Stem removal problem on Seiko 7T34A and 7T34B movements

[Pict]

Hi, I am hoping someone here can shed light on these issues. I recently acquired two Seiko 7T34-6A09 Flightmaster chronographs. I was hoping to get one good watch out of them but unfortunately both movements have issues. One watch has the 7T34A movement and the other has a 7T34B.

The 7T34A is running but the 6 o'clock alarm register complication is sticking occasionally and doesn't keep pace with the main hands. Additionally when you set a time at the second click and then proceed to set an alarm time at the first click, pushing the crown back in to the normal position to deactivate the alarm and return the hands to the time set doesn't work correctly. The hands attempt to wind around to the time set but invariable stick at some point in the travel. Other than that, all other functions appear fine and keep time.

The other 7T34B movement is totally dead with a new battery.

I am thinking the 7T34A might be repairable as it looks from the speed of rotation that the alarm complication is labouring - it looks more like a friction issue than broken teeth, though I am guessing. I am thinking of trying to source a new 7T34 movement and put that in the better case (the 7T34A), and then maybe try and repair the 7T34A movement and swap that for the dead 7T34B in the other case. The crystals also need polished or replaced so initially I am trying to remove the movements. 

The 7T34B dead movement seems to have an issue with the alarm crown - it only will click out to one position not two, and the stem doesn't release from this (I presume) first click position when you push in the marked hole. Any suggestions as to how to coax it out?

The 7T34A movement has no holes marked 'push' and I cannot find any directions in the Technical Guide for stem release. Has anyone any idea of the correct procedure for this movement?

Thanks for any suggestions, and if anyone knows of a source of new old stock 7T34 movements I would be most grateful. Photo of a 7T34B attached.

[Pict]

Update - finally got the alarm stem to release on the 7T34B movement. Still scratching my head about how to release both stems on the 7T34A.

[GeorgeClarkson]

Hi Pict, please check the walkthrough section where I posted a series of videos where I tackle the disassbly of a 7T32 movement. It is essentially a downsized 7T34 so 95% identical to it.

The release of both stems is identical. Need to just find the right holes that are in the same position as the 7T32 movements and press the lever that shows in them with a thin pin.

[Pict]

Thanks George. The cover plate is different on the 7T34A and has different hole layouts and nothing marked 'push' but I think the corresponding holes for stem release should be the ones circled in the attached image. I'll try them out later today and confirm whether this is correct.

Regards,

John

 

[clockboy]

This PDF should help.

 

Seiko 7T34A - Technical Guide.pdf

[Pict]

Thanks. You would think that it would help but I've been through it a dozen times and can find no mention of the stem removal method. This is in contrast to the 7T34B Technical Guide which is very clear and has a dedicated diagram pointing out the release holes.

 

[vinn3]

i like that  tech. guide.  thanks  vinn

 

[Pict]

Update - figured out the stem release method for the 7T34A movement. For the 4 o'clock position alarm crown stem, the release is available at the circled hole when the crown is one click out from normal. You can see a lever with a dimple appear in the hole at the first click. Approximate location of dimple to press is at the red dot.

The main crown stem at the 3 o'clock position is a bit more obscure, but again if you pull the crown out to to the first click you can see a dimpled lever appear down the space to the left of the dimpled tab in the green circle. Approximate location of dimple to press is at the red dot.

In both instances space is a bit tight to use tweezer tips to disengage the stem. I used a blunted sewing pin which worked great.

Hope this helps someone out.