This new to us machine has yet to dig a thing until we can fix enough stuff on it to even do testing. It was running and working when bought but some people's expectations of "runs great" are very low. Anyway, one of the only unusual noises I hear from the machine come from the pump drive area. Does not "seem" to be coming from the main pumps. Noise is a rattly vibrating sound. As mentioned before, hydro fluid needs to come out and we will do that before it does any work. Fluid does have water in it fo sho. Noise seems to be coming from the drive or coupler area but I was not sure if there just some noises these old birds made? I did drain the fluid (1gal, low) and did not get any chucks of steel but did find a friggin small rock!:Banghead Bright ones they were. Because this drive is a SERIOUS PITA to pull and rebuild if it was determined to have issues, I am tempted to run it and see what happens. Is there any way to check condition of the drive or coupler? will a bad drive take a pump with it? I will probably get some video of it running for more help but I would not consider this a whine or a gravely (bad bearing) sound. It seems more like something loose. The pumps vibrate a bit when running and not sure if they should operate like glass.
Typically speaking, when the drive coupler goes down you'll notice it when you shut the engine down. As it comes to a stop it will make a clunk clunk clunk sound. If the machine uses a split gearbox to drive two pumps, problem could be in there as well.
Well, it seems the pump drive was missing about half the bolts mounting it to the engine and some existing bolts were loose. As well, we found both main pumps to be slightly loose and could move them by lifting up on them. There is still some vibration when touching the pumps but seems pretty normal and 95% of any odd noise in that area is gone. I hope the loose drive did not damage anything permanently. I originally thought the drive was the rear engine mount but that is not the case so all that weight from the pumps and drive hangs off the end of the engine. Poor design IMO. Pumps should have aux support bracket. We drained the pump drive and found no shrapnel but found a friggin rock! Some people care so much... We replaced the oil, tightened everything up, and moving on to the next thing on the list...