Testing Jim's Wiper Motor

[Gary Lewis]

Anyone have a wiring diagram for the 1990 wiper motor?  I'd like to test it before sending it to Jim.  But I can't find a reliable diagram and I don't want to burn it up - if it is good.

[myrl883]

That motor was used through early '94. I can only print and scan wiring diagrams for '92 and newer, but the controls were different. I tried... If the newer wiring diagrams will help, let me know.

[Gary Lewis]

If the connections are the same then maybe you could just list the wire colors and what they do - if that is easier than scanning.  I have the original wiring so can determine which goes where.  But, if it covers the motor it would be a big help.  TIA.

[85lebaront2]

Won't post, check your email.

[Gary Lewis]

Ok, Bill wins the prize.  Thanks!

[85lebaront2]

That should be valid from 1987-93 or so when the motor changed. At that point it became a single plug. Service and rebuilt are the late style with a pigtail for the earlier harness.

[Gary Lewis]

Houston, we have a problem.  When I put battery voltage to either the green-circled connector or the orange-circled connector, with ground on the red-circled connector I get nothing but a spark.  Am I doing it correctly?

I'm guessing the motor is good from the fact that it pulls current, but the bushing/bearing is seized.  Suggestions?

[85lebaront2]

Motor is a permanent magnet unit with the brushes in the gearbox end, open the gearbox by unclipping the switch cover and lifting it off. With it off, see if the inside looks corroded, if not, try gripping the motor shaft and see if it will turn, if you can turn it, try powering it again.

If you need to pull the magnet portion off, keep the motor shaft in place so the brushes don't come out. Armature may be rusty and binding on the field magnet.

[Gary Lewis]

I have the snap-on cover off, but that just gets access to the output shaft of the motor with its worm gear, the big worm gear, and the park brushes. Getting on the output shaft with pliers isn’t easy as there’s just not much room, but I can rock the shaft back and forth slightly and then it stops. I’ll lube the bushing, rock it some more, and then hit it with 12v again.

But you don’t see any problem with my wiring?  (I can’t imagine that I’m wrong on something so simple, but.....)

[ArdWrknTrk]

Man, you should have seen the crap that came out of the race outboard's starter the other day.

Chunks. And the brushes in the bottom were nubs on springs.

Thanks for your efforts.
My wipers are dead again today.
There is no fuse labeled for them and my evtm is home.

[85lebaront2]

Jim. it looks like the circuit breaker is part of the switch from the diagram I have. I have the 1990 owner's manual I can go look at if that will help.

[85lebaront2]

Wiring looks good, you have a low speed feed and a high speed feed and ground.

[Gary Lewis]

I think that there might be similar "stuff" in this wiper motor.  I can turn the armature a degree or two, but there are ugly noises coming from inside the motor when that happens, like the armature is against field.  Or, if it is rust like Bill said, there's a LOT of rust in there.

So, I decided I'd pull the motor off the gearbox.  And the heads snapped off of both of the Torx screws that hold it on.  They have decided to take up permanent residency in the alloy gearbox.

Then I thought I'd just use a soft hammer to take the motor off the gearbox.  Looks like I can do that, but the shaft isn't following and I know those brushes are going to pop off the commutator.  Should I continue?  Or, is it time to say this one is toast?  

[85lebaront2]

If the shaft is staying in the gearbox, then the brushes should stay in place. Unfortunately, it may be toast though.

[ArdWrknTrk]

So I should be looking for a wiper motor?

Bill, any chance you have a p/n for that adapter harness?

I got the new bendix gear for the 9 tooth Mercury starter that fits the aluminum flywheel today.
Maybe now we can listen to this ported  six cylinder beast rip.
The smell of 2-stroke at 32:1 mixed with 101 blue is going to take me WAY back!

[85lebaront2]

Jim, no I do not, I discovered it while looking at them on-line. Motorcraft shows it coming with the motor. The wiper harness (unfortunately already on it's way to Podunk) from the F450 could be used on yours to convert to the later motor. I can send Gary the pdf so he can convert and post it for you. I would do a quick voltage check at the motor plug and make sure you are getting power under load (wipers on). If not, then depending on what your truck has, it could be a switch or delay module problem.

[ArdWrknTrk]

Yeah I have my 1987 evtm now

[Gary Lewis]

I’m almost down, or in, to the delay module - assuming that’s what it is. Got the switch out but getting to the module isn’t easy - especially when the ants are attacking. Yep, found a colony of ants. And a snake skin. So I’m looking before I reach.

[Gary Lewis]

Here are the diagrams Bill sent.  First is the 1993 interval wiper:




Then the 1996 interval wiper:

[85lebaront2]

The reason for sending these is twofold, first to show where Ford played musical locations with the ciecuit protection on the 1987 up wiper motor and second to show how a single plug motor can be used to replace a dual plug one. The circuits are the same, Ford just combined the 2 three pin plugs, one for the motor and one for the park into a single six pin plug that sits on the gearbox portion of the motor.