Dibbons

Purchased over ten years ago and rear wiper never worked. For one thing, found out this week the 20 amp fuse in the passenger side kick panel was missing. So I removed the rear hatch panel and began to snoop around. Of course, I found electrical tape around the left wiring harness that passes from the body into the hatch. The right harness is still passing inside her rubber booty. Removed the wiper arm and wiper motor.

Put 12 volts directly on the two tiny wire connections on the motor and it would not spin/move/rotate--nothing. I did feel/hear a very faint click. Then it hit me, the shaft on the motor might just be rusted so bad it is more or less frozen. With pliers I tried to move the shaft and it would not budge except for a tiny little bit. I tried the motor again, and if it's not my imagination, the motor moved the shaft a tiny, tiny bit. So my theory/diagnosis may very well be correct (and would explain a lot of the other Cherokee rear wiper motor "failures). So I intend on bathing the shaft in penetrating oil over the next couple of days to find if I can free up the shaft enough to put it back in service.

In the meantime, I worked on the broken tube that supplies the rear window washer. I decided to use a fairly stout clear plastic tube left over from a can of Eastman inner frame anti-rust coating. The tube outside diameter measured exactly 5mm so I first drilled a 4mm hole and then a 5mm hole. The tube fits satisfactorily snug that I don't even see any reason to glue it in place. Just need to cut it to size during final reassembly. I will have to use the stub of the leftover broken plastic tube so I can make it work with the smaller black rubber tube attached to the wiper arm itself, kind of a male/male adaptor if you know what I mean.

Now I need to find a 13" wiper arm replacement refill (don't want to spend for an entire new arm). I don't remember seeing just the refills in AutoZone the last time I shopped. Might have to special order it or find a refill online. I sprayed some penetrating oil over the spring and hinge of the old wiper arm and it seems to be free enough to put back on as is (might repaint it first).

I noticed the washer tube has a one-way check valve inside the blue plastic adaptor. Appears to be a tiny shiny metal ball with a weak spring that is overcame by the water pressure when the washer pump turns on. Interesting.

Dibbons

Update: Today at noon I was able to use a center punch and claw hammer to drop the main shaft from the body. This was after I had drilled off the four rivet heads that holds the cover plate on the mani body. What I found was the shaft measures 10mm, my finger pointing in the photo shows the lower bushing measures 13mm (outside diameter), and the upper bushing measures 12mm (outside diameter) in the photo which has the yellow pen tube pointing it out.

The lower bushing slides freely up and down the shaft without a problem and it also spins freely on the shaft no matter where on the shaft I slide it. The upper bearing/sleeve does not spin nor can I slide it up or down, it's solidly in place at the moment. Now the problem for now is the fact that I am not sure how those two bearing/spacers are supposed to be working when the wiper functions as it should: Might both be fixed? Should both be free/movable? Should one be free and the other one fixed? Any forum members have a clue? To be continued ...

Dibbons

Update: i ran jumper wires to the motor with the shaft removed and it spun. Not real fast and sounded kind of weak, but maybe that's all the motor can put out even when new. I am now soaking the shaft with the immovable upper bushing in Evaporust. I put the jar with the Evaporust in the refrigerator so it would not evaporate so fast (running in the 90's around here this week). I also tried to sand/brush the inside of the main body tube in the area of the immovable bushing with a Dremel tool. Did not make much, if any, progress of encouraging the shaft to spin more freely.

Dibbons

Update: After various sessions with penetrating oil, brake cleaner, mini-brush on Dremel tool, Evaporust, I tapped on the upper stuck bushing this AM and it slid free from the shaft. Now I am almost 100% certain that both upper and lower bushings should allow the shaft to spin freely when put back together. Definitely still going to be a sore spot (achilles heel) when a drop or two of water finds its way down the shaft to the bushing.

Now when I spin the upper bushing in the location that I found it stuck on the shaft, I feel a slight roughness, but I don't see much of any buildup on the shaft. Maybe what was there initially dissolved during the soak in Evaporust in the refrigerator the last couple of days. I'm going to soak the loose bushing and the shaft (now free of the bushing) in Evaporust for another 24 hours or so and then take if from there.

I tried to punch out what remains of the four rivets that held the bottom plate on but nothing doing. Now it looks like those were not really rivets. Can't tell if the are just pins pressed in from one side or if they may even have threads. I could leave the stubs of these rivets (or whatever they are) in place and use them as "locating dowels" upon reassembly where I could use something like epoxy over the top of them to secure the plate. On the other hand, I could try to drill them out some in order to accommodate four small screws (which would be kind of a pain in the butt). I'll have to think about it.

Kap

This is great info with guidance. Mine stopped working after the vehice s at outside and unused in winter for more than six months while away. Worked fine until then. Always figured it was frozen due to rust or a wiring problem after bitter cold, plenty of temp changes, lots of moisture, etc.

Dibbons

I drilled out the "rivets" or whatever they were and am looking for some small screws (have some 3mm screws on order). In the meantime, with everything greased and put back together and after applying 12 volts to the motor terminals the shaft finally began to rotate back and forth about 90 degrees.