the 2374/6 case or a (maybe?) 31.6mm armed crystal for the "waterproof" 2374/1?

Whoops, sorry I meant the CASE (not the movement) of the 2374/6 is is 34.8mm (w/o crown).

First of all, congratulations, you chose one of the nicest Omega and Omega's first automatic.
To determine the glass size, you measure the case once cleaned not the old glass. If someone make a mistake it will go one untill the end of times. Cleaning the case is very important before measuring. If you are going to give it to a watch maker let him fit it with a generic glass, this one does not need a specific Omega glass. Choose the flatest glass for aesthetic reasons.
This Omega is indeed waterproof and has a China lacker seal, if you have the tension ring that should seal the case back.
My SM 300 also has a push- in crown and is considered a diver by some. Waterproof does not mean you have a diver's watch.

I like the 2374 a lot, they are often missing the locking ring on the back, I have noticed.

Thanks Al, I see from another thread that's: 062PN1094 GLASS PLEXI D31.4 H3.35
So looks like that is for the 2374/6 non-waterproof in my original post.

Can you supply the Crystal Part Number AND Diameter for the waterproof 2374/1 (H) donor watch in case that can be restored as well?

Thanks for your help
Paul

Yes interesting that the donor 2374-1 H has a noticeable larger crystal. The (tight) crystal from the 2374/6 slops around in the 2374-1 case.

Guess I'll get a 31.9mm or 32mm generic crystal for the 2374-1H waterproof if it turns out to be fixable.

This is a bery helpful thread. I found a similar Omega watch online on Ebay.