[Staowners] Wiper motor repair

[David Reina]

Hi all,

The wiper motor on my new drophead was not working.  I did a repair  
the other night and after seeing the condition inside the gearcase I  
thought I'd suggest to others to check a wiper motor if it has never  
been serviced.

When I switched on the wiper the motor body got warm but it did not  
run and I thought it was going to be toast.  I removed it from the  
car on Saturday and when I opened the gearbox I could see why it was  
not functioning.  The original white oxide grease hat totally  
ossified  into a clay like substance.

When I dug  out all the old grease and bench tested the motor without  
the gear in place it ran OK.  I continued to disassemble the motor to  
check the commutator and put a drop of oil on the motor bearings.   
The factory manual says to clean out any carbon dust from the  
commutator bars which I did with a dental pick and then I gave the  
commutator  a polish  with some 1000 grit paper followed with a wipe  
down with acetone.

I also had to use the dental pick to clean all the gear teeth. The  
whole procedure was pretty easily done and by the way the motor runs  
in the same direction whichever way you hook up the wires.  I should  
also say that this wiper motor is from a 54 car and is a single speed  
without the self parking feature which would add another level of  
mechanical and electrical bits.

I then tried to hand pull the cable which is driven back and forth by  
the motor.  I found this to be moveable but pretty stiff and thought  
that can't be good for the motor.  I wasn't sure if I was going to  
make a mess of work for myself but I pulled the whole inner cable out  
of the sheath so I could lubricate it.

I squirted some oil down into the sheath and on the shafts of the  
wiper posts.  It was late at night at this point and I was too tired  
to crawl under the dash to squirt oil at the two swiveling assemblies  
but I think this would be a good idea at some point.  I then coated  
the whole cable with white lube and tried to reinsert it into the  
sheath.  I had a small moment of worry as the cable hit the first  
pivoting assembly and did not want to reengage but I found by turning  
the cable gently it would pass through the first and then to the  
second wiper position.  Now with the lubrication the cable moves back  
and forth easily and smoothly.

By the way my wipers were off the car while I was putting the cable  
back into the sheath and I think this is necessary in order for the  
cable to reenter the under dash mechanisms.

I repacked the gearbox with some white lube, although I don't think  
this is as high pressure a grease as the white oxide grease called  
for in the manual.  I didn't use some of the other grease I had  
around the shop, like wheel bearing grease because there is a bronze  
bearing in the motor assembly and some greases will attack the bronze.

I also tried unsuccessfully to repair with epoxy the rubber mounts  
for  the wiper motor.   This looked like it would work until I got to  
actually tightening the mount in place at which point the epoxy  
joints all failed.  For the moment I have the motor fastened in place  
with big cable ties and a new mount is on my "need to order" list.

If you want to do  a quick check on your cars wiper , just remove the  
three mini bolts from the flat plate on the side of the wiper motor  
unit and you can see the gear area with the grease packing.  After  
seeing this one I am going to check my other car.

Regards,
Dave Reina