Cant quite make out from your pictures how your mounting is, but if the subsoiler is pulling out of the ground I'd think you dont have the a frame quite upright. It should be set 90 degrees to the ground, so the tine is pulling itself in and only the tractor hydraulics prevent it going right down. To use it for pipe laying you need an attachment that you attach to the bottom of the tine and then connect the pipe to this. As you pull through the ground the pipe folows the tine and when you get to where you want to go you disconnect it. Hope this helps?