Longines Automatic Watch For Servicing

Before servicing

After servicing

This Longines watch model: L4.721.2 was sent in for servicing because of bad timekeeping. Looking at the timegrapher's reading before servicing shows that the watch is running slow at 201 seconds per day. The amplitude is only 159 degrees  and beat error is 8.2 milliseconds. After overhaul and oiling, the timegrapher's reading improved drastically. The accuracy is +1s/d, amplitude back to normal at 269° with no beat error.

Movement caliber: ETA2892-A2 Automatic, swing frequency 28800 times/hour, lift angle 51°