I have owned this machine for a couple of weeks and noticed this issue shortly after getting her home. The drift in the boom is intermittent and occurs while the machine is running, both when the machine is cold or hot. It may happen twice in 2 hours of use. I have attached a video so you all can see for yourselves and provide any insight into the cause. The issue usually lasts for a minute or so and then corrects itself. I am a novice when it comes to hydraulics and I appreciate any input or troubleshooting ideas you may have. https://youtu.be/S85bxovqRWg If you get tired of watching the boom drop, fast forward to 1:45 in the video and you'll see the situation go away and return to normal operation.
When it drifts down, will it hold the back of the tractor up if you were to put down pressure and then release the lever?
I haven't tried to do that yet. I will certainly check next time I operate it.