Here we have a lovely vintage JLC Powermatic, as i understand it the Powermatics were one of the first “Bumper ” movements (automatic’s) with a power reserve. The bumper movement was a early attempt of automatic winding, however the rotor did not rotate a full 360 degrees but a smaller amount with the help of springs to keep it moving, this was obvious a more in efficient way way of winding the watch however it had a very satisfying “bump” when worn.
The power reserve indicator would alert the user to how much power the watch had stored (in hours) until the watch would stop working.
Hidden inside the watch is a very lovely Caliber 481. … the build quality is superb and wonderfully decorated as one would expect from the luxury watchmaker.
The watch was in great condition for its age, however the timing was all over the place, the watch hadn’t been serviced for over 40 years!
on to the disassembly…
After the watch was fully disassembled, the watch parts were put in the parts cleaner and a replacement mainspring was ordered. After the cleaning cycle, the watch was then reassembled, lubricated and calibrated.
The strap was replaced witch a bland leather band, overall very happy with the outcome,