Longines 430 Advice Needed

[margolisd]

Hi all. I'm servicing a Longines 430 movement and have a couple of questions. First, I'm having trouble tracking down a replacement main spring. The barrel had DO NOT OPEN printed on it so it looks as if you have to buy the barrel with the mainspring already fitted. Cousins is showing this as obsolete. There is one on eBay for around £90 in Australia but that's about all I can find. I did, of course, open the barrel and it seems pretty normal so I'm not sure why they don't like you opening it up. It's a T end spring. I measure it to be 1mm wide, 0.1 thick, 350mm long and the barrel is 10.5 inside diameter. I can't seem to locate anything like this. Any ideas?

Also, I've been reading up on this movement. It's super fast 36k beat. I read that it was quite revolutionary in the late 60s and that advances had to be made in lubrication in order to make it work. I presume my Moebius9010 will be okay on the high speed parts? 

[Jon]

http://www.obsoletewatchandclockparts.com/

This guy is called John Senior and I get some parts off him, including mainsprings. He may not have that T end listed, but drop him an email. He's helped me out in the past. That's a lot of money for a spring from Oz, but the lack of them drives the price up

[Nucejoe]

What is wrong with the spring?

[margolisd]

Sorry, I missed your responses. Thanks for the tip on John Senior. I'll give him a try! As for the oiling of the super fast escapement, it's an interesting issue. The service manual says rather than oiling you should replace the escape wheel which is coated in some kind of dry lubricant. Now obsolete nearly 50 years later. But I've read that other repairers have had luck using Fixodrop and a tiny amount of 9415 on the exit stone so I'll give that a try.

On 9/16/2018 at 6:36 AM, Nucejoe said:

What is wrong with the spring?

It's old and a tad kinked. Time to replace