Wiper motor overheating?

[RickTheEngineer]

Hey everyone, I have a question that's been on my mind for quite some time. On my CUCV my wiper motor's fluid pump broke so I replaced it with a cheapo one from AutoZone. I noticed that the motors we almost too weak to move the wipers, so I tried swapping them... 4 more times with the same results. I finally decided to get an ACDelco rebuilt one and man it works great. However, out got really slow sometimes, and today actually BARELY moved and it stopped working. I can't to realize the wiper motor was burning hot, which made me think it overheated. After leaving it alone for 20 min, it cooled off, and worked well but still a little slow. I removed the capacitors and still the same result. Maybe there's too much resistance in the wiper linkage? I was thinking about removing the cowel and just lubricating everything. Any other thoughts?

 

[Hendersonr]

Trace the wiring from the wiper motor and look for bad connections. Also, check to make sure the windshield wipers aren't pressed against the window. And yes, lubricating everything would be a good idea.

 

[Barrman]

Check all that is listed above. But another good idea is to run a ground wire from one of the holes on the wiper body to the fender or any place you want on the truck body. The wiper ground strap design is pretty cheap.

 

[RickTheEngineer]

I like the idea of running my own ground. I would have wondered if the motor was getting a good ground. (Maybe it's not getting enough current, causing it to stall and cook the internals?). Also, Hendersonr, when you say if the wipers are pressed against the window, do you mean if the wipers are creating too much friction? The wiper motor works pretty well when it actually rains, but it's slow as heck when it's dry and you want to use the washer pump, and sometimes overheats and stalls

 

[dependable]

Wiper motor is on same circuit as fuel heater in stock Stanodyne fuel filter base. May not be the problem, but something to check (amps draw on fuel heater circuit) this did cause a problem on one of my 1008s. Also look for melted the wiper wires in harness, near the fire wall, a shorted wiper motor can cause wire insulation to melt, and you might get an intermittent short.

Another thing to check is for physical obstructions to wiper linkage. Sometimes debris builds up, often with the help of rodents. Not a bad idea to spray some lube on the linkage while you are in there.

Edit: In response to the newest post, the mechanism for the washer pump can jam and over load the wiper motor. This can usually be fixed if you have time for "micro mechanics" and have a parts motor. Most would try yet another wiper motor.

While I seldom bother to do so, going to the electric washer pump chevy switched to in the late 80's is not a bad idea.

 

[ssdvc]

"Another thing to check is for physical obstructions to wiper linkage. Sometimes debris builds up, often with the help of rodents. Not a bad idea to spray some lube on the linkage while you are in there."

This has happened to me. Wipers slowed to next to nothing in one of my 1009's and when I took a look under the hood and into the cowl space, I had a HUGE mouse nest right around the wiper connector arm. Removed the nest, wiper worked great.

 

[patracy]

Does your truck have the filter capacitors in line with the wiper motor as well? I removed mine from the circuit.

 

[antennaclimber]

I agree with checking the linkage to ensure that it moves freely. I had the same issue on one of my trucks. Some lube on all of the connecting components helped substantially and kept the motor from overheating.

The wiper motor has +12 volts to it from the fuse box. It gets a ground command from the wiper control switch for Hi and Low speed on wire PPL-92 and GRA-91A.

On the wiper motor I purchased from Auto Zone, the case of the wiper motor does not need to be grounded for it to work. The case is isolated and adding a ground to it did nothing. I believe that the GM ground for the motor case was for electrical noise suppression emanating from the internal components.

 

[RickTheEngineer]

As mentioned in the original post, the capacitors were removed, no change in result. As for the grounding thing, I too noticed the ones from AutoZone are not grounded the same way, although I do have an ACDelco one and it does have the strap. I'll add the ground just in case. I inspected ALL wires around the fuse box and it looks awesome. The fuses are all in great shape, and all the wires by the fire wall are in great shape. No corrosion on any of the connectors. When I am able to take the cowel off, and clean the inside I'll report on the findings. I'll grease up the linkage as best I can. Also, I am not sure if my wiper arms are OEM or not so I'm gonna ask you this... Do your wiper pop up?? Mine dont. It also has a pin drive for the wipers. Thanks!

