Hi guys I recently purchased a new to me 2002 Bobcat S185 from an estate. Very well looked after and only 786 hours on it. The other week I noticed a very high pitched screeching coming from the right side & the right side did seem to be down on power. I have noticed running straight I have to keep correcting the right side. I pulled the case drains on the weekend and did find some very small bits of metal in the right filter. Chain case was also a little over full. No other leaks found on the machine. I did block it up and run it, and the screech/whine is much less noticeable when not under the weight of the machine. Does anyone have any thoughts on where my focus should be next? Drive motor, final drive? Any help would be greatly appreciated. Thanks.
Kinda sounds like your going to need a drive motor on the right side at the least. Metallic particulate matter has probably clogged a filter as hydraulic "screech" as you refer is usually high pressure fluid going over the relief valve from the pump. Something is probably deadheading the pump output sending the fluid over the relief valve setting and it's probably the operating motor for the affected side.
Kep an eye on the oil level in the chain case. If it was overfilled slightly, and you've drained it back to proper level. If after you've ran it for a good while and the chain case oil level goes up again then you've got a faulty drive motor. When those motors go south they produce more case drain than the case drain line and filter can handle, which puts pressure on the shaft seal into the chain case, blows out that seal and fills the chain case with oil.
Thanks for the information. I will be sure to keep an eye on the chain case level. I figured the drive motor was getting weak before I got this screech. Is it common to find small pieces of metal in the drain filter when a drive motor goes south?
Small amounts of metal in case drain filter indicate a problem. When a motor goes south, full grenade, it fills the filter with metal. You may be in the very early stage of motor going bad indicated by debris in case drain filter, and will confirm if that chain case keeps filling with fluid.
Are these older drive motors worth cracking open for possible repairs, or just looking for a reman if available?
I never tried rebuilding those motors, typically because by the time you notice a problem they're pretty knackered up inside. Those motors can be expensive and it's been years since I've purchased one, but I've got a number of them from loader parts source. https://loaderpartssource.com/
I will check them out and see what they have for availability. Appreciate the info