dlg993

I was reluctant to start a new thread on this topic, but feared the older ones would no longer get much attention. I have factory shop manuals, and have reviewed several threads related to convertible top operation. They are very useful, in particular <https://rennlist.com/forums/993-forum/557546-cab-top-latch-motor.html>. My top unlocks, but the motors then stop and the top does not lower. The 19 mm bolt heads are tight (torque?).
I read that, if one holds the switch in the "close" position, the top controller resets itself (at least for the 996). When I do this, the top moves to the locked position, and clicking sounds come from both motors. This I presume to be failed gear teeth, which prevents the microswitches from being activated by the cam (how close to being correct am I?). Three questions: I am having difficulty removing the motors from the frame after removing the four Allen screws; is there a special locking lever position, or is the unlocked position good enough? Second, is there any way to reset the controlling computer, as in the one with the cold solder joints? Third, the 557546 thread referenced above cautions one to replace the cams in exactly the same position as when the gearbox is opened; if the gear is missing teeth, is the cam still in the correct position for reassembly?
Thanks for any assistance.

Duggie

Not sure if this will be of any help but behind the bolts is a type of keyway that locates inside a slot on the gearbox, if the bolts have come loose at anytime and the key way has slipped then the roof needs re-aligning, the sensors are on the outside of the gearbox so you can see when they are in contact with the stops (sensors are on one gearbox only). The actual sprocket inside the gearbox is half moon shape..what I mean by that is, if you have a typical sprocket and cut it in half that is what you have inside the gearbox...if that makes sense !!...so if the roof mechanism has slipped on the gearbox then its quite possible the drive worm has passed the drive teeth on the sprocket, which might explain the clicking from the motors but nothing happening.
If the roof doesn't move at all but the motors are running its also possible the cables have snapped.

BSL

I know it isn't the question you asked, but one easy solution is converting to manual operation. The console switch is still used for locking and unlocking the top, but then you just drop the top down/put it up by hand.

si2t3m

First thing.

When the locking/unlocking motors stop, do you hear the rear motors for that lower&raise the top spin?

If the rear motors are not spinning, there are 2 microswitches where the top meets the windshield frame. IIRC, both microswitches must be realeased so that the rear motors engage. Check that both microswitches are not making contact.

CalvinC4S

The clicking you hear is from the motor over running the limit on the frame sprocket or "cam". It needs to be re-timed. When you play with the micro switches and run the top, it's very easy to run it out of synch/off track.

Remove the arm to transmission, then the cover plate. It will all make sense then.

vincer77

Another issue could be the drive-cable jackets have lengthened and do not engage the rear electric motors.

si2t3m

Hi read your post again.

When you say: ''I read that, if one holds the switch in the "close" position, the top controller resets itself (at least for the 996). When I do this, the top moves to the locked position, and clicking sounds come from both motors.''

What microswitch are your refering to? The latch motor microswith, the ''top has reached the windshield'' microswitch or the microswith located on the passengers side on the top gear.
The clicking sound is coming from the front top motors for the latch or the rear motors for the top movement?

dlg993

Thanks to you all for replying.

The clicking, actually almost snapping, is coming from the top locking motor/gearboxes, both sides. I'll have to admit that I wonder why there are microswitches in the gearbox and also on the top frame and contacting the windshield frame. It would seem one set or the other would indicate when the top locking motors should stop. That written, some questions got confirm my understanding of your answers:

Marc-Andre', the microswitch to which I was referring is the one inside the locking motor gearbox fastened to the window frame by four Allen bolts. Both microswitches in the top frame, making contact with the windshield frame, seem to be working.

Thanks, Vince. When I inspected them last, all seemed well, but another check is certainly warrented.

Previously, I removed the upholstery covers hiding the wormgear/sprocket boxes , and couldn't understand the functions of the microswitches there. At the time, the top was working fine, and I was just trying to make a minor adjustment.

The motors behind the rear seat seem to stop when the top unlocks, which certainly explains the top not continuing to open. I'm reluctant to open the wormgear/sprocket cases unless necessary, given a Rennlist post I read regarding the difficulty of reassembly. But, I also wonder what is causing the motors to stop spinning (fuse in the front compartment fusebox is o.k. Are there others?)

CalvinC4S, is removing the locking arms the trick to removing the motor/gearboxes from the top frame? I can't remember how the arms were connected, but removing the arms would certainly make motor/gearbox removal easier.

