Difficulty of Replacing Case Tube?

Posts
510
Likes
929
My Pre-Bond midsize Seamaster (ref 396.1042) runs fine, but screwing in the crown is rather tenuous. It is very difficult to catch the threads, and, once caught, the crown only rotates about a half-turn. It also does not sit flush against the case. I presume the crown and case tube are on their last legs. Since this is a quartz watch that serves as my beater, I'm not inclined to spring for a full service. What I am considering, though, is replacing the case tube and crown myself. The case tube (090ST0349) is friction-fit, so it seems like a tool such as the Horotec MSA03.657 would make quick work of the job. Press the old one out; clean the case, and press the new one in. I have done enough (very) amateur watchmaking, however, to have discovered that things are not always as simple as they first appear. If anyone has any experience, advice, or comments, I would welcome them.

And as long as I'm asking, would anyone know the part number for the replacement crown? I know that the first generation of this reference used the six-lobe 069ST42113M, but my watch is the second generation with the traditional round crown.

Thanks in advance.
 
Posts
27,826
Likes
70,690
Many Omega press fitted tubes on dive watches are nearly a blind hole, with only a small hole for the stem. So pressing the case tube out from the inside is not always possible. You would have to use an extractor type tool. You would only know for sure by opening the case and checking from the inside.
 
Posts
510
Likes
929
Many Omega press fitted tubes on dive watches are nearly a blind hole, with only a small hole for the stem. So pressing the case tube out from the inside is not always possible. You would have to use an extractor type tool. You would only know for sure by opening the case and checking from the inside.
Thanks so much for the heads up @Archer Based on a quick look, my 396.1042 may have a full opening on the inside. If I can figure out the crown part number, I'll take a closer look to confirm the case opening before taking any concrete steps. If the tube can't be pushed out from the inside, I expect I'll leave it for a professional once the threading wears out completely. The extractor type tools look like they could do serious damage in the hands of an amateur (e.g. me).
 
Posts
27,826
Likes
70,690
Crown for steel case is 069ST42113M.
 
Posts
510
Likes
929
Crown for steel case is 069ST42113M.
Thanks again for the info @Archer, but that's not the correct crown for my version. 069ST42113M is the six-lobed crown for the first generation 396.1042, but Omega changed the crown (and hands and bracelet clasp) in the second generation of that reference. The crown for my watch is a traditional ribbed, circular crown. This post has further details about the reference and its variants.

This is one reason why finding the correct crown has been difficult. All the sources I've found only show the first generation. I might end up using a 069ST42113M and living with the mismatched crown, but I'd rather find the correct one.
 
Posts
27,826
Likes
70,690
Thanks again for the info @Archer, but that's not the correct crown for my version. 069ST42113M is the six-lobed crown for the first generation 396.1042, but Omega changed the crown (and hands and bracelet clasp) in the second generation of that reference. The crown for my watch is a traditional ribbed, circular crown. This post has further details about the reference and its variants.

This is one reason why finding the correct crown has been difficult. All the sources I've found only show the first generation. I might end up using a 069ST42113M and living with the mismatched crown, but I'd rather find the correct one.
Well, Omega disagrees with you, as that is the only crown shown...
 
Posts
510
Likes
929
Well, Omega disagrees with you, as that is the only crown shown...
Unfortunately another example of Omega's official information being incomplete. There's ample photographic evidence of the crown change in for-sale listings in addition to the post mentioned above and Chronopedia:
Correct early models up to circa 1989 have a 6-eared lobed screw-down crown with Omega logo. Later models have a conventional ribbed screw-down crown, again with Omega logo.
as well as comments here from, for example, @padders
In fact there were several changes over the life of the Pre-Bond, to movements, hands, crowns, clasps ...
and @dialstatic:
Both the stick/sword and the Mercedes hour hands are correct. Mercedes occurred the earlier version commonly known as Type 1, which is defined loosely by a combination of differences in the hour hand, the crown, the caseback and the integrated bracelet clasp.
I've been trying to match the measurements of my crown against suppliers, but most just provide the part number and/or reference.

But I really appreciate you taking the time to look. Thank you.
 
Posts
27,826
Likes
70,690
Unfortunately another example of Omega's official information being incomplete. There's ample photographic evidence of the crown change in for-sale listings in addition to the post mentioned above and Chronopedia:

as well as comments here from, for example, @padders

and @dialstatic:

I've been trying to match the measurements of my crown against suppliers, but most just provide the part number and/or reference.

But I really appreciate you taking the time to look. Thank you.
I think you misunderstood…there is only one crown available for this right now…no others…
 
Posts
510
Likes
929
Oh. Okay. I was assuming (hoping?) that the later crown might have been used for other reference(s) as well as the 396.1042 and might, therefore, still be available from some suppliers under those reference(s). But the fact that I can't find an available crown that matches the dimensions from any supplier does lend credence to the later crown only being used for this one reference and/or (in any case) no longer being available anywhere.

Thanks again for your help and patience.