If any of you have ever removed your windshield wiper motor you know that it is very difficult to access the nuts located on the inside of the firewall that secure the four screws that are inserted through the wiper mounting grommets. I had no issue removing the nut securing the wiper linkage to the motor shaft by accessing it through the center console. I won’t comment on accessibility for those having the A/C unit located in the console. I unscrewed the four 10-32 round head machine screws holding the motor assy. in place from the outside; letting the nuts just fall into the car’s interior to be found with a mag pick up tool. Getting to them from the inside for reinstalling again - even without A/C - was too painful to think about. So I offer this solution which makes installation whenever the motor is removed, quick and easy.
Having worked in the machine design world for many years, I often used “PEM Nuts” when sheet metal parts needed to be secured with threaded fasteners. Penn Engineering (http://www.pemnet.com/) offers an entire array of fastener solutions so I turned to them for my way around this difficult problem. I chose two different types to evaluate. One a female 10-32 mount (P/N VM30SS-032-2Z1) and the other a 10-32 x 3/4” (5/8” stud length) style mount (VM30FH-032-12Z1). The company was nice enough to send me samples of both at no charge. Complete CAD drawings can be found on their website.
Because the four holes in the fire wall are a tight clearance fit for the 10-32 screws that hold the motor mounting plate and rubber grommets I was concerned about using the female mounting, as I would have to open the holes in the firewall and was concerned about losing alignment with the motor bracket. So, I went with the male 10-32 stud mount which required no modifications to the car. The mounting method is designed to be secured with an adhesive and I chose a two part epoxy putty since it wouldn’t be dripping down my arms while I inserted the fastener into position through the large opening in the firewall with my fortunately long fingers.
After inserting the fastner thru the hole in the firewall, I installed a flat washer and a nut then pulled the fastener into place forcing the putty to “ooze” into the holes in the backing plate making a secure bond to the fiberglass body. Once cured, the wiper motor with its base plate could be dropped onto the studs & flat washer, and secured from the outside with another flat, a lock washer, and 10-32 hex nuts.
The purists among you may like the female -2Z1 style fastener since it can be secured using round head machine screws like the factory used. Either way, there is no need to go at it from the inside again. Those of you with A/C, my apologies, as I don’t know what you have for access to the nut securing the shaft to the wiper linkage but the motor securing method I have described should work for you just as well.