The coolant does not EVER touch bearings, period. The sealed bearing is just that, sealed. It has its own grease and is sealed on both ends to prevent outside contaminant such as coolant, dirt, etc from entering. When a water pump starts weeping out the weep hole that means the water has made it passed the seals and making out to the weep hole, and possibly "washing" away the grease. Coolant will act as a heat sink to pull heat from the bearings through conduction. Over tightening of the pump belt will put more load on the bearings and generate more heat. You will be surprised how long you can operate a part on a sealed bearing with no cooling means.
Coolant is NOT a lubricant for metal parts or rotating parts.
Coolant is NOT a lubricant for metal parts or rotating parts.
Last edited by NissanEgg
on 2014-12-19
at 13-50-36.