Overheating in Bearings often is the result of overfilling the bearing or too frequent greasing intervals. Seals usually get damaged due to overfilling. Sometimes bearings also get overheated due lack of grease supply. To overcome all these issues Add a small amount of grease and monitor the temperature change. Also, try to Decrease greasing frequency.If the grease starvation is occurring try to know the reasons and also try softer grease.