Thanks, Duggie. I understand the concept of a "half sprocket." The bolts to which you refer are the ones near the rear speakers with the 19 mm heads, yes? I read a Rennlist post that one should not remove them when converting to manual operation, but are you suggesting removing them to confirm the keyway is correctly positioned, and, if so, what would be the correct position?

Brian, I have read about making the system manual, and have opened and closed the top several times manually. But, I'm mostly a hobbyist, and would first like to try making the system work. And also open the locking gearboxes to confirm the gears are not without some teeth. At least one problem is that I can't seem to decide on an order in which to make checks. And, the proper function & position of the microswitches on the frame near the right side wormgear/sprocket box escapes me.

All that written, thanks again for your suggestions, and I will post my results on this thread.

dlg993

Duggie, do you happen to have a photograph of the inside of the wormgear/sprocket case? I have photographs of the locking motor gearboxes. Thanks again for answering.

si2t3m

Take a look here:

https://rennlist.com/forums/showthre...eferrerid=2982

From what I understand, the microswitches, the ones in the front latch motors control gear movement of the latches from the opened to lock position.

The microswitches on the top frame trigger the latch motors when pressed. When the microswitches are opened signal goes to the rear motors.

The microswitches on the passengers side top gear limits the amount of movement of the top motors in the closed direction and in the open direction.

When I took my rear top gears apart, because I was using the top in manual mode and the rear motors where still activating the gear mechanism the 1/2 gear got out of sync to a point where the small gear in this mecanism was spinning free. Made some sense on how the mecanism was working. Good thing is to make a mark on the gear key where the 19mm bolt goes. This way you know where the gear is and your can adjust and sync them but plugging and unplugging the cables at the motor end.

Taking these apart, is easy. Reassembly is doable (i've done it) but an extra hand would of made the job easier.

Duggie

Sorry, i don't have any photos. I had problems with mine sometime ago and decided to strip it down, it really is quite a simple mechanism, you just need to take your time and get to understand the mechanics of it.

The bolts lm talking about are the ones behind each seat which connect the roof to the gearbox, you remove a round plastic cover to get to them. if you loosen the bolts this will disconnect the drive between the gearbox and roof, don't take the bolts completely out unless you intend removing the gearbox. If you do loosen these bolts and manually operate the roof, it isn't just a case of re-tightening them, you will need to make sure the key way and the slot in the gearbox are aligned, this will become clear when, or if you take this route.
The post from si2t3m makes a good point about marking parts before loosening or removing them.

dlg993

Thanks Marc-Andre' and Duggie. I think I have enough information now to start correcting the problems, especially with the photographs on the thread suggested by Marc-Andre. Indeed, Duggie, when manually operating the top, I did just re-tighten the bolts with no regard for the key-way and slot in the gearbox.

It will be a couple of weeks before I complete this work, but, again, will post my results on this thread.

Thank you all for your assistance.

dlg993

Finally go to checking stuff on 2 Oct. I took the 19 mm head bolts out and detached the frame arms from the box. Using the switch to lower and raise the top, I confirmed that the cables were intact and the worm-gear was still engaged with the "half-gear" inside the box. I then raised the top manually halfway, and, using the console switch, rotated the slots in the box shaft so they aligned with the frame arm key (welded to the frame arm), and bolted the arms into place. There was minor difficulty in keeping the copper and steel washer aligned, but finally the arms felt properly placed. So, in the end, the problem was that, in some previous moving of the top manually, the frame arm key and the gearbox slot became unregistered.

A problem developed in that there were actually four steel washers. The information on this forum indicated there were two, one per side. It turns out that the washers were varying thickness, and when I took them off, they appeared to be single washers => I didn't know how many of what thickness went where. I should have kept all the stuff from each side separate, but didn't. When reassembling, I put only one steel washer on each side, choosing the thickest two. Not certain what may happen as a result, and I may experiment with adding the other two. Now, the top raises and lowers using the switch.

Next problem is getting the locking motors out of the top frame. I have removed the four Allen bolts, but can't seem to find an orientation that allows the motor to be removed. Based on the sounds coming from the motors, I think there may be teeth missing from the gear inside.

More as it happens.

Cemoto

Admin,

Since cab tops seem to be/are problematic as are SAI issues, it might be helpful to have a sticky with all the cab top solutions readily available.

Anyone want to tackle that?

Regards,

.

dlg993

I have a Word file with many instructions and photographs taken from this site. It is about 34 pages long, as of tonight. Sadly, I didn't keep track of who was posting to give proper credit. Nonetheless, if someone can tell me how to post the file as a "sticky," I'd be happy to do so. Indeed, it is just a record of other folks experiences, and the very helpful documentation they provided.