So while working my expansion valve change I was looking at my windshield wiper motor and surveying what a pain it would be to work on and noticed the motor side of the mount bolts looked loose. Drilled two 1 1/2" holes on top side and cut out a strip to access motor and sure enough they both were two turns loose. I have no clue how they ever were tightened up in the first place. Just a FYI they are 10mm. A 3/8 will not work no matter how long you try. Took me ten minutes to figure that out. Lol.
Scott