Over the past year, I have noticed that my windshield wipers were working harder and clearing less water on my 1986 Spider. The wipers dragged and stuttered across the windshield with every sweep of the blades. It got to the point that it had to be raining quite hard for me to turn them on, they were so irritating. I replaced the blades and the symptoms disappeared, but they soon returned. I finally decided that I needed to look under the hood, as it were, to see what was going on.
First, I removed the wiper arms from the wiper arm pins. Then I removed the bright stainless steel trim strip at the base of the windshield that is attached with a screw at either end. To remove the air grate, I opened the hood, removed the four screws that hold the grate in place, removed the rubber seal between the grate and the car, and pulled the grate towards the front of the car to release it from the clips. The screws fasten to small, square cone shaped plastic "nuts" which I held with a box-end wrench while removing the screws. Don't pull the air grate too far away from the car because the tubing to the windshield washer is attached to the air grate.
Now, you have access to the wiper motor and the wiper mechanism. I originally thought the wiper motor was operating at less than optimum due to dirt and grime and needed to be cleaned. I removed it (three bolts secure it to its bracket and one nut secures the wiper mechanism to the motor) and unplugged the electrical connector. I discovered that the motor is a sealed unit and there isn't any way to easily clean it. I looked at the electrical connector and found it to be free of corrosion. Then I tested the wiper mechanism for ease of movement. I found it quite stiff, so I removed it to inspect it better -- just remove the nut on each of the wiper arm pins that holds the pin to the body of the car.
I tested each of the three ball joints and found each to be stiffer than I thought they should be. Each ball joint bas a rubber seal, much like a suspension ball joint. I pried back the seal on a ball joint and discovered bits of dried grease and a dry, shiny ball. I used two small screw drivers to coax the seal off the joint and out of the way and removed the dried grease, sprayed on some Liquid Wrench and exercised it to work the liquid into the joint. I experimented first with some multi-purpose grease (Castrol) but found that it made the joint too stiff. I settled for white lithium grease which worked much better. I replaced the seal and filled it with more white lithium grease. I repeated this for the two remaining joints.
The wiper arm pins were inspected next. The inside shaft turns inside the wiper arm pin housing with the wiper arm attaching to the inside shaft. The wiper arm pin housing is held on the shaft by a round clip that fits into a groove at the top of the shaft. I found the shaft to have a slight coating of rust and road dirt, but otherwise to be in good condition. I cleaned the loose rust and debris from inside the housing, coated the shaft and the inside of the housing with multi-purpose grease and reassembled the pin.
Reassembling all the other parts is the reverse of how they were taken off. When you put the wiper mechanism on, make sure that it works correctly, for there are two ways that it can fit. The two wiper mechanism arms need to be on the same side in relation to the right side wiper arm pin. A nice touch is that the shaft on the wiper motor is indexed to the hole on the wiper mechanism so that it only goes on one way.
To help install the air grate, cut a thick metal coat hanger into eleven two-inch sections and bend each section into an "L" or hockey stick shape. Place an "L" between the prongs of each attaching clip (the prongs of the clips are difficult to separate during installation and the "L" pieces do that for you). Install the panel with two prongs above and one prong below the grate (the upper prongs also hold the stainless trim strip in place). When the grate is properly positioned with respect to the clips, pull out the "L" pieces and push the grate into place. Next fit the trim strip. Carefully lay the strip on top of the grate and gently coax it under the clips on the driver's side until the first screw can be inserted. Tighten this screw enough to allow the trim piece to pivot, then carefully press down and back on the trim strip to engage the remainder of the clips (WD-40 may help). Finish by placing a small wood block on a piece of cloth on the grate and carefully striking the block with a rubber mallet to seat the trim strip, working from the driver's side. Tighten both trim screws. Next, insert the rubber seal, adjust the grate's alignment if necessary, and install the four mounting screws.
The first test was in a light rain when the wipers had acted the worst and they performed flawlessly; no stuttering, jerking, or straining. A windshield wiper tune up might be just what your Spider needs for the coming spring showers.