John Deere 870 engine/ transmission sound

[Freedom.acres]

When seated on the tractor, to the left side a hydraulic cylinder to the front axle pitman arm would be there for power steering.

Listening to the noise in the YT vid, it's constant and does wind up and down with RPMs. I would assume it's a bearing.

Ok I have confirmed there is power steering and the sound is coming from the housing where power steering hydraulic lines originate. I ran the tractor yesterday for about 3 hours and never made a peep. But this morning started it up and it hummed a little bit but stopped.

 

[Freedom.acres]

I believe the source of sound is in this valve somewhere should I pro actively disassemble and inspect if so what should I look for. Or where it is intermittent do I wait for the problem to get worse so I can more easily diagnose.

 

[bmaverick]

I believe the source of sound is in this valve somewhere should I pro actively disassemble and inspect if so what should I look for. Or where it is intermittent do I wait for the problem to get worse so I can more easily diagnose.

It will get worse, to the point you have no steering. A parts manual would be ideal to reference for the diagrams where it's on the machine. Typical Yanmar arrangement is near the bottom of the steering column.