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Discussion Starter #1 (Edited)
Hey everyone, I'm looking for information on fixing a Seiko Chronograph Model 7T62-0CD0. Currently, the crystal is cracked severly and neither button seems to work - they press into the watch OK, but nothing happens. The watch still keeps good time, though. I'm interested in attempting to fix as much as I can myself, but while I'm somewhat mechanically inclined, I'm a novice at watch repair. I have a basic set of tools and have replaced the battery, though.

1: How do I figure out the size of the crystal so that I can order a replacement?

2: Do you have any recommendations for where to order replacement parts from?

3: Is there anything that I can try to fix the buttons that doesn't involve taking apart the movement? (Edit: The buttons both work, the problem's with the hands. See below...)

Thanks!
 

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The part number for the crystal is 300P04HN02. Can you let us know where you are located so we can suggest parts suppliers.

When you changed the battery did you reset the movement? This normally involves shorting the battery and a point on the movement marked AC.

Just to eliminate the mechanical side you should be able to operate the button contacts manually when looking at the movement. Sometimes the buttons can get clogged up or stuck and not make proper contact.
 

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Discussion Starter #3
Thank you very much! I live in Las Cruces, NM. The nearest big city is El Paso, TX - about an hour away.

I've shown my watch to a couple of jewelers in town, and the cheapest quote give to replace my watch crystal is $50, or $80 for a sapphire face. If I can order one online and replace it myself I would prefer to. The tutorials I've seen online on how to replace the crystal don't seem too hard with proper tools, and there's a local Harbor Freight that sells a watch press and dies.

I haven't tried resetting the movement, I'll give that a try once I get a chance to take it apart again.

Thanks!
 

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Discussion Starter #4
The thick plottens

OK, I had a chance to remove the movement and clean the bezel (which was only a decade or so overdue for some polishing.) I followed the directions for that to do after resetting the battery and found out that both buttons, in fact, work! Following the setting procedure made the stopwatch minute hand turn full circle and be set in minute increments. When I put the crown back in all the way and let the stopwatch run for a while, I noticed that the minute hand of the stopwatch was running even though the second hand wasn't. Neither of the alarm hands seem to be moving, either. So the problem isn't in the buttons after all!

...it's just in three hand mechanisms. Has anyone had a similar problem and can offer advice?
 

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The 7T32 and it's newer brother the 7T62 are both prone to coil failures. They have separate coils for separate operations. This means often you can have a watch that will keep good time but no chronograph function. Or you can have a watch that both of these functions work but you are unable to set the alarm dial or make the hands move at all on the alarm sub dial. This repair is not something a novice can repair and most watch repair shops will not fix because the labor time to replace the bad coil will typically exceed the value of the watch. These Quartz movements are of the type where either you work on them of you never touch them. They are not impossible to fix if you are familiar with them. There are just a lot of very small parts involved and it is extremely time consuming. If you feel confident on being able to swap a dial and hands you can look on eBay for a donor watch. Or you can buy a brand new substitute movement for the 7T62 which is part number YM62 for around $40 bucks from a watch supply warehouse. Several companies stock these movements.

Michael
 

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Discussion Starter #6
The coming of a new movement

Thanks for your help! Having played a bit with the watch last night, I feel fairly confident in taking the hands off and replacing the movement with a new one, in addition to replacing the watch crystal. It'll be an interesting introduction to amateur watch repair.

I found the model number specs for the crystal on this site and was looking through them. It looks like I need a round 30mm crystal made of Hardlex - is there any info on how thick the crystal should be? Can I order a generic crystal (or sapphire) face or does it need to match the model number exactly? (I'll order the movement number exactly.)
 

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I used a 1.5mm x 30mm generic mineral crystal from cousins on a 7T before and it was fine, just keep crystal square when pressing in so you don't deform the gasket
 

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Thanks for your help! Having played a bit with the watch last night, I feel fairly confident in taking the hands off and replacing the movement with a new one, in addition to replacing the watch crystal. It'll be an interesting introduction to amateur watch repair.

I found the model number specs for the crystal on this site and was looking through them. It looks like I need a round 30mm crystal made of Hardlex - is there any info on how thick the crystal should be? Can I order a generic crystal (or sapphire) face or does it need to match the model number exactly? (I'll order the movement number exactly.)
Swapping a dial and hands over to a good movement is a good way to start. There is a specific position the replacement movement must be in before you start the hand installation to ensure that the date change occurs at the correct time. If you have a good set of tweezers and some basic hand installation tools it is not to hard. If you have good steady hands that will make the job easier. The manual for the 7T62 is here on the site and you can download it. It will tell you how to set the movements and how to set the hands in place. The one thing that is not in the manual but is important is to keep you fingers off the dial face. once you get a fingerprint on the dial they can be a pain to clean and not damage.

Michael
 
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