I have a 2006 volvo160blc that i just recently purchased with 2600 hrs. The machine runs great for 1-4 hrs without any issues, then it starts whining, moaning, and looses power when you pull the arm back towards the cab when raking with the bucket (this is where is does it the most) and just about every other function in your left lever. The machine never looses power as in picking the machine up off the ground, it stays really strong there. You can kill the machine, come back in hour or so and it runs fine, then repeats the same process. Prior to this i changed all filters and fluid. Hydraulic fluid meets specs. I am using shell Tellus 46 which is the viscosity required for this machine. I have been told it could be a valve issue, all the way down to a small coil or solenoid issue. Haven't had a hydraulic overheating light come on or any high temp warnings. Any Advice would be greatly appreciated.
Good day strutter I suggest first check the button on the tank top you should hear air escaping when the machine has done a few cycles, (The air provides a pressure head for the fluid). Establish if the source of the noise is at the pumps. As a short term measure when you have warmed up and have the niose take out the suction filter in the tank and try again. Do you have any history of the machine - are the pumps original - the hours seem a little low for that age of machine. If you need any illustrations go the excatech.com web site you can find most of the information . Kind regards Uffex