Need help with link belt

I have an older link-belt excavator that was given to me by my father-n-law when he died. The machine has sat for the last 2 years, I got it home and ran it for a few hours and lost my swing (both directions) and left track. Both things came and went a few times before I finally was able to get it in a good location to park it. If I hold pressure on either swing function and slight pressure on the dipper, the track works fine, zero noise and zero power loss, let go of the joystick...

Need help with link belt

Need help with link belt