Curious if it makes a difference how the 4 bolts that mount the engine to the frame are configured. The parts manual for the 16hp mounted to 4016 shows the bolts down through frame with lock nut on bottom. Mine is mounted the opposite with lock nuts on top and bolt pushed up through frame.
I does not seem to have caused any problems, but still just wondering.
Sometimes, it is extremely difficult if not impossible to insert the bolt from the top because parts of the the engine block obstruct the area directly above the motor mount foot. This tends to be more likely when there has been some sort of re-power.
Inserting from the bottom with the nut on the top is the only recourse in these cases. Using a new lock nut (nylock / distorted thread / elliptical offset) will prevent loss of the nut and bolt due to vibration.
My 4020, and my 4118, have the back bolts welded into the frame with the bolts pointed upward, nuts on top with lock washers. All of my Case tractors always had the bolts pointed upward, front and back.
We did get our storage shed full before the snow hit us. Sorry but it is so hard to get a good picture. This is a 50x80 building. So the question is, how many garden tractors can you count? some are...