Porsche Enthusiasts Club Forum

This is a quick write up of an alternative replacement of the windshield wiper motor that I have found for the 944 (which should also work for the 924/968)

A little background.

As with many other 944s of similar age the windscreen wipers had decided to work only part time, until they packed up all together. This is a fairly common issue where over-time the moisture seeps into the casing and rust seizes up the motor. Furthermore, over time the plastic gears driving the wipers begin to wear out, although that's fairly rare. Such was the case with my 944. Of course the first steps I took was to check the fuses and relay for the wiper motor, which were all fine. Since the wipers are required as part of the MOT I've had to keep the car off the road until I could remedy the issue.
Initially I had followed the excellent video instructions on how to disassemble and clean out the motor (https://www.youtube.com/watch?v=eWpZI4KUrUk). However, when testing the rebuilt motor on the bench it had still barely managed to rotate the wiper arms. My further investigation of the motor actually led to a broken plastic mount for the resistors
So presented with the prospect of buying the replacement wiper motor for the princely sum of £620 from Porsche (or from specialists), I had decided to try out an alternative build.
There had actually been a similar fix done before (https://rennlist.com/forums/924-931-944 ... -part.html) but this required the butchering of the wiper arm mount which I wanted to avoid. Digging around with the various wiper motor specifications I had discovered that the Mk2 Scirocco's wiper motor shares the same mounting dimensions as the 944 so I used that as the basis for this mini project.


The fix.

Advance notice: the new motor supports only 3 wiper speeds, so this will lose the "berserker" speed.
The intermittent, steady and fast wiper speeds will remain exactly the same as before.

Required items

• Wiper motor: Meyle 1009550003 - £36 on eBay
  EDIT: Seeing how the Meyle motor is getting hard to find, the newer equivalent seems to be the Febi Bilstein model 17086 (Approximately £32 on Amazon)
  
• 5 Pin connector: 171971835A (5-AC074, including terminals) - £3.79 on eBay
  
• 3 Pozi pan head bolts: M6 x 16mm - £1.20 on eBay
  
• Soldering iron kit
  
• Wire cutters
  
• Small metal hacksaw
  
• Metal file
  

For the removal of the motor from the car please follow the excellent instruction in this YT video:
[youtube]youtube.com/watch?v=eWpZI4KUrUk[/youtube]

1. Cut the original wiper motor cable about an inch at the end nearest the motor.

2. Solder the terminal plugs to the cables. You do not need to use the black cable (used for the super fast speed setting), so you can simply fold it and insulate it.

3. Connect up the terminals in the order shown in the photo below and tidy up the cables with cable heatshrink.



4. Remember to connect up the ground wire to one of the case screws.

5. Because the new motor sits slightly lower on the VW, we have to slightly trim the mounting holes.
Thankfully since the mounts are made of aluminium and have a marking on where to directly cut them, its very straight forward.
In the below can see the mark where to cut the mounts using the metal hacksaw (as if VW knew we'll be doing that for the 944 )



Once the mounts have been cut, I'd recommend smoothing out the surface with a metal file for a better fit.



6. Using the new shorter 16mm M6 bolts attach the wiper motor onto the arm mount. You can use a bit of locktite for security.

7. Make sure to move the wiper arms to their furthest alignment position before connecting the spindle to the motor.
If the wiper arms are not set to their end points when you turn on the wipers they will go down first, and then up.
This can damage the motor and your wipers so take your time to check this. See the YT video as the chap explains alignment on there.

8. Connect the spline mount to the wiper motor. Please note that the number of spines may not match up.
This however shouldn't matter once everything is tightened down as they'll be held together very tightly. Again, a little bit of loctite is recommended here.

9. Re-fit the mount back on the car and bolt it down. Don't forget about the ground wire.
I'd also recommend using some dielectric grease on the exposed terminals to protect them from any rust in the future.



10. Before attaching the wiper arms and re-attaching the plastic cover I highly recommend you test out the motor.
Re-connect the plug and turn on the intermittent wiper setting.
At the start of each rotation check to see that the spindles are turning in one direction (counter-clockwise)
If at the very start the spindles are first turning clock-wise it means the wiper arms are not aligned to their max point and will need to be re-aligned.

