SII Wiper Motor reassembly issues

Scoutboy74

Scoutboy74

Moderator
While I have easy access to my wiper motor, I decided to give it a good once over to make sure everything is tip top. I removed the two long case screws, the end cap and then removed the armature assembly with windings and worm gear shaft so that I could shine up the copper contact surface where the brushes sit. I then reassembled everything. It all went back together nicely, but now the external shaft that rotates and connects to the wiper arm bracketry is bound up. Before I could rotate it fairly easily by hand, but not now. I know there aren't any parts missing. I didn't overtighten the case screws. I have taken this gd thing apart and put it back together numerous times always with the same result. The only thing I can think of is the worm gear portion of the shaft isn't meshing with the plastic gear in precisely the same manner it was when removed, but there are no alignment marks on it, so how do you know when it's right? It doesn't seem like it should be that big of a deal. It's just a worm gear that meshes with teeth on a wheel. This frickin' thing has driven me to drinking hard alcohol. Before I started this I had two functioning wiper motors. Now I have none.:mad5:
if anyone has successfully overhauled their wiper motor, I'd be interested in hearing how in the hell you managed to get it back together without having things bound up. Tia
 
Buehler...buehler...hmm, nothing but the gentle, sweet singing of leaves in the wind. So nobody has ever successfully (or even unsuccessfully) r/r'd a Scout II wiper motor? C'mon now. I know this isn't rocket science. It's just an electric motor, but obviously there is some simple yet critical step that I'm missing. Maybe the case bolts need to be torqued down super tight? That doens't make sense, but I'm just about ready to try it.
 
I have never taken one apart.

I did replace one in another "old vehicle" - not IH -- many years ago. I vaguely recall that you cannot tighten the "bushings" ("copper" / "brass" metal) on the "shafts" too tight -- especially the one connecting the shaft to the rotating arm of the wiper motor.

Were the two motors "exactly the same"? You might have mixed some of the parts... Did you replace some parts / brushes?

Not that this helps much....
 
Thanks Robert for weighing in. Yes they appear to be identical. No mixing and matching as I only worked on one motor at a time. I did not replace the brushes as they have plenty of material left. All I did was dis-assemble, shine the copper contact surface and re-assemble. I've even tried loosening the case bolts to the point of them being sloppy. When I tried rotating the external linkage under this condition the worm gear shaft/armature assembly wanted to move in/out rather than rotating like it is supposed to do. Perhaps I didn't get the worm gear portion seated in far enough? You'd think if that was the case, I wouldn't have been able to get the cover piece back on as easily as I was always able to. This is a vexing problem.
 
Guess I was really bored.... I went downstairs and rummaged thru "the parts collection".

I found 3 wiper motors (GM; non IH)... Didn't remember I had that many. 2 used; 1 nos still in the delco box..

None of the shafts move freely.

Fwiw :gringrin:
 
Well, that's an interesting observation. Now I need to provide some more back story. Let's start with motor 1. This was a good-looking spare of unknown operating condition. To be honest, I don't think I actually tried to spin the outer arm before I tore into it. As a matter of fact, I didn't verify that the damn thing actually worked at all before I stripped it down. So my initial post in this thread isn't entirely accurate. After the first re-assemble, I hooked everything up and shot some juice to it to see how it worked. Low speed would work, but not high speed so much. It tried to, but just didn't have enough poop to complete even one cycle.
So then I examined motor number 2 which was very fugly on the outside, but had been functioning flawlessly in hooty. The external arm could be moved by hand with some effort. I then jumped to the conclusion (perhaps incorrectly) that the reason motor 1 seemed weak is because something was in a bind. So I played around with it a bunch more and could never get it re-assembled so that the external arm would rotate by hand. Then I got the brilliant idea to dis-assemble motor 2 to see if I could see any obvious differences between the two. While I was in there, I shined up the copper surface just as I'd done on #1. Put it all back together and then I couldn't spin it's arm by hand any more either! I never hooked that one up to test it under power as I figured I'd boogered something on it as well. Now I guess I need to hook #2 up just to see if it functions properly. If it does, then I guess I can safely assume that #1 is just a piece of shit.
 
