audi49

Took care of another one of the 944's 'greatest hits' this past weekend. As you can see below, the plastic gears were toast... one side didn't raise at all, the other side still more or less worked.
Followed the Clarks Garage procedures.
Notes for anyone that plans on doing this:
-First... as directed definitely check the slip clutch torque on the motor. Mine was at 7+ Nm and probably contributed to the stripped plastic gears. I ended up setting mine at 5.5 Nm, at the low end of spec.
-Although the Clarks procedure calls for the removal of the weather stripping across the top edge of the hatch and accessing the lifting arms assemblies from the rear (I did that but access didn't look good), i ended up removing the trim on the back edge of the sunroof and pulled back the vinyl on the front side of the lifting arms and was able to access everything quite easily from the front.
-No need to put the sunroof back on to test the lifting arms... just press the switch between the sun visors. However, it is important that the arms extend far enough in 'locked' position so that their position can be 'tuned' within the sunroof guide by adjusting the limit switch position (so a trial fit before everything is put back together is a good idea).

Felt good to get this job finally done and having a functioning sunroof (that i can now lift and so that it don't get the traditional lifting of the sunroof at highway speeds.)!

pfarah7

Of all the issues my car has had, the sunroof assembly caused the most grief, at least so far... Well done on the repair!

tempest411

It looks like it'd be easy enough to make those out of metal on a mill. I wonder if anyone's tried it?

dmjames

I seem to recall the theory is that these gears being plastic means that when things go wrong with the microswitches (because they always do!), the gears strip rather than more involved stuff.

No Lag

Nice job. I just replaced mine also. Just about all the teeth were stripped!
I did find however the root of my issue was the micro switches by the motor were not engaging, so the motor kept turning and screwed the gears!

audi49

Good point. One thing i was not clear on is when you press the button to put the arms in 'release' mode, should the motor stop due to the limit switches or does the slip clutch on the motor simply do its job and the motor doesn't stop till you release the button. (Does my question make sense?). Reason i ask is that with my limit switches in an initial position that i adjusted them too, the motor kept going after the arms were released (but the slip clutch did its job). Then i fiddled with the limit switch pair to adjust the arms and all of a sudden the motor stops when the arms are in release mode - I assume that this is actually the right behavior?!

tempest411

Gears make for a horrible fuse in a mechanism. If it were a concern, and it sounds like it is, Porsche should've incorporated a slipper clutch into the system-though I'd hope that the increased current from the motor driving against a hard stop would blow the fuse first.

audi49

There is a slip clutch on the motor. Torque needs to be within spec however.

No Lag

My motor stops in the release mode so I'm guessing your switch is bad or not engaging. I had to loosen mine and adjust them to make sure they both engage. The bracket their mounted to can flex enough to stop engagement. I confirm the motor would stop before I put the gears in. The clutch is really your back up.

RacingDreamz

My roof goes down, but not all the way on the rear driver's side. Would this be gearing?

No Lag

Sure nuff. Did you replace gears recently? If you did you may be off a tooth or two compared to the other side. If you didn't replace the gears perhaps one side is stripped!

RacingDreamz

Thanks for the reply. I can push it down, almost all the way, but it won't stay down. Still gears? If so, where do I get the gears and how do I change them?

No Lag

I think you have no teeth allowing you to put it down. That said there are two sunroof types on the 944. I have the later model. Clark's Garage website is your friend. Lots of tutorials. As far as gears. There readily available. Do a search,eBay, etc. should be in the range of 8-9 bucks a piece on the low end.

RacingDreamz

Probably what it is. Thank you for all the help.

audi49

FCPeuro.com was the cheapest source i found (these are for a late model... not sure if they're the same for early models).

https://www.fcpeuro.com/products/por...68-94456443001

And as already noted, clarks garage online has some very good write-ups. Recommend a couple of cups of coffee (or a couple of beers), read through the material (twice), and go for it.