Malcolm,
Turn it off disconnect the
battery cable and unplug the 110ac.
Then take the cover off of it. It sounds like the cooling fan is bad or something is loose. You may be able to see the problem once the cover is off. You may have to remove the
fiberglass seat enclosure to get to everything.
After you get it apart and check it, you may have to hook things back up to identify the problem.
Good Luck