Service: Longinges Ultra-Chron calibre 341

IMG_0094

The Ultra-Chron were fitted with calibre 340 and was Longines entry to the High beat race of the late 1960’s.  This watch is fitted with a 341 that also features a date mechanism. The serial number says this watch is from 1968. It’s in very good condition, but is not running. I’m suspecting that the mainspring is broken.

IMG_0095

Movement is a bit dirty, but very nice.

IMG_0096

The 340 series have nice movements, but I don’t see the need of a loose oscillating weight washed and bush.

IMG_0097

I remove the autowinder mechanism.

IMG_0099

Here you can see the inside of the autowinder mechanism.

IMG_0098

The movement without the autowinder mechanism.

IMG_0101

Movement out of the case and I’m about to remove the hands and dial.

IMG_0102

Dial and hands removed and you can see the date mechanism. Nice construction that has a very snappy date change.

IMG_0103

Date mechanism cover plate removed revealing more of the date mechanism.

IMG_0105

I start taking the base movement apart.

IMG_0109

Here you can see the gear train layout.

IMG_0111

Movement almost taken apart.

IMG_0112

Hmm is that an invitation to open the barrel?

IMG_0113

As suspected the mainspring is broken.

P1030503

All the parts cleaned and ready to be put back together.

P1030504

The cap jewels are tiny.

P1030506

I fit a mainspring that is close to the original: 0.95 x .15 x 340 x 11.2

P1030507

Movement looks so much nicer when clean.

P1030510

I put the setting/ winding mechanism back in place.

P1030511

I put the autowinder mechanism back together.

P1030512

Date mechanism back together.

P1030513

Movement back in the case looking very nice!

P1030686

The mainspring was spot on and I’m happy with the performance of the 36.000 beat pr hour movement. 

P1030514

I now fit the oscillating weight.

P1030517

Watch in fantastic original condition.

P1030535

The 37mm case is almost too large for my wrist, but still feels very nice.

This entry was posted in Uncategorized. Bookmark the permalink.

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s