dane6895
New member
I have aJD 750 with hydraulic controls mounted on th tractor. I had a four angle plow on it thatworked fine. I bought a model 67 loader off a working machine. After installing it, I have a nasty whine when lifting the loader. I tried swapping the lines, and it follows the line to the other control. I serviced and cleaned the filter, etc. It wont pick up a load either. I found a worn cup on the relief valve that would explain no lift. But why the whine? Do I need to flush the lines on the loader? Or would a bad cylinder cause this? One does have a small leak. The three point hydraulic works with no noise. I changes out the quick disconnects on it as well. Im at aloss. Can someone give me some knowledge? 
