never been around a excavator before and have ran it a couple days now and after running a full day i noticed this i ran it for my 2nd full day today and it didn't seem to be as bad but it was still there the machine has set for 4 months before i purchased it. is this anything to worry about.
there should be an access plate or two that you can un bolt and get a peek inside the turntable, you shouldn't have water inside there... once winter sets in and it freezes it can do very bad things! what kind of machine is it? the boot/rubber cover on the rotary manifold may be cracked/torn letting rainwater in or could be loose bolts on an access plate...
Deere 270LC I'll look for that access panel and check the boot on the rotary manifold it dont seem to affect operation
I'm with Ronsii, Need to climb up under that machine and loosen the access plate and let the water out, fix the swivel boot, check the fill access hole on top for a bad gasket/ loose bolts. You will more than likely need to change that grease out, Kind of messy job. Most have a grease cavity that holds up to 5+ gallons of grease. The swing gear from your swing box lies in about 1/4 inch of that grease and is pulled up between the swing gear and turntable gear to lube it. I would also grease the bearing a little more often until you get it straightened out. It takes some work to clean that cavity out.
Make sure the area on top is clean. There are slots around where the lift cylinders attach that need to be open, so that rain water can drain out.