Mainspring Dilemma

[Bill1]

Hi to all,

I have an old citizen 8270A and I would like to source a new mainspring. From the information I have found online, the main spring has been discontinued.

The dimensions (from online source) :  1.45 x 0.11 x 380 x 10.5.

From the Cousins website I have found what I believe are two options. I am unsure which one is suitable (if at all)

# 1. 1.45 x 0.11 x 360 x 10.5 (shorter length)

# 2. 1.45 x 0.11 x 380 x 10.0 (smaller barrel diameter).

Any advice would be welcome.

 

 

[tomh207]

Hey Bill, the second one matches closest, the barrel diameter is more about what this spring will easily pop into, not about any other parameter. You could have a 12mm barrel that uses that same spring and this one will fit just fine.

 

Tom

[Bill1]

Hi Tom,

Thanks for the quick reply. it is appreciated.

 

Bill.

[AndyGSi]

Can I ask where you got the information as the 1.45 seems a little large to me.

[Bill1]

Andy,

Thanks for your reply - you are correct, my information is wrong.

I went down a rabbit hole last night looking for mainsprings for citizen, AS & seiko. I believe I quoted the dimensions for the AS movement.

looks like I am back to square one for now. 

Any way thanks again - 

 

Bill.

[AndyGSi]

Where in the world are you?

Have you not got the old spring to measure?

From the Service Manual I'd presume the 8260A & 8270A would take the same spring.

https://www.ebay.com/itm/275155274976?hash=item4010884ce0:g:QRwAAOSw29Nh~rQT