11. I found that the small plastic cover directly above the wiper motor may be contacting the terminal connector very slightly.
For this I simply filed down a very small groove at the contact point in the plastic. It should fit back into it's place absolutely fine.



12. Once you have tested the wipers and everything works as expected, make sure to tighten everything down and re-assemble the rest of the heater and plastic covers.

A little shameless plug on my behalf, if you are missing the small plastic covers on the bolts holding down the wiper arms (part number 944.628.305.00) I had 3D modeled an exact replacement for those. You can see the end result HERE. If you do require a pair, just drop me a message and I can have these printed out and sent.

Conclusions.

Once I had tested the motor and everything seems to work as expected, I booked the 944 in for an MOT, and lo-and behold, passed first time around.
So I guess if you don't mind getting your hands a little dirty it's a pretty good way to save yourself over £500 in part costs.
Oh and the new motor saves some weight over the original, so for you track day aficionados that's got to be an extra few seconds off your lap times

So, hopefully you found this write up useful. If you do require further info or some help feel free to message me.

Happy driving!

Excellent write up, well done! I'm sure this will help many of us in the future. Thanks for posting.

Dear VSL_London

Great post. I have the same issue. Do you know if your fix works for post-1988 models?

Peter
N20 London
944 S2 1989

Hi Peter,

Looking at the part number for the wiper motor (94462830301) it looks like all later versions of the 944 used it, so I suspect it should be a direct fit for even the later S2 models (though I tested this on my '89 2.7L only). I sincerely doubt the casing over the motor would have been changed in the later models, so Im pretty certain it should work fine.

Thanks!
Victor

great write up, well done

Hi Victor

I didn't find the motor you recommended (Meyle 1009550003)
So went searching and if you put Porsche 944 S2 1989 into GSF Car Parts you get this:
https://www.gsfcarparts.com/940gm0010
Turns out to be Chinese .. Wai WPM9000 ... https://www.waiglobal.com/uk_en/wai-wpm9000.html
So I paid £59.52 advertised by GSF as including a 45% discount but almost certainly a lower standard product than the one you recommended at £36
Elsewhere it is being sold as suitable for a Vauxhall Corsa (not even a VW)

But all that said it has the right size / spaced 3x M6 bolt fixings and coned/splined drive and in other ways looks similar .. 5 contacts

It sits at a different angle but that does not seem to be a problem
It is quite a lot smaller than the original but the gearbox is deeper and as per your post needs 5-6mm cut off the cast alloy mounts and a connecting block adaptation to plug in.
It works but is not a perfect fit so I suspect there are better alternatives out there.

On the new motor I cannot find any definition of which colour wire does what so probably have to work it out by trial and error?

On the car original colours are:
Motor (male) .. Engine bay* (female) .. function
Yellow .............. 1 Brown/White ............ Intermittent
Green ............... 2 Black/White .............. Low speed
Black ................ 3 Green ....................... High speed
Blue ................. 4 Black/Yellow x2 ........ Live (to Fuse #24)
Red .................. 5 Black/Green .............. Mid speed
Brown .............. 6 Brown ........................ Earth

* Engine side colours and numbers are also as per the PET wiring diagram

Chinese motor comes with no handbook or info on website.
5 wires: Red, Yellow, Green, White, Black.
Black is obviously Earth as it has a connection to the housing.

Any suggestions welcome!

Peter

OEM motor (male) Engine bay* (female) . function ................ Wai motor
Yellow .............. 1 Brown/White ............ Intermittent ........... White
Green ............... 2 Black/White .............. Low speed ............. Green
Black ................ 3 Green ....................... High speed ............ Yellow
Blue ................. 4 Black/Yellow x2 ........ Live (to Fuse #24) .. Red
Red .................. 5 Black/Green .............. Mid speed ............. also connect to yellow
Brown .............. 6 Brown ........................ Earth ..................... Black