Help troubleshooting wiper motor

[BrandonBJ8]

Getting my wipers working is the last thing I need to do for my car to pass the safety inspection so I can register the car. I've checked the switch and it appears to be working as the multimeter moves when I turn it on and off. Same with the wires at the end of the wiper motor so I think it is the motor.

I've removed the motor from the car. Attached are a few pictures of the inside of it. Any ideas? Is there a way to clean it out or what else should I test?

Thanks!

 

[Bob_Spidell]

Have you put 12V power to the motor? If so, does it turn? Last photo shows what appears to be a corroded/cold solder--could be some of the problem.

 

[BrandonBJ8]

Have you put 12V power to the motor? If so, does it turn? Last photo shows what appears to be a corroded/cold solder--could be some of the problem.

Bob - What's the easiest way to do this? Where do I connect the wires to? (Can I do it from a regular 12v battery?) Sorry for the basic questions, want to make sure I test everything properly. Thanks!

 

[John Turney]

Bob - What's the easiest way to do this? Where do I connect the wires to? (Can I do it from a regular 12v battery?) Sorry for the basic questions, want to make sure I test everything properly. Thanks!

1. Put it back together.
2. There are three wire connection points on the end of the motor furthest from the gearbox (what you have open in your photos).
3. Connect battery + to connections "1" & "2".
4. Connect battery - to connection "E".
5. If it runs, disconnect the + lead from connection "1". It should run a little more and stop at the parked position.

 

[Bob_Spidell]

I don't have a schematic in front of me, but 'E' usually means 'earth' (or 'ground'/common) and should probably be connected to battery positive. I suspect it won't matter, except the motor may run in reverse direction.

 

[TR3driver]

I don't know much about Healeys, but those photos sure look similar to the DR2 motor used on later TR3/A. If so, you want to apply power between terminals 1 and 2, not to both of them at the same time. The switch should ground terminal 1 to make the motor run continuously, then the park switch (that round cover with the red wire) will also ground terminal 1 while the motor is away from the park position.

Polarity actually doesn't matter. The motor will run the same direction for either polarity, because of the wound field coils. If you swap the polarity, both the field and armature develop opposite polarity magnetic fields, so the motor still turns the same way.

What you've got open there is the gear housing, not the motor itself. Looks OK to me, tho obviously it could use cleaning and re-greasing. Any quality lithium grease will do. I would want to also remove the end plate from the motor, to inspect the brushes & commutator, plus maybe just a drop or two of oil on the end bushing.

 

[BrandonBJ8]

So I put power to the motor and nothing happened. How should I go about troubleshooting the motor to see what the problem is? Thanks!

 

[BrandonBJ8]

Here's a picture of the wiper motor opened. Any thoughts?

 

[healeyblue]

Another problem that will prevent it turning is if the drive cable or gear boxes are packed with dried grease, it can prevent them from turning. When I restored my motor I disassemled all gear boxes and the cable assembly and cleaned it all up and re-greased before putting it back together. Now with it on the car they work smoothly and quietly. Prior to dis-assembly I could not turn the cable or gear-boxes and I doubt the motor could have either.
JIM

 

[BrandonBJ8]

Another problem that will prevent it turning is if the drive cable or gear boxes are packed with dried grease, it can prevent them from turning. When I restored my motor I disassemled all gear boxes and the cable assembly and cleaned it all up and re-greased before putting it back together. Now with it on the car they work smoothly and quietly. Prior to dis-assembly I could not turn the cable or gear-boxes and I doubt the motor could have either.
JIM

Even if this is the case, would I still hear or notice the motor trying to move when I put power to it? When I connected power to it from the battery, I got a little spark but that's about it.

 

[TR3driver]

The wiper motor is not particularly strong, so you might well not notice anything beyond the spark. From what I can see of your photo, the motor looks OK; and the spark shows that it is drawing at least some current (meaning it isn't a simple open circuit). So I will agree with Jim, pull the gears out and make sure the armature (motor shaft) can turn freely, then try again. Note that you will have to reinstall the end plate; the armature won't turn freely without the bearing to support it.

In your first photo, there is an E-clip under the grease, that holds the brass finger and connecting rod in place. Clean the grease away and take another photo, then remove the clip, finger, any washers (don't recall offhand) and the connecting rod. If you want, you can retry the motor at that point; but it is probably best to go ahead and pry off the clip on the bottom of the unit so you can remove the big gear along with it's shaft first. There may be a thin washer between the bottom of the gear and the housing (again I don't recall offhand), if so don't lose it.

 

[TimK]

My solution to the same problem you have was to buy a replacement used motor. I found one on-line. The shipping from England was more than the cost of the motor (about $60 in total), but well worth avoiding the hastle of finding someone to rebuild mine. You could try, however, to find an old-time motor repair shop to at least diagnose the problem.

 

[GregW]

3. Connect battery + to connections "1" & "2".
4. Connect battery - to connection "E".

I don't think that is correct. E and 1 are both grounds. 2 Is the hot lead. Try wiring it up that way. Though the spark you saw may have been the motor saying goodbye.

 

[healeyblue]

Even if this is the case, would I still hear or notice the motor trying to move when I put power to it? When I connected power to it from the battery, I got a little spark but that's about it.

Not necessarily. The fact that you are getting the little spark says you are making some kind of circuit, the motor could be locked up enough to not be able to turn. Unbolt the gear boxes from the cable sheath and see if that helps. Take good pictures of how it is assembled and the orintation of the boxes on the sheath so it goes back together correctly. With the gear boxes off you can then also withdraw the sheath off the cable and properly clean it up as well. There should be no resistance for the motor then.
JIM

 

[steveg]

I would send it to Star Auto Electric for an overhaul. They can probably quote you on the phone. A friend recently had his done there and was happy with the service, cost & turnaround. Our local SOCal Austin Healey Association had a field trip there and we were all impressed by their dedication to British auto electrics:
https://www.starautoelectric.com/page1.php

 

[John Turney]

I don't think that is correct. E and 1 are both grounds. 2 Is the hot lead. Try wiring it up that way. Though the spark you saw may have been the motor saying goodbye.

After looking at the wiring diagram again, you are correct.

 

[BrandonBJ8]

So I've got it all taken apart. The shaft was not turning well and it took quite a bit of force to turn it manually. Now that I've got it all cleaned out, how do I get it back in? There is this metal guard that seems to not allow it to go in. I'm worried about forcing it. See attached picture for reference. Thanks!

 

[TR3driver]

That is supposed to be the bearing retainer (and the bearing is that oval thing visible next to the windings). From that polished ring, I'd guess the bearing was seized and turning in the housing instead of the shaft turning in the bearing.

You'll have to pull the bearing off the shaft and get it to turn freely again (likely the shaft will need polishing). I'd also let the bearing soak overnight in some motor oil (it's porous bronze aka Oilite and the oil soaks into the pores of the metal to provide lubrication over time).

Then you'll need to carefully pry out the bearing retainer from the housing. Put the bearing in the housing, tap the retainer down on top of it and then insert the armature shaft again.

 

[BrandonBJ8]

Thanks, Randall! This was my issue and now the motor is working perfectly!

So I've got it all put back together and am having two movement issues with the wipers.

1. They only move about 30 degrees back and forth. I'm not sure what's the best way to correct this.

2. They're not parking correctly. I think I need to fix issue 1 first and then address the parking issue.

Thanks!

 

[Keith_M]

The rotational position of the round dome on top controls the parking point and will probably also correct the '30 degrees back and forth' problem. Just loosen the top plate screws and turn the dome until the motor does what you want it to do.