This is planned to be a straight forward clean / replace / repair as necessary.  I'm planning one upgrade: installation of pulse wipers.  My car came without them and I hate the sound of wipers bouncing across a dry windshield.  The wipers operated in a jerky motion that I'm hoping will be fixed by cleaning and greasing the motor and transmission.

PULSE WIPERS:  After some research, I discovered that upgrade to pulse wipers requires a different motor assembly cover, pulse wiper module, wiper switch, and some additional wiring.  The assembly cover is not, to my knowledge, available from a vendor.  I sourced mine from a salvage yard in Illinois.  I found an example on line and sent them the picture.  It was a little spendy (about $50), but well worth not having to listen to wipers rubbing across a dry windshield.

The OEM modules also cannot be purchased from the vendors.  For some reason, these are insanely expensive at around $200 for one that's in good shape.  The good news it that a non-OEM replacement module can be had from the vendors for about $50.  The description says these are direct replacements for the OEM modules.  The switch is available.

Modifications:  None.

Upgrades:  One

  • ​Installation of Pulse Wipers

​​Wiper Transmission

Since I've owned the car, I've never liked the wiper performance.  During operation, the wiper blades would jerk across the windshield instead of glide.  I attributed this to either a worn out wiper transmission or wiper motor.  I started with the transmission.

The transmission connections were solid and moved easily.  I disassembled the transmission as far as I could and cleaned everything.  After painting, I lubricated the copper bearings and reassembled.  The ends of the transmission are sealed bearings, so no powder coating is possible. 

​​Wiper Motor Rebuild

After cleaning the wiper transmission I was pretty certain the motor was the problem.  I needed to find out if it was broken or just in need of service.

Here is the motor with the cover removed.  As you can see, there was dirt and dried grease impacted in the worm gear and motor components.  Cleaning was definitely in order.

The slides show the sequence I used to disassemble for cleaning (click picture to advance slide):

  1. ​Remove lock ring, spacer, and off-set plate from motor front.  Pull drive shaft out through back.
  2. Remove single screw holding plug assembly in place, and place plug to the side (still connected).
  3. ​Remove worm pre-load adjuster and worm gear.
  4. ​Remove two bolts from bottom of motor housing.
  5. Unsolder wires to plug assembly and set assembly aside.
  6. ​Separate motor housing halves and set lower half to the side (worm is attached to the armature and comes out with the bottom half).

​This is about as far as you can easily go.  If I had to tear down further, I would probably just get another motor.

While everything soaked in degreaser, I cleaned the worm shaft so I could set the motor to the side.  It required degreaser, a blade, and wire brush to get the worm shaft clean. 

Next I cleaned the upper housing, using degreaser first and then walnut shell media on the light corrosion.  I finished it with three coats of Diamond Clear satin finish and a thin coat of Mobile 1 on the gear shaft bushing.

Then I used degreaser, a blade, and wire brush to remove the grime impacted in the worm gear teeth.  This is easier if the gear shaft shown in the picture is removed.  It simply pulls from the gear, but note the slots on the gear end are deeper.  If you put the shaft in wrong, the unit will not go back together.  Any shims belong between the gear and housing (I had two).  After cleaning, I lightly greased the shims and shaft and set the gear to the side.

​It was time to put the motor housing back together.  It's very straight forward, but don't forget to pull the plug assembly wires through the hole as you bring the halves together.  Tighten the screws and it's ready to receive parts.

​I reconnected the plug assembly.

I put the assembly on the alignment pin and tightened the bolt.

I applied grease to the worm shaft and did a fit check with the worm gear.

​The drive shaft was difficult to work with due to the mechanism that traces the gear track during operation.  This ingenious piece of engineering deserves a brief sidebar, as it was tricky to figure out.  Here are the mechanism's two moving pieces.  The right piece has a spindle, spring (on the tang), and guide button. The left piece has a tang, hole, and guide button.  The guide buttons follow the track cast into the worm gear, as shown in the picture above.  Put the spindle through the hole so the the buttons face the same direction and connect the tangs with the spring.

Here is the assembled mechanism ready for installation on the drive shaft.

Here is the mechanism installed on the drive shaft.

Finally, it was time to put the gear assembly back together. This was difficult because it requires holding everything in place at the same time.  Especially frustrating was the tendency for the buttons to slip out of the track.  Here are the steps I used:

  • Grease track and contact surfaces on worm gear and insert drive shaft through center hole.  The drive shaft will be inside the volume contained by the gear shaft.
  • Seat drive shaft mechanism buttons in the track so that the tang protrudes beyond the edge of the gear, and set to the side.
  • Using a small screwdriver, move the small, two-lobed tab on the switch assembly back into the switch.  This is spring-loaded and must be held in place.
  • While holding the tab, insert the worm gear / drive shaft combination into the assembly without letting the buttons slip out of the track.

This is easier seen than described.  The final result should look like the picture. 

Holding everything together, turn the assembly over and insert the hardware in the reverse order it was removed (round shaft key, spacer, and ring lock).  The gear and drive shaft should be secured and ready for the cover plate.  Now would also be a good time to put the worm pre-load bolt back in place.

The unit is now ready for the plastic cover.  The remaining modifications (wiring, switch, and modulr) will be added to this walk through when I get to the interior portion of the resto-mod.

SUMMARY:  This job was a 4 out of 10.  It was pretty straight forward from a remove, clean, inspect, and assemble perspective.  Putting things together required a little patience and dexterity.