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PaulnKC

How to open this old Benrus...

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Greetings all.

I recently acquired a moderately old Benrus 3-Star Automatic wristwatch. It's a #7026 Series.

I believe these are from the 60's - though I don't know much about them.

On the back of the case it says "open through crystal". Which makes me think that the Crystal should be removed using a Crystal Lift - and the movement lifted out through the bezel.

Of course, the stem (presumably two-piece) would have to be separated prior to - or during the operation.

BUT - after some googling - I have also heard tell - that the case-back should be pushed out by pressing on the crystal with thumbs. These seem to be incompatible methods - but I really have no idea - as I have never seen a case like this. 

 

Does anyone have experience with this type of case from Benrus? I can post pictures after I get home - if they are needed.

 

Many thanks!

-Paul

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This is a typical benrus case they been making these since the 40s. You have to remove the crystal using a brass jaw type crystal remover. Once it’s out you have to separate the split stem. I could explain how to do it but a video is much easier and there are plenty out there. Just do a search on the net “ how to remove a split stem” and there is a tutorial on Esslinger.com on how to use the crystal remover.

https://blog.esslinger.com/how-to-replace-a-watch-crystal/?_ga=2.79089757.839292711.1581400550-1065094695.1581400550

what i will suggest is to use a wire cutting plier and go from the outside of the case not between the movement and the case to avoid damage. Do not pry just allow the tapered shanks of the pliers to pull it as you close down. You may need to do pull it a bit yourself just make sure you pull straight don’t wiggle or pry. It may take some force so don’t be shy with it.

do not push on the crystal and remove crystal before separating the stem

Edited by saswatch88

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1 hour ago, saswatch88 said:

This is a typical benrus case they been making these since the 40s. You have to remove the crystal using a brass jaw type crystal remover. Once it’s out you have to separate the split stem. I could explain how to do it but a video is much easier and there are plenty out there. Just do a search on the net “ how to remove a split stem” and there is a tutorial on Esslinger.com on how to use the crystal remover.

https://blog.esslinger.com/how-to-replace-a-watch-crystal/?_ga=2.79089757.839292711.1581400550-1065094695.1581400550

what i will suggest is to use a wire cutting plier and go from the outside of the case not between the movement and the case to avoid damage. Do not pry just allow the tapered shanks of the pliers to pull it as you close down. You may need to do pull it a bit yourself just make sure you pull straight don’t wiggle or pry. It may take some force so don’t be shy with it.

do not push on the crystal and remove crystal before separating the stem

Thank you saswatch88.

I have a crystal lift coming tomorrow - I'll try using that.

-Paul

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If this is one of the watches where you press on the crystal, you should be able to see a cut-out around the crown area which allows the crown/stem assembly to move downwards. But since it 'specifically' mentions open thru crystal then that is exactly what you need to do!

Anilv

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if it is a two piece stem , i usually tilt the movement up and slowly turn the stem.( which is split) when the movement is at its highest tilt the split is perpendicular to the case  and the movement can be removed.. 

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6 hours ago, clockboy said:

Agree with oldhippy pics are required.

Clockboy (& oldhippy),

I will post some pics this evening. I probably should have done that yesterday when I got home.

As always,  thanks very much for sharing your expertise.

-Paul

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9 hours ago, PaulnKC said:

Clockboy (& oldhippy),

I will post some pics this evening. I probably should have done that yesterday when I got home.

As always,  thanks very much for sharing your expertise.

-Paul

Here are the pics.

I suspect the first one (back) is all that's needed. But including a shot of the front as well.

P2122186.thumb.jpg.27f78f06f26647eea98beb7d348acc0a.jpg

and the front...

P2122188.thumb.jpg.a769d1210c67101f8388edca90bacffc.jpg

 

Thanks!

-Paul

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12 hours ago, yankeedog said:

Yup..remove crystal  tilt movement  out as previously  discussed. If I remember  these have a very nice ETA automatic. 

The rotor is signed Benrus Model FE 2D1. The Base plate is marked UI 2451. Which is apparently an ETA 2451. The auto-winding mechanism is affixed with blue screws - so, at least a somewhat nice movement.

I am not familiar with these. The rotor is super noisy. Don't know if that's normal for this mechanism. Or if something is wrong.

This one is going back to the seller for a "re-check". It keeps pretty good time but the timegrapher traces are all over the place. Even with the movement removed (from case) - and held directly in the timegrapher.

-Paul

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1 hour ago, PaulnKC said:

The rotor is signed Benrus Model FE 2D1. The Base plate is marked UI 2451. Which is apparently an ETA 2451. The auto-winding mechanism is affixed with blue screws - so, at least a somewhat nice movement.

I am not familiar with these. The rotor is super noisy. Don't know if that's normal for this mechanism. Or if something is wrong.

This one is going back to the seller for a "re-check". It keeps pretty good time but the timegrapher traces are all over the place. Even with the movement removed (from case) - and held directly in the timegrapher.

-Paul

Here are a couple of pics of the movement...

P2132189.thumb.jpg.40dd7e181e02a97f206fa35546491927.jpg

P2132190.thumb.jpg.a5482d7a0b5aa74b4306dbb1002c6616.jpg

-Paul

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Sorry I didn't get back sooner. Because I lost Cookie my cat I wanted some time to myself. Nice to know you had the help you needed and it was successful. Keep up the good work. Members on here always like to help. Photos really help.  

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Hi Paul, Looks clean.

ETA 2451 and its family are true work horse. Rotor should be quite, normally can,t be heard and hardly ever develops a fault, if no slack and falls under own weight, should be OK. If it rattles, check winder module, clean lube reversers.

If the rest of the watch looks good , could be for keeps.

I thought you was going to service it yourself. 

 

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2 hours ago, oldhippy said:

Sorry I didn't get back sooner. Because I lost Cookie my cat I wanted some time to myself. Nice to know you had the help you needed and it was successful. Keep up the good work. Members on here always like to help. Photos really help.  

oldhippy, I am so sorry to hear about the loss of Cookie. My wife and I foster homeless cats and dogs. Plus have several of our own. Take solace in the fact Cookie had a great life with you while she was here.

 

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1 hour ago, Nucejoe said:

Hi Paul, Looks clean.

ETA 2451 and its family are true work horse. Rotor should be quite, normally can,t be heard and hardly ever develops a fault, if no slack and falls under own weight, should be OK. If it rattles, check winder module, clean lube reversers.

If the rest of the watch looks good , could be for keeps.

I thought you was going to service it yourself. 

 

Thanks Nucejoe.

Yes, I would normally (try to) do everything myself, but in this case, the watch was supposed to have been serviced. So, going to give the seller a chance to make it right. Having said that, I may be trying to sort some things after I get it back.

So, I may add on to this thread for more help, as needed.

Thanks!

-Paul

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