Need advise or opinion why ST BB3X vibration goes high after Major Inspection.

My Plant is using GE 9FA single shaft machine. after recommendation from GE, we had change our bearing tilting pad from 4 pads to 6 pads, but then vibration reading (ST HP turbine) is on high side for BB3X. Any one got similar situation after changing the tilting pads? Lube oil temp is maintain approx. 50'C.

 

We did the opposite and sub-Synch vibration went drastically down. I don´t understand why they went from a 4 pad bearing to a 6 pad bearing. We went the opposite way on nr 3 bearing.Actually there is a TIL, TIL number 1583, please take a look at that TIL.

 

Thank you for the reply, I'll have a look into that TIL 1583.