[WireNut]

 My Pioneer PL-117D table hums. It has a new belt, lube job, new Stanton D-61 stylus with an older Stanton 600 series cartridge installed. What could be causing the low level hum?  It's a nice table and I hate to scrap it out. Right now it's setting Ideal.

[tomytoons]

Check the cartridge tags.
Lose ground? That is what it seems like.
Check the RCA ends.

[WireNut]

Check the cartridge tags.
Lose ground? That is what it seems like.
Check the RCA ends.

I removed the original cart from the stock headshell and cleaned the connectors and then installed a pre-owned Stanton 600 series cart with a new stanton D-61 stylus, gave it a good lube job and new belt, but it still has a low level hum/rumble. I hate to scrap it out, but the low level hum/rumble keeps it sitting Ideal on the floor.

[WireNut]

I'm wondering if the low level hum maybe due to an unshielded motor.

[neobop]

I'm wondering if the low level hum maybe due to an unshielded motor.

Not likely.  Did you have this table going before without hum, or is it a new table? 
What I'm getting at is about the cart that was on there before the Stanton, was there hum with that cart, or don't you know?

Most likely candidate is the old Stanton.  If that's not the cause of the problem it's probably the arm wiring or ground wire.
neo

[Mark Korda]

Hi Wirenut, Neobop mentioned the ground wire. My Technics SL-20 which is as old as your Pioneer has a ground wire thats attached right beside the RCA jacks. My turntable will  hum unless I have that grounded....Mark Korda.