Wiper Trouble

[Safetypup]

I cleaned up my old wiper gearboxes and installed them with fresh top and bottom grommets through the body. I got all excited to see some wiping... but they did not work. No movement.

I checked the 356B wiring diagram and looked at fuse position #4, and it was empty on my car.

Got a new 8a (white) fuse and when I went to install it, there was a slight buzz/hum like electricity. Hmm that is probably not right... so I removed it. I put a volt meter across the fuse #4 terminals and measured a bit over 6V.

I unplugged all the wires off the dash switch, but I still see 6V across the fuse terminals. One of the wires on the back of the wiper switch (unplugged still) is a double wire in one connector. Both wires are black with a purple stripe.

What I think is the issue is that there is a short or some other problem inside the motor unit. The electricity is going to the switch on that black/purple wire, hitting the bullet splice connector thing and going to the motor unit where a short somewhere is leaking to ground.

Does that sound reasonable? Is it easy to repair the motors or should I just pay someone to do it? Can you remove the motor without removing the boomerangs shaped piece?

Car is 1961 Roadster. Even though the car would never see rain, it just annoys me that the motor doesn't work :/

Thanks in advance.

Brian

[Safetypup]

Just realized I posted in the welcome forum. Could a mod please move somewhere better?

[Jbrooks]

Check the fuse first, then the wiring as above. And the motor will go over center in park and keep on running with out some mechanical load.

wipers are pretty easy electricaly.
The black and purple does not get voltage until you pull the switch. Then the motor runs using the black for one way, purple for reverse, push the switch in it provides the ground for park position.

[bbspdstr]

This topic is still here, so I'll take the liberty to add more info via scans of other wiring diagrams to what Brooksie provided. He is likely correct in that less drag on the rotating wiper motor will either NOT allow it to "park" at a certain portion of the contact where it should (regardless of when the switch is turned "off,") OR it's a stuck part of the winding TRYING to find a better ground.

The "boomerang" must come out (easier with the earlier than the later and easiest with a Roadster) to take the motor off the frame, BUT the cover of the motor may be removed easily to see what can be seen, tested, lubed, sprayed with contact cleaner, etc.

Just check the wiring going in to switch and motor.

(Here is where we need to hear from Jack for even more insight, huh?)

[Safetypup]

Thanks you for the diagrams!

I went to the car this morning and I did another few small tests:

- All tests done with all four wires on the wiper switch unplugged and no fuse installed in position 4

1) from fuse 4 hot side to other side of fuse = 6.25V

2) disconnecting the black/purple from the wiper motor eliminated the voltage across the fuse to 0 / no circuit path

3) opened the motor cover and it looks clean inside. Both of the little brushes on the motor are making contact and move freely. The motor spins freely by hand and the mechanism moves smoothly (there are no wiper arms installed)


I need to test again with black/purple connected again but it got me thinking - what is the correct way to connect them? I don't see terminal numbers on the motor, but maybe that's because it is still installed.

Starting from the front side of the motor as installed in the car (or you might call this the bottom wire if you imagine the motor sitting installed on the boomerang), my motor has

a brown ground wire going to a ground loop on the boomerang mount bolt

Next, a black with purple stripe wire next

Then what looks like an all black wire

Then finally at the top (or most-rearward) terminal, a black/white stripe wire.

It's a bit hard to tell since the car has been repainted a few times heheh

If any of that sounds wrong, let me know. Or maybe someone has a picture of an SWF wiper motor where the terminal markings can be seen

Thanks so much!

[Safetypup]

Just realized one of the images in the thread here has a diagram for how to hook up the wires on the motor and mine seem correct.

I guess I should poke around the motor and see what the issue could be.

[Jbrooks]

Remove the fuse, Meter the back of the switch. "Pushed in" you could read continuity on the park ground brown wire 31b from the motor through the switch to ground via 54d. So take a meter and see which two contacts read continuity switch in. Once you have these two ID'ed. "Switch in" reads ground or zero ohms, "pull out" its open to ground. Brown wires on these pins. Reading from the wire side, one wire will read ground the other open.

Then "push in" one of the un used plugs on the switch will read continuity back to the ground ( you are reading from the switch through the motor back to the switch pins 54d -31b is easy. This used black purple. The only pin left is the black wire 54 with power to the switch and motor, probably the pin with two wires in the back.

Fold the wiper arms out so you don't scratch the windshield.

Push switch in, install the fuse. Motor may bump then stop. Switch out wipers should work, push in they park.

[Jack Staggs]

Thanks for the referral, Bruce. Much appreciated.
To All: Every time any of us as professionals/experts in this field give advice, it is right up front for all the world to see. I think people are attracted to forums having long term recognizable experts.
Our names are permanently attached to it in to perpetuity, so we need to get it right. If not, we may appear to not know what we are doing. That can effect our business, as it perhaps should. Those that willingly risk their reputation for FREE over and over on forums like this do so because of passion for the work, not money! The very least that a poster can do is attach a genuine full name, first and last. After all, you are trying to SAVE money, right?
If anyone feels that this is a bit over the top, I would ask any of you that belong to forums dealing with your field of expertise (likely 100% of you) would risk your reputation on an unidentifiable moniker with an unknown agenda?
I see problems and solutions here.
If SafetypupBrain or Jbrooks, etc. hiders..?walked in my shop, I would have no idea who they could be. Sad.

[Jbrooks]

Jack

I am John Brooks my Cell 360 941 2358. I am just an old 356 guy trying to keep them on the road. No agenda, but 50 years of owning and fixing tubs. I have the publications, P tools, and spares. The younger or new guys need to learn how to fix their cars. You and I will not be around forever to do it for them. When I was in the PCA in the 60's it was a fix your car club, not the whine and cheeze crowd today. Similar with the R group now. More worried about the date stamp or decal on a screw driver than a correctly tuned idle jets.

