Longines cal. 19* barrel help

[JohnC]

Hi all,

I am servicing a Longines 19A automatic. I ordered a mainspring from Cousins, but in the washer it is actually wider than the barrel inner diameter. I think I may have the wrong barrel - the inner diameter of the washer is 8mm, and the barrel inner diameter is 7.4mm. Does someone have a 19A or similar caliber (AS, AD, ASD) near to hand, and can they measure the inner barrel diameter for me? Thanks.

[mikepilk]

The Cousins size agrees with the GR database which lists the diameter as 8mm. Surely the wrong barrel wouldn't work ? Very strange

 

[JohnC]

@mikepilk
yeah it's so weird. The watch was running, and the train runs beautifully if I reassemble with an empty barrel. Original mainspring is the correct height and thickness, but yeah, the new one is too wide in the washer to just slide in. Suspicious and vexing! 

[rodabod]

They are not always fitted inside a washer which is smaller than the barrel inner diameter.

[JohnC]

@rodabod
okay good to know, thanks. That's a bit annoying of them, frankly.

[rodabod]

Is there a single-digit number stamped on the ring? Maybe "8"?

[nickelsilver]

In the 1974 Generale Ressorts  book they list the 3196-X for this caliber, and state the ring diameter as 8. Like Rodabod said, they aren't always perfect for every caliber.

[JohnC]

Yes, stamped as 8. Mainspring code is 3196X on packaging.

[mikepilk]

I've had several instances where I've had the "correct" spring as recommended by Cousins and GR, and the washer has been too big. Just one of those annoyances.

[JohnC]

Ehhhh yeah ok, sounds like that's the case here. Thanks guys