The photo shows a top view without the top frame mounted. Do not remove the top. It will be easiest to access the belt by removing both sections of the plastic enclosure.
The orange arrow indicates where the motor hinges.
The two yellow arrows indicate the nuts that are used to adjust the motor in the direction of the arrows to tighten the belt. There is an upper and lower set of nuts that need to be adjusted equally. The nuts on the outside of the plate need to be unthreaded toward
the end of each threaded rod so that the plate has room to move in that direction away from the large pulley. The nut on the inside of the plate can be unthreaded out in the same direction to push the motor out creating more tension on the belt.
Once the belt tension is satisfactory the nuts on the outside of the plate can be tightened against the plate to lock the nuts at this location.
