mainspring problems i think

Happy new year to one and all ,

I recently took a wee punt on a watch of eBay a Seamaster 145.029 (movement 861 )the problem's arises when i wind the watch i get to about 10 turns off the crown and i hear a click the watch never gets fully wound up every 10 turns i keep hearing this click i would say the watch runs for around 12-15hrs before it stops . my intention is to have it service.
i'm just queries if anyone can shed some light on this for me.

photo of the watch is attached ..

thanks in advance

steve

thanks that was my thought as well . this should be fixed under a service 😀.