Anyone tried modifying or adding controls to the windshield wipers to allow for intermitant wipes? Are the controls for such in modern cars simple enough that they could be bolted on?

Bosch and Hella both make good quality, variable-delay interval wipe control kits. You get everything you need to add the function. I prefer the Bosch kit, but it's harder to get (has to be specially ordered from Germany). There're usually a few of the Hella kits around North America.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

It wouldn't be terribly difficult to build your own using a 555 timer chip, a pot, and a relay. I've been thinking of doing this myself and hooking it into the low speed circuit of the 2 speed wipers.

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

I had a parts-store intermittent wiper control on the single-speed wipers in my '64 Valiant. It worked well enough, but always gave two wipes per cycle.

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"When you find a big kettle of crazy, it's best not to stir it." - Pointy-haired Boss

1964 Valiant V200, 225/Pushbutton 904
BBD, CAI, HEI, LBP, AC, AM/FM/USB, EIEIO

If you've got wipers that don't reverse to park, it is trivial. If your wipers need to reverse to park, as many '70s B-bodies do, it is not.

The park switch in the latter does not open when the wipers are running forward, so any aftermarket kit I've seen won't work. All the kits I've seen are just a monostable and a relay or SCR and just turn the wiper on momentarially and let the park switch stop it.

Years ago I bought a J.C.Whitney kit that "fits all cars" - I found that was useless with my 1975 Dodge Coronet w/ 2sp wiper. Any delay needs to know where to stop the motor - I tried by time, but the wipers ended up in odd places, and I tried parking them after each wipe using a 4PDT relay, but the that was also very annonying.

I finally used a Hall effect sensor, 4PDT relay, and some electronics to make it work. All I could salvage from the JCW kit was the knob, which subsequently broke. The sensor was in the air plenum by the wiper arm and the box w/ relay and NE556 delays and sundry behind the dash, where it intercepted the wiring from the wiper switch.

It was hard to install, expensive (~$120 in parts in 1991), but worked very well for many years.
If I were going to do it again, I'd try to put the sensor inside the motor and send a modulated signal through the stock harness to the electronics.

Chrysler came out w/ delay wipers in the late 70s or early 80s by adding a switch inside the motor; I've not looked into retrofitting them to older models.

We added interval wipers to my son's '64 Dart GT using a Ford delay module and switch from an F150. Our Dart is single-speed wipers, and I had to make a little circuit to emulate the Ford motor "cam switch". Works slick, and looks completely original.

I would be happy to share details. Also, if someone can provide me a diagram of the internal workings of a two-speed or "reverse-to-park" Mopar motor, I would be glad to see what it would take to adapt the Ford setup.

The wiper switch fits nicely in the '64 dash. A little filing on the original hole and trim the switch shaft. The original knob fits too!

We got the switch and delay module at our local Pick-N-Pull. Switch was $8, module was $5. Additional emulator circuit is about $5 in parts.

Phil

rockndood: I for one would be very interested to see how you determined the stop location.

Unfortunately, I have never found diagrams of the innards of '70s 2sp & 3sp wipers, but all that I've opened up used spiral cut plastic gears, lots of heavy grease, and a park switch that was kind of a squashed C-shape that engaged a pin on the main gear only when the gear was running in reverse. It never opens in the forward direction, and breaks easily if the motor doesn't stop fast enough in reverse.

The only hard part is to get a reliable signal to tell you where to stop. There is little space in the gearbox to fit anything extra in. I tried getting a signal from the current draw of the motor (the torque should be least at the ends of the swing), but it didn't seem to work very well.

If you can figure a really good way to do it, I'm sure many of us would appreciate it. Thanks, K

Using the Ford module and the single-speed Mopar wiper motor (not a "reverse-to-park motor), I did not have to determine the stop location. Basically I fooled the Ford module a bit.

The Ford Module logic is as follows:

A. The "run" signal goes to 12V.

B. Once the motor turns a few degrees, a cam switch inside the motor connects a "sense" signal to the "park" signal.

C. When one sweep is nearly complete, the cam switch breaks the connection between the "sense" and "park" signals, which causes the "run" signal to go to 0V. In the Ford motor, this also connects the armature to ground to dynamically brake the motor.


The essense of the Ford module is that the "run" signal will remain at 12V until the "sense" and "park" signals have connected, then disconnected. Upon disconnect, the "run" signal goes to 0V.

The Dodge single-speed will auto-complete and park after each sweep. Thus I built a simple circuit to do the following:

1. The "run" signal rises to 12V, which starts the motor. It also begins charging an RC and relay circuit (call it Relay1).

2. When Relay1 engages, it energizes a second RC/relay (call it Relay2).

3. When Relay2 engages, it connects the "sense" signal to the "park" signal. It also disconnects the first RC/relay combo from 12V, and the Relay1 capacitor begins to discharge.

3. Once Relay1 releases, it disconnects RC/Relay2 from 12V.

4. Once Relay2 releases, it dosconnects "sense" from "park," which causes the "run" signal to go to 0V.

5. The wiper motor will auto-complete the sweep.

I simply timed the RC circuits for all this activity to transpire in just under one sweep. This means that the minimum interval is probably a tad shorter than it would be if I had sensed position, but close enough.

I had considered using a microswitch to sense cam or pivot position, but the RC/Relay was an effective solution for the single-speed application. I had also considered using a timer chip, but relays and caps are cheap and durable.

From the information about the reverse-to-park motors, my simple solution appears inadequate. In that case, sensing position is vital.

Thanks rockndood for the details; it sounds very reliable.

Some people use a NE556 for both time delay functions and a single relay or a SCR. Also, reverse biasing a diode across the motor helps suppress transients due to large |dI/dt| in the motor, prevents burning the relay points, and makes the motor stop faster.

I love capacitors as timers..............

Not many people can think analog anymore.

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Analog rocks



Though it's still run to my nice digital computer to listen to my 20 gigs of music, some of which I had to rip off of vinyl in the first place... Explain that paradox...

I devised a simpler adaptation for the single-speed Mopar wiper using the Ford control module.

This version uses one relay, one capactor, one resistor, one rectifier, and establishes "end of sweep" based on the motor's "park" switch instead of inferring by R/C timing.

If anyone would like a copy of the schematic, lemme know. Or if y'all want me to post the schematic, I can do that too.

We also now have a variable-speed Mopar motor with reverse-to-park, so I will be looking into adapting that for interval wiping.

Please post a schematic, photos, and a write-up. It might make a good article.

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"When you find a big kettle of crazy, it's best not to stir it." - Pointy-haired Boss

1964 Valiant V200, 225/Pushbutton 904
BBD, CAI, HEI, LBP, AC, AM/FM/USB, EIEIO

Yes, please post!

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

I will post the schematic and some photos in a couple weeks.

Thanks for the interest!