Boxster Wiper Motor Options

[ConeDodger]

The 240Z guys use mid-90's Honda motors and IIRC, they are almost plug-and-play. Something about the electrical connections has to be adapted... They were the same era, maybe the same supplier?

[McMark]

Differences:

- The wiper linkage arm on the Boxster is longer (the gold piece below, pic from boxster). This means the 914 pieces may move faster then the Boxster. But that's a good thing. I can slow down a motor, but I can't speed it up.
(IMG:http://www.914world.com/bbs2/uploads_offsite/i18.ebayimg.com-419-1342975321.1.JPG)

- The bolts and drive shaft on the 914 motor are longer to allow the motor to clear the bracket in two place.


First the 914 bracket will bump into the Boxster motor. This can be clearanced easily with a grinder.


The second is the linkage drive arm will bump into the rubber mount. There is a little bit the can be removed from the arm and a little bit that can be removed from the rubber mount. This should clear. Worse case scenario, I can cut and weld the drive arm to have it run higher up. I don't want to do this because that will also make some undesirable forces that could lead to unexpected failure later on in life.


- Wiring
The red wire is the fast speed and the green wire is the slow speed (motor body is ground). The three unwired connections are the motor park connections. They look like simple pass through connections (which is what I thought they were), but I took off the cover and discovered connections inside that correspond with the connections outside. The center pin (#2) is the common rail. The inside pin (#3) is disconnected at the park location, but connected the rest of the rotation. The outside pin (#1) is connected at park and disconnected the rest of the rotation.

[McMark]

Here's a couple shots with the cover off. I noticed an important piece of info I missed the first time. Connection #1 is also grounded to the motor body full time. The implication is that those 'park' connections shouldn't be run as 12v switched. The need to be a ground connection off of a relay. Which makes sense.

One note that may not be obvious because of the grease. The metallic portion set into the white plastic is one solid piece of metal.

[Mike Bellis]

Great photos! I can really see all the dirt and grime.

Great write up! Keep going.

[McMark]

Stock 914 wiper motor looks exactly the same on the inside. That means it'll get wired up just like original. This'll be pretty easy.

[IronHillRestorations]

If you can do the motor swap, and figure out how to incorporate that intermittent wiper relay, this could the ultimate 914 wiper upgrade. Great work Mark!!

[McMark]

Here's an image from Kansas_914's build showing the wiring.
(IMG:http://www.914world.com/bbs2/uploads/post-373-1310215620.jpg)

To translate:

Boxster Motor ----> 914 wiring
red ----> black/purple
green ----> black/blue
1 ----> empty/no wire
2 ----> green/white
3 ----> red/black

(IMG:http://www.914world.com/bbs2/uploads/post-419-1342976166.jpg)

This wiring isn't confirmed - just based on research. Use at your own risk. (IMG:style_emoticons/default/shades.gif)

[smj]

- The bolts and drive shaft on the 914 motor are longer to allow the motor to clear the bracket in two place.

First the 914 bracket will bump into the Boxster motor. This can be clearanced easily with a grinder.

The second is the linkage drive arm will bump into the rubber mount. There is a little bit the can be removed from the arm and a little bit that can be removed from the rubber mount. This should clear. Worse case scenario, I can cut and weld the drive arm to have it run higher up. I don't want to do this because that will also make some undesirable forces that could lead to unexpected failure later on in life.

Probably a stupid question, but you've got to go with your strengths in life: Why can't you use spacers and longer bolts for mounting, and a widget to extend the drive shaft?

[McMark]

More work, no benefit. It would work. But in particular, the drive shaft widget would need a special cone shape on the top and the bottom to seat right. Lots of machining time to get that right. I would work, and it would be more elegant. But for a piece that hides up in a hole you'll never see, it'd be wasted effort. (IMG:style_emoticons/default/wink.gif)

[smj]

Fair enough. And thanks for sharing! This looks pretty cool...

[sixnotfour]

How about a 911 motor 3spds

[shuie]

Intermittent wipers would be cool. Is it any lighter?

[McMark]

Much lighter. Funny, I almost weighed them. (IMG:style_emoticons/default/wink.gif) Tomorrow.

Intermittent wipers is easy with a relay. It'll definitely be part of my installation.

[76-914]

Great info (IMG:style_emoticons/default/thumb3d.gif) After your finished you should move this over to the classy's.

[Cupomeat]

For those looking for intermitancy on thier wipers, a parallel thread provides all the answers;

http://www.914world.com/bbs2/index.php?showtopic=190927

(IMG:style_emoticons/default/beerchug.gif)

[Joe Owensby]

How did this turn out? Anyone else use another type of motor for the wipers?

[ClayPerrine]

FYI... a 964/993 wiper motor assembly is almost a bolt in on a 914. Gives you 3 speeds.

I did this already, and moved the motor to the left side under the defrost duct work.





If you use the 964 wiper motor as it is designed, the motor is on the left, and it will fit in the car if you alter the bottom mounting bracket. I flipped the wiper arm rack to make more clearance vertically for the AC, so I had to redo the mounting location for the motor.

It works great, I had it out in the rain last weekend.


There is one for sale on evilbay 964 Wiper assembly.

[McMark]

Well, 3.5 years after mocking this up, I actually did the install. My original assessment was right on. I notched the mount just slightly to make clearance for the motor body and removed the rubber mounting nut. I'll weld a new nut on the other side (that'll make it even harder to install). Now everything bolts up fine and the motor moves the assembly, just like it should.

I'm gonna go install it in a car now and see how it looks in real operation.

Note to self: take before and after videos. (IMG:style_emoticons/default/rolleyes.gif)

[McMark]

Well, that was an easy install. No surprises at all. My wiring in post #27 (above) is correct. Boxster motor is a little faster, which is more noticeable on the fast speed. And that's good because the 'fast' speed on a stock setup always seemed a bit slow.


https://www.youtube.com/watch?v=9uNOGzp9HrM


The bottom line, in my opinion, this isn't so much an upgrade. It's more just a replacement part that's in better condition than the old original parts. Also worth noting, the video/test uses two different wiper linkages. The linkage can introduce a lot of drag if there's corrosion or old gummy grease inside. The next step here is to overhaul the linkage for a complete wiper refresh.

[76-914]

Smooth as butter. Great job Mark.