Wiper motor or linkage?

[nurflugel9]

I have a 1984 Pininfarina Azzurra and the wipers stopped working. I disconnected the motor from the linkage and it turns in the three positions, but doesn't turn when connected to the wiper linkage. The linkage is a little stiff even after I cleaned and sprayed some silicone lubricant on it. I am trying to understand how to judge the resistance of the linkage or the power of the motor to decide which one to replace. Any help would be appreciated.

[spider2081]

I am trying to understand how to judge the resistance of the linkage

First remove the short linkage that connects the motor to the passenger side, then remove the long linkage that connects the passenger side to the driver side. The remaining short pieces with the linkage pins on them should move totally free. Little if any effort to rotate them. If one side is stiffer (requires more effort to rotate) than the other that is an issue,
I drill the pot metal outer casting with an 1/8 inch drill for lubricating the shaft inside the casting. Then once a year I remove the chrome nut and black dress cover and lubricate the shafts with engine oil. I drill the hole at the bottom of the chrome nuts threads so it is facing up when installed in the car for easy future access.

[spidernut]

99.9% of the time, the problem is with the wiper arm mechanism - specifically the two shafts that stick through the cowling where the wiper arms connect. Those shafts do NOT contain any kind of bearing, so the internal lubrication dries up making them very hard to rotate.

In the past, I have used two successful methods of lubricating the wiper arm shafts.
- Remove the wiper arm assembly from the cowling before attempting this
- Obtain a grease needle fitting (like one used to fill a basketball with air but for a grease gun)
- Measure the diameter of the tip of the grease needle fitting and locate a drill of the same diameter
- Drill a hole using that drill bit at the top of the wiper arm shaft casing (the solid shaft is inside the casing). The hold only needs to penetrate the outer casing of the wiper shaft which is about 1/8" thick. (if your wipers shafts are completely frozen, you can drill a second hole at the bottom which I'll explain later)
- Inject grease into the top hole that you drilled. You'll have to force the grease into the wiper shaft using a grease gun and rotate the wiper shafts to distribute the grease. If the wiper shafts are really frozen up, you can spray a rust penetrant into a top hole and as you rotate the wiper arms, the penetrant will come out through the bottom (usually with a LOT of rusty coloration). It can then also be followed by injecting grease into the top hole until it comes out the bottom.
- You can then clean the wiper arm shafts and plug the hole (or holes) with a small allen screw or a very small dab of silicone.

You'll be amazed at how well your wipers will work once grease is injected in the wiper arm shafts. Just make sure that you don't drill too deep and inject enough grease while rotating the wiper arms to loosen any rust.

[nurflugel9]

Thank you for the advice. I will try that.