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Just burnt up the wiper motor...

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T

tdskip

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I put 12v to the wiper switch to see if the switch was OK. No on/off indication so 50/50% bet which I lost - ha. The wipers immediately came on, then stalled, and when I looked up from under the dash I could see I let the smoke out. Oops.

So a couple questions if I may;

1) Was it 12v to a wiper motor that can only handle 6v that did it?

2) If I did in fact nuke the wiper motor will later wiper motors fit? That would give me a dual speed motor, yes?

Thanks guys.
 
Was the wiper motor stock? How long were they left on? Are you sure it was wired correctly? Had this motor worked before? Just a couple bits of advice other forum members gave me. Use a continuity light to check switches (with the power off of course.) Another bit of information they gave me was to put an inline fuse in between the item you are hooking up and the power into the unit (I learned that lesson the hard way.) My knowledge is limited on later Sprites, but my stock bugeye wiper motor is 12 volts. Unless you had the wiper motor wired wrong to begin with, I can't see that you did anything wrong. If you aren't sure if you burned the windings, can't you ohm them to be sure?
Kevin
 
It'll be a 12v motor for sure, but till you take it out it's hard to say if you've wrecked it. More likely had a dead short in the wiring. Wiper motor wiring isn't 100% straightforward, even for single speed wipers. Check a circuit diagram to see what you did. Usually the power for the motor is supplied directly to the motor, the power for the parking comes from the switch, which turns on the motor by providing a ground.

I can't say if a 2-speed wiper will fit or not, but If I were to bet, I'd say there's pretty certain to be one that will. Spridget owners can advise!
 
Sounds like you burned wire in the harness and not the motor itself.
 
Two speed motor will work, but has to be mounted in a different location.

Wiper motor has 3 connection, including dedicated ground. Check the wiring diagram for which terminals you used for power.
 
Early "square" motor, or the later round one?

Early square motors typically had one "hot" connection and the dash switch completed one of two (on 2 speed motors) paths to ground. What you may have done is connect 12V across a combination of wires that was never intended to have power across it (i.e. perhaps you connected the power across the two ground wire connections on the motor). The self parking feature complicates the wiring (and increases the possible errors) a bit.
 
Hi guys - thanks for the fast responses.

After I wrote this and went to go work on the horn I was kinda thinking that what I wrote didn't make any sense. Happens a lot - grin.

Some of the wiring to the [edit] wiper [end edit] is exposed at the connections and visibly thin/corroded. Does that make it likely that smoke was from the thin/corroded wires struggling to get the 12V though?

Hi Doug - I didn't change the wiring all I did was get power to the switch. It may well have been goofed up previously...
 
tdskip said:
I didn't change the wiring all I did was get power to the switch. It may well have been goofed up previously...
Click to expand...

Well, that's kind of my point. The switch on the early wipers should be a path to ground.

It seems to me that on some of my older LBCs the wiring to the wiper motor is very thin/light. If your wiring was corroded you may have had resistive heating right before the motor. Hopefully that was all that caused the smoke.
 
Ah, bad assumption on my point. Power to the wiper motor controlled by ground, got it. Now. Finally. So it is my fault.
 
After dinking with wiring and doing something I'm not 100% sure of I use a hose clamp to hook one end of a inline fuze holder to a battery post and use the bolt on the battery cable to hook up the other end. That way you have the entire system protected if there is anything wrong. Went thru a bunch of fuzes trying to find a dead short a DPO had wired into my BE.

Kurt.
 
Well it looks like I got lucky. Exactly (as usual) as Doug suggested it was the wiring and it does not appear I fried the wiper motor.

I started trouble shooting the fuel gauge and noticed that there were several power wires hung off it, so I made sure they were supposed to get power (see Doug, I am teachable - ha!) and then connected known good switched power and the fuel gauge started working. I then check and sure enough the turn signals worked and wiper motor parked. Phew....
 
Oh nice move. I love it when a plan works. lol.
 
I'd call it lucky I didn't fry anything, lesson learned. Tips and coaching here were a huge help guys, thanks.

I ran a new wire from the fused circuit to the sender and now everything works. Blinkers, wipers, fuel gauge, everything. Well everything except for the lights but that switch broke and I know how to run that. Super cool!
 
That's really good news! Wiper motors aren't cheap so I'm glad yours is still working!
 
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