Water contamination on lubricant

Double suction centrifugal pump running at 1000 rpm with oil bath lubrication reported has noisy outboard bearing. Vibration data taken and shows an increase noise floor (figure 1).
It was also found a leak on gland packing that cause water spray out toward bearing casing. Increasing noise floor was suspected caused by improper lubrication, this was caused by water get into the bearing.
Recommendation was made to drain oil and inspect if the water has enter the bearing.

Figure 1. Vibration spectrum after water contamination

The suspicion that water has entered the bearing was true. They found some amount of water on the drained oil.
After flush bearing housing and change the oil, the pump was put back in service and noise floor was decreased. Vibration spectrum after and before oil replacement are shown in figure 2 .

Figure 2. Vibration spectrum after oil replacement