I am willing to help if I can. I don't do this for money, just to keep them around. I still have the 356 I drove in high school.

[Jack Staggs]

OK, back to regular scheduling.
Wipers 101
. I would guess there are at least 9 different systems for 356 (Gmund excluded). This includes wipers arms that sweep in opposition to one another, arms that are synchronized (moving left to right in unison), motors that are linked to the switch by Bowden tubes, motors that have no auto stop, motors that HAVE auto stop (of various types), SWF motors of different types, Bosch motors of different types ,factory 6V and 12V motors, direct drive arm shafts, gearbox arm shafts, single speed switches, variable speed switches in 6V and 12V (this type available with options for electric washer systems), left and right hand canceling as well. I may have forgotten something, but I have never seen a two speed wiper system factory fitted to 356, as shown in a diagram in a previous post. VW, yeah.
It is possible that non compatible parts have been cobbled together over the last 67 years? No way, Ya think??? Last oddball one though our shop was a T6 with a single speed T5 or T2 gearbox wiper assy, connected to a variable speed T6 switch. They are all Porsche parts, right? Why don't they work? "When I turn them on, they never stop!"
Wipers are simple.
1 hour of thinking and typing.
By edit: I forgot to mention that wiring looms can be very specific to wiper systems. Recently I was called upon to install a loom on a T2 coupe. The customer supplied me with a loom with no markings. After the loom was 90% installed, I realized that the loom was for a T1 Speedster, and the differences became apparent. (Bring your own bacon to breakfast, don 't be surprised what you get). The wiper system was one of the problem areas. I created a supplemental loom to make the corrections, that looked factory. The owner saved a negative $800.
Did I mention that wipers are simple?

[bbspdstr]

"Did I mention that wipers are simple? "

This takes me back to the early days of a 356 "12 volt conversion."

911 or 912 motors WILL fit into a T-6 356 (even an A Coupe with some 'creativity') but the rheostat (or one-stage, off-on) switch isn't going to work...but a VW 3-stage switch will. But it looks different.

You can re-wind a T-6 6v wiper motor to be 12 volt, but that 6v switch is still the odd part out.

We learn. Now, unless a RARE collection of original 12v system parts, the entire wiper system stays 6v, fed from the 12v system via a nice Ron Francis 25 amp step-down that is discreetly mounted and wired to look "original" in and through the wiper harness. Cheaper/better. Can be used in any model wiper situation, jus' sayin.'

And this:

"I am willing to help if I can. I don't do this for money, just to keep them around."

Good platform. "We" need more here like Brooksy. Jack and I feel the same but still have businesses that can keep us from doing what we LIKE to do, like right here, like John, like all the participants here. Good or bad, a little or barely satisfactory, Jack and I still need to make some money. That's the end result of never having a "real job" with pensions or other retirement security. It's what we get for putting the cars first for almost 50 years......

Bruce

[Jack Staggs]

This works well on 12V for some applications for $40 ($58 @ Stoddard ) :
http://www.wolfsburgwest.com/cart/DetailsList.cfm?ID=113955811B
Can be done quickly in situ.
I've never been a fan of the 911 conversion. Tell me more about the 25A Francis device. I don't know about that.
Still learning about 356 after 50 years in the trenches...

[bbspdstr]

Thanks, Jack. I have a couple of those "on the shelf" but for years now, my go-to solution is:

http://www.ronfrancis.com/prodinfo.asp?number=VR-4

I use this most often. No matter how well the 6v switches and relays and all else can be with less amps and more volts, even the different wiper motor main part in 12v for the early stuff isn't all that needs to be thought about.

It helps that Ron is fairly local to me, too. Good vendor.

Why change to 12 volt? Better availability for bulbs and accessories and/or pushing electrons through a funky old harness of corrosion, faster starting? Why not change the wiper electrics to 12 v? I rarely hear that the wipers are of a concern as they are hardly used anymore. Rain-X has superseded wipers on most 356s.

[Don C]

Bruce,
You going to the "Deutsche Classic" in Oley, Pa tomorrow?
My wife and I are going, hope to meet you sometime!
Regards,
Don
White '65 356C
NJ plates

[Safetypup]

Fixed it. (And I feel kinda silly now, but I am posting to help future people that stumble here)

Opened the wiper motor cover, cleaned off the commutator, worked the mechanism back and forth by hand a bit (no wipers are installed so it moves fairly easily)

Put it back together and decided to study the wiring diagram and description of operation posted in the thread here. I remember reading on a web page for electrical engineering or something that people spend too much time measuring and testing and ripping things apart without stopping and thinking about how it is actually supposed to work.

In my initial test, circuit 4 (wipers) was drawing power as soon as a fuse was installed even with the key and wiper switch off. To me, this was a sure sign of a broken motor (internal short or something). This was a bad assumption because I did not understand how the thing was actually supposed to work.

I called my dad who got the car in about 1974, and he actually could not remember if they EVER worked. But my mom (who was there when he got it) said she drove it in the rain in the 80s and the wipers definitely worked. Hmm.

Upon further examination of the diagrams provided, I guessed that if the mechanism was stuck in a position where the wipers were not "parked", it would be expected that the circuit would still draw some power because it is attempting to park those wipers. If it was just stuck (physically stuck or just dirty commutator/brush), then freeing it up should allow them to park and the little cam or whatever is inside there would break the circuit and all would be well.

Anyway, they work now. Thanks to all who helped me I just feel kinda dumb for not figuring this out myself.