AR ES–1 Problem.... Suggestions

I have an AR ES–1 turntable that has been in storage for a while. I have set it up and now hear a soft rubbing–grinding coming from the bearing, I believe. I have removed the inner platter and gently swabed the bearing and bearing spindle and relubricated same. This has made no difference.Does this mean the bearing is bad or the bearing seat or what? I realize this isn't a high end unit but when it was new I replaced the horrible stock arm with a Sumiko Premier MMT and a Sure V15 5 MR cartridge that is still pretty low mileage. I would rather try to remedy the problem than upgrade at this time. Does anyone have any experience with this problem?? Any ideas??Thanks
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Above are all very good tests. You may also contact Underground sound in Memphis TN. They are old time AR tweekers and offer info, repair, parts ect.

Very helpful post Viridian. Sean
Mr. Merrill has retired a short while ago and I don't know if you can now get a whole lot from Underground Sound for AR tts. It may be worth a try, but don't hold your breath. Plenty of info available at AA on the mother of all suspended tts. A number of companies have replacement motors. I believe the original was manufactured by Hurst (won't swear to that though) and they are still available from them. Good luck and don't ditch that cd player!
I did some trouble shooting before posting and did the things that Viridian suggests. The brushing–grinding is in the bearing, seat area. There is another problem though which is motor related. Even while the unit is off the motor trembles-vibrates(to the touch). When on the platter turns at the right speed but the vibration while off troubles me even though I don't know weather it adds rumble during play.Thanks for all your help and any more suggestions for a remedy or as to whom to contact for information would be appreciated. Cheers
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Yes, they do that. Quite strange that the motor continues to vibrate even though the tt is off, but that is normal as some current always runs to the motor; weird, but normal.
The spindle is square and true with no wear or damage I can see.The platter doesn't seem to be spinning as free and easy as it should and the very low grade brushing–rubbing–grinding sound is ever present. I believe I will try to contact the sources suggested above for assistence. The trouble "looks" to be the bearing seat,(the brass or bronze alloy?) that the bearing rests on. Thanks Viridian and all others for your input. Peace