Seiko 6138 - 12 hour hand runs when chrono stopped

[Khan]

Hi

When chrono stopped or reset, the stop lever to the left of the wheel is supposed to stop the teeth on the wheel. But it doesnt work - any idea why? It looks intakt. 

[Graziano]

Hi there, is the hour wheel stop lever on upside down and above the intermediate stop lever, it should actually be below it.

[Khan]

Hi 

The stop lever is below the intermediate lever and in level with 12 hr wheel teeth. 

[Graziano]

Hi, when the chronograph is stopped the hour recording wheel is braked by a stop lever and spring maybe the spring is bent or eccentric pin not in the correct position. You may have to remove calendar plate to further investigate Are you servicing this watch or just investigating the above problem? 

Hope this helps. 

Edited May 4, 2021 by Graziano

[Khan]

I was servicing it. Have done these movements before but I think you are right that the spring could be slightly bent.