This article is one in a series that have been released in conjunction with Wayne's book, 101 Projects for Your Porsche 911. The book contains 240 pages of full color projects detailing everything from performance mods to changing your brake pads. With more than 650+ full-color glossy photos accompanying extensive step-by-step procedures, this book is required reading in any Porsche 911 owner's collection. See The Official Book Website for more details.
Except for the early 1965-67 cars, the 911 windshield wipers have always been parked on the driver's side. Having the wipers on the left side can be annoying for many drivers who wish to maximize their visibility out of the windshield by reversing the parked position of the wipers.
The procedure for reversing the wipers is actually quite easy: the hardest part is gaining access to the wiper motor assembly in the front trunk. You need to remove the front blower motor cover, and then pull away the blower motor assembly. Make sure that you disconnect the blower motor hoses before pulling out the blower motor. The control cables that are connected to the motor and the air vents do not need to be disconnected.
The wiper motor is protected by a U-shaped bracket that is integrated into the wiper motor assembly. Before you start the disassembly of the wipers, make sure that the wiper motor is parked properly in its home position. It's wise to spray some water on the windshield and turn on the wipers (never run them dry, as this can scratch the windshield) just to see how the entire assembly works. Be careful of your hands, as this assembly is quite powerful, and could easily break some of your fingers if they are placed in the wrong spot at the wrong time.
The key to reversing the wipers is to park the wiper motor in its home position, remove the small arm that is attached to the wiper mechanism, rotate the wipers to the right side, and reattach the arm. It is also just as easy to switch back if you are restoring the original factory location that a previous owner of your car had moved.
Make sure that you test the wipers before you replace the blower motor assembly and hoses. If you are having problems with the intermittent wiper function, then the relay is a prime candidate for cleaning or replacement. The wiper motor relay should be located near the wiper motor in the front trunk. Location varied a bit from year to year, but most of the later cars had the relay attached to the firewall. Try removing the relay and cleaning the contacts. If that doesn't work, then it's probably time for a new relay.
When reinstalling the blower motor assembly, be very careful to make sure that no cables, wires, or hoses get in the path of the wiper motor assembly. On some of the early cars, if the wiper motor gets stuck, the resulting current overload can burn out the wiper switch.
With the wipers parked on the right side, the straight wiper on the left sticks up into the area of the windshield. For a cleaner looking windshield, swap the left and right wiper arms. Then, take the bent wiper arm, place it in a vise, heat it up with a torch, and bend it slightly in the opposite direction. An alternative is to replace the angled wiper with another good used straight one.
While you have the blower motor out and accessible, make sure that you inspect your hoses. Old OEM hoses can become brittle and crack with age, and it is a wise idea to replace them while you have access to them. It's also a wise idea to inspect your master cylinder and the surrounding area. If you see brake fluid leaking from around this general area, it's probably time for some replacement or repair work on either the master cylinder, the brake booster (for cars with power brakes), or the reservoir feeding system. See Project 52 for more details.
After removing the carpet and the access panel in the rear of the front trunk, disconnect the blower hoses from the blower motor and front air vents. Pull out the blower motor so that you can gain access to the wiper arm assembly underneath the dashboard.
Locate the small arm that rotates and drives the wiper arm assembly, hidden behind the U-shaped protective bracket. Remove the nut (shown by yellow arrow) and pry the lever arm off of the shaft that is connected to the wiper motor. Rotate the wiper arms so that they are all the way on the right side of the windshield. The motor shaft should not turn at all while the wipers are being moved. When they are parked all the way on the other side, reconnect the arm and tighten the nut on the shaft. Spray some water on the windshield, then flip on the wiper motors (spray some water on the windshield first), and test to make sure that they are working properly.