Noisy spindle bearings

[RSG]

I changed the oil last week in the headstock with an lube that I got from a local machine shop (don't know what exactly but they use it in their manual lathes) and didn't have enough to fill to the line so I found some 10 wt mineral oil and added that as well.

Now, when turning the chuck by hand I can hear the bearings roll over. It don't sound like they are grinding or anything bad but I just don't remember hearing them like that before. I'm probably just paranoid since I added 2 liters of the lighter oil that I am sensitive to the noise. The manual from the lathe manufacturer doesn't spec what oil to use so I called the other day and they told me EP 68. I bought some but have yet to change the oil.

Am I just being paranoid or do you think there is an issue with the bearings now that I added the lighter oil?

I'd appreciate any comments.

[John Evans]

Changing oil to lighter than spec'ed won't hurt the bearings. If a gear head lathe you might notice more gear noise. Put correct oil in it and turn up radio or turn off hearing aid!! LOL

[RSG]

Good to know!