 

[dependable]

See if they work with soapy water on the windshield as lubricant. If they do, the wiper blades might be part of the problem. I had a set of new blades that made too much drag recently. I put some electrician's pull tape lube on windshield and that helped break them in.

 

[rchalmers3]

The last time I had that problem, I found the wiper arm shafts were tight in their housings. It was so bad, I almost couldn't get one them apart to be cleaned and lubricated, but afterwards both the old motor and the new replacement motors operated the wipers at good speed.

Rick

 

[cucvrus]

Yes it is worth the effort to remove the entire wiper transmission from the cowl. It is also worth the time to press grease and motor oil into all the moving parts of that wiper transmission. If you spray WD40 or any other aerosol lube. You are wasting time and only doing a temporary fix. if you take the time and do it right you can expect years of squeak free service. That wiper transmission should be as smooth as a wind vane when you are done cleaning and lubing it. Nothing more irritating then a squeaky wiper transmission. And I buy all my wiper motors at Autozone. No issues yet with them that I do NOT encounter with stock parts. Keep it simple, take care, and maintain what you have. It will last for years. A C Delco are made in Mexico at the same plant.

 

[Tinstar]

Agree
Take the time and grease everything.
It will take more time initially, but will give you years of smooth operation.

Mine were all extremely dry on initial inspection.
Some grease applied and no issues since.
I run a ACDelco unit and it also has been trouble free.

 

[RickTheEngineer]

I am going to resurrect this old thread and talk about what has been happening. My wiper motor still does this, and I've replaced it with an ACDelco one. The wiper linkages were all greased with lithium, and I did remove and cowl and it was all clean under there. Wiper linkages shows little to no rust or corrosion. I replaced the wiper switch in the column as well for a new one (did help speed it up, but still overheats and stops). All connections are clean/perfect, dialectic grease and all. Cleaned grounds from wiper to firewall and that's all good. I even replaced the springs on the wiper arm for ones that apply less force. What am I missing??

 

[firefox]

Just an idea. Remove the wiper blades and run it for a long time jut to see if it over heats.
Who knows, you might have gotten a bad motor. At least this will isolate the problem a bit more.
Good luck

 

[RickTheEngineer]

I'll give it a go in the morning, although if it doesn't, it's going to definitely become harder to solve... I saw on the civvy version, some had actual circuit breakers. The CUCV doesn't have any do they? I ask because the wiper motor will indeed start working again after it cools/un stalls. I will try moving the wiper linkages by hand to see just how bad the resistance is, but u just greased it all. The mind boggles. Any other advice? Are there any other grounds I'm missing?

 

[firefox]

One other idea I had was wire it up to the battery directly, measure voltages to check. and
see what happens. I am guessing here.
Good luck

 

[RickTheEngineer]

I can give that a try, but that of course means the wipers will not turn off. But I suppose it would be a good chance to see if it stops working. I just wonder why it stops but then actually starts again. Considering that there are no circuit breakers that is

 

[german m1008]

.......You also changed the wipermotor seal to the firewall?
When the seal is broken or something else and the wipermotor is too tight, the wipermotor linkage can't move freely......And then it gets hot and burns

 

[GREENMV]

I had the same slow wiper problem with mine a couple years ago. The fuse in the fuse block was actually lose in the female connection side of the fuse block. It had overheating / melted a little and was not seating tightly and making a poor connection. it had the right size fuse so this must have happened before I got the truck. I pulled the fuse and cut some thin copper shim material I had and put it on each blade of the fuse to make the thickness a little larger and stuck it back in the fuse block to make the connection tighter. The wipers had more oomph and have been working good ever since. This fix saved me from pulling and rewiring the fuse block or running power to the wipers another way. I assume the loose fuse was screwing with the amp draw when the wipers were on?