24volt/12volt wiper motor help (1 Viewer)

[sandec]

So I got a fire sale deal on a windshield frame from an fj40 in perfect shape with the wiper motor and the arms. It's out of an older fj40. Problem is I have the motor but it's 12 volt. I also have the old 24 volt motor but they aren't interchangeable. Worse yet I don't think I can find a 24 volt motor for that style and even if I could it would probably be very expensive. I have them apart and the armatures look exactly the same except the 12 volt having more windings and the shaft on the 24 volt is longer. So how can I make this thing work? My options so far are:

1) run the 12 volt motor on 24 volts and see what happens
2) Cut the shaft on the 24 volt motor, jimmy rig it and make it work. I could probably do this but wouldn't win any car shows.
3) Converter. I don't really want to buy one just to run my wipers
4) Rain-X......I want to avoid this one. Even though it's been instilled into my head I need to hate mud, I still expect to see a lot flung on my windshield when I'm duck hunting.

Maybe I should start crawling before I walk here. What makes the difference in a 24 volt motor and 12 volt motor? So far the only difference I really see is the 12 volt motor has more windings. I would suspect since a 24 volt runs with less amps, running 12 volts through a 24 volt motor is a bad idea. But running 24 volts through a 12 volt motor might be ok. I'm at least 8% sure on that conclusion I drew.

 

[veggieguy]

Put 24V through a 12V wiper motor and watch the wipers go twice as fast, and you will eventually burn it out for sure. Maybe there's a way to change the motor to 12V, but I doubt it's as easy as cutting off the shaft! MAybe an automotive electrical rebuilder could help you?

 

[sandec]

I should clear that up. It's my understanding the wire wraps on the armature is what makes it 24 or 12 volt. I would use the whole armature of the 24 volt and use it inside the gears of the 12 volt wiper housing, if I cut the shaft down it would fit inside.......Not pretty but it would fit and work fine. It would have the 12 volt brushes but I don't see how those can be different.

 

[seapotato]

I did the same thing many years ago, when the gear portion of my wiper motor crapped the bed.

I didn't have to shorten the shafts, the 24v armature fit right into a 12v housing, and worked fine for many years afterwards, and probably still is working.

Maybe the 12v motor I used was from a similar year, and that's why everything fit?

but you're right, everything but the armature is identical 12 or 24 v.

At any rate, worked for me..

cheers,
r

 

[sandec]

Thanks for the help. I did a jimmy rig job today that jerry would be afraid of slandering his good name. I ended up cutting the shaft short, drilling a hold for the bearing in the top, then drilling holes from the top of the case. The diameter was a little to small for the case to fit so I bolted in on there and put silicon all around it.........Not the pretties thing. I was quoted $400 for having the 12 volt converted to 24 volt, so I figured I'd try what I did first. I should work but if it doesn't I'll try something else from there.