Hello - I have a JCUT Router (chinese). After less than 200 hours my 4.5kw water cooled spindle (single phase, 220v ) wore out the bearings. There are a few factors that could have contributed including the quality of the spindle itself. On several occasions the water was not running and the spindle got quite hot, the application I use the machine for is pretty arduous (material removal with a long extension) and I don't have a dust extraction system. You will see in pics. I am relatively new to machining and so I just don't know what to focus on so that I can get better tool durability in the future. finally, i was told that this spindle should have a bearing ring to reduce wear caused by electrical "surges"? does that make sense and is it is a significant consideration?
Attachment 248630 this is the spindle with extension and 1.25 inch cutter.
general questions about re-assembly and bearing "tightness"

Any help would make a huge difference. Thanks in advance!