Okay I just came back from a quick diagnostic session in the shop and I made some interesting observations. I connected motor 2 which was the fugly one that had been in service in hooty since god only knows. I clamped it to the firewall for ground supply. At first when I turned the switch "on" nothing happened...shit!
Then I loosened the case bolts slightly and tried it again. It began to show signs of life. So with it turning rather laboriously under power I began adjusting the screws much like you would adjust the idle mixture screws on a carb. There is a definite sweet spot tension-wise for these bolts to be set at. Too tight and it binds up. Too loose is just as bad. So once I got that motor in optimum tune, I decided to throw #1 up there and repeat the procedure. While I got it adjusted the best I could, it still doesn't function as well as the other one does. Clearly this motor has some additional issues that need to be addressed by someone more competent than I before it could be pressed into service. The good news is, I can go ahead and put fugly motor back into service and move onto the next project. I guess this just proves the old adage that you can't judge a book by it's cover.
I still wasn't able to move the arm by hand on either motor even with the case bolt tension set at the correct amount. Apparently the ability or inability to turn one by hand is not an accurate means of assessing the health and functionality of these motors.
 
Last edited:
Trevor: the binding could be that you got some spacer and/or thrust washers mixed up or out of order. You didn't say what kind of motor it is, American bosch or autolite. I'm assuming American bosch, I've seen more of those on other makes of rigs. The armature needs some end play, there's a set screw in the gear housing parallel with the motor. As you're torquing the thru bolts when attaching the motor, the set screw May need adjusted to keep the armature free. I don't recall the spec, but a little armature end play of .005" is enough. Rapping the housing with a hammer handle when all is torqued down will re-seat the bushings/bearings and help keep the armature free to move. After that, you put the gear end together. I use a white grease like lubriplate for the gear end.

Ihonlynorth just Happens to have a pdf of the outlay:
http://www.google.com/url?sa=u&start=9&q=http://www.forums.IHPartsAmerica.com/attachments/basic-tech-questions/2362d1220727861-location-winsheild-wiper-motor-Scout-II-wiper-pictorials.pdf&ei=426ksef-cytcnpiuinsp&usg=afqjcnfgv2va26oybhvd8w6f8o8chver1q

Don't use what could be a guud motor in drag:gringrin: situation
good luck!
 
Last edited:
Wow thanks greg! I didn't actually see a brand identifying either motor. They both had the IH logo stamped on the case with a part number. Fugly betty motor seems to be working just fine so I'm just going with that one again. I did notice the set screw on the gear end and wondered what the h e double hockey sticks it was for. I'll do some more playing around with dapper dan motor and see if I can't get it working better following your instructions. In your opinion greg, when everything is set up properly, should a fuller be able to rotate the external shaft by hand?

Edit: it looks like the autolite from the diagram. There were no removable thrust washers on either end that I could see.
 
When you resurface the commutator the turning resistance will increase untill the brushes reseat. Hand turning the driven gear gives you a low mechanical advantage. A very small increase in the armature's turning resistance will be multiplied
10-20x depending on the gear reduction ratio. You are probably seeing a normal turning force.
 
Trevor: I never tried too hard to turn the output shaft by hand. Being a right angle drive some are susceptible to turn, many are not and it is real easy to strip the plastic gear as the worm is steel. The thing I watched for is how much the motor labored and got warm after it was put together and powered up. I came across some current draw specs for the IH ones some time back. I will post them later on when I find them.
 
Thanks greg. Fugly betty is all buttoned up with proper tension and working as good as ever. When I get bored, I'll play around with dapper dan had see if I can't get him to play nice also.
 
They just spring up from deep down in my lower intestines. That would be awesome if you can make it. Hopefully the econazis continue to be stymied on their efforts to close it all down so that only "enlightened" granola munching types can enjoy it. They're persistent bastards.
 
You must log in or register to reply here.
Back
Top