BigMikeATL

I can give you some advise from experience.

I'm 6', 220lbs. so I can't squeeze between under the dash too well. I removed the driver's seat and it was still a PITA to get to. The absolute easiest way to access the cab top control unit is to remove the lower part of the dash. I think the time to remove it is a wash with the time it will take you to work under there in such a confined space.

First you have to remove the VDO control unit (2 nuts) that straddles the cab top controller. Once that is removed, there are 2 nuts that hold the cab top controller in place. Once I had a good understanding of how the units were placed under the dash, I was able to blindly reconnect and install the two controllers by feel reaching under the dash in a normal sitting position.

I removed mine to perform the mod to allow the top to be raised and lowered with the car running. If you need to replace the unit, find one from a 993 because that functionality is built into the unit as long as the hand brake is applied.

Good luck!

hawk911

one reason for the top piece to break is if the bolts holding the transmission in place are loose. This causes flex in the entire mechanism and it could bind up a bit. The rule of thumb is to always operate the top when on level ground too, not with the body flexed because of uneven surfaces.

Stephen70

I did exactly the same procedure last summer, I didnīt remove driverīs seat, Iīm approx 6ī and oh boy my back was ruined after the job.

I will document the installation procedure some way (at least with photos), to make a video is also an option... and actually an excellent idea. Iīm still restoring the cab top frame and waiting for some parts (left main bow) to arrive.

jimq

I need to pull mine out and fix some cold solder joints

Stephen70

Yesterday evening I reached a very important milestone in my project - the electric folding top mechanism works again!



Iīm still waiting my new left main top bow to arrive, should be here next week. After changing it, I will describe the top adjustment process with photos.

And - after that - itīs fabric time!

Major adjustment points are the bearing brackets below the transmissions, two 17 mm nuts in threaded fork tightened against each other, and a butterfly-shaped part between them. The buttefly part can also be moved horizontally.

Stephen70

It took longer than expected to get new main top bow here. It finally arrived last week, now installed.

Pictures:

https://skydrive.live.com/#cid=E97DD...867720FF%21105

It was very easy to install now when there is no fabric. I used some 5 mm Allen bolts as a substitute for original riveting.

I started to adjust my top for perfect opening and closing procedure, as the mechanism and electricity is OK now (or thatīs what I thought...) Anyway, I hit a snag here. I think I have some issues with my cab control module.

The problem is that the latch motors are out of sync all the time. Left one works perfectly, but the right one turns open more than it should, causing some problems when opening the top. It seems that it doesnīt mind the internal microswitch at all - just turns over. I tested the microswitches of both latching motors by turning them by screwdriver, both switches are OK and the circuits open and close exactly at the same positions on both sides. Then I changed the latch motor connectors for testing so that the left connector feeds the right motor and vice versa. Now the left one opens too much. So, the motors are OK and the control module is not OK as the faulty operation comes from the right connector.

I think I replace the control box with new one from 993. I have already re-soldered some bad connections of my module, still not working right. Damn!

Harry Apps

Do a continuity check of the harness first, it is possible that you have a broken cable caused by the bending during operation. If you do change the module, you will need to modify the wiring - there is a TSB for this.

Stephen70

Long time no see - just due to extended delivery times of new control module... and some work-related things.

I checked all the wiring, everything seemed to be OK - except that some previous semi-professional mechanic (not me ) had connected the right latch motor to the connector of the left motor and vice versa. I donīfind any good reasons for this, anyway it messed the procedure to adjust the top bar microswitches as the microswitch and latch motor work as a pair. Sorted now.

...Yes, I made some latch motor tests by changing the connectors by myself as well, but they seemed to be connected the wrong way originally. So - my test set-up was actually a right way to connect them. The wire colors revealed the wrong connection.

I have installed a new control module from 993 - and added this extra wire from handbrake switch to the module to make the top work only when handbrake is on - like in 993. Works very well, latch motor sync issues are gone and now my top works also when engine runs.

I have also adjusted my top mechanism to work very well without the fabric, anyway a minor final adjustment will most likely be needed when the fabric is back. We will see.

So - now (finally) itīs time to start installing the fabric.

Jacke2c

Looking forward to seeing pics when done!

Stephen70

The top has been installed. Itīs not completely ready yet, put the fabric is on. Iīm quite satisfied, itīs very tight and fits almost like a glove. I will write a thorough explanation of installation procedure very soon. Some installation pictures are already available at my Skydrive photo booth:

https://skydrive.live.com/?cid=E97DD...867720FF%21105

Please check them out. If someone cannot enter my public Skydrive photo booth, please let me know.

Gus

In looking at your picture I notice that the snapp fittings around the base of the top are installed in the single layer fabric rather than the double layer which is just a little lower. I had the same issue when I installed my top. I found that the edge of the top now is right at the bottom of the tonneau cover and is visible. Something I am not happy with as I didn't have the top showing before. It appears to be a matter of raising the edge of the top all around about a 1/2 inch or a little less. This is really noticeable on the side were the two sections join and there is a little flying flap were if the snap fitting is, as it is a little high. If the fabric was raised you would not have the flying flap. I am thinking of going back in and try to raise the fabric. But, I am not sure that it can be done due to the location of the interior fabric that is used to anchor the top to the body. Did you look at the area when you installed the top???

Stephen70

I had this in mind during installation - but there really isnīt so much to do about it. I just measured the width of the flap below the lowest sewing line at the side - and there is a slight difference between the original top and my "Eurotop" aftermarket top. My new top has a bit wider flap than original. And - my top has already been installed as high as possible. I used those old Tenax fitting holes of the sheetmetal clamp where the lower edge of rear window section has been attached. It is impossible to install the Tenax fittings to the double-fabric area as there is no clamp behind it but the car body. And - it is also impossible to raise the fabric (at least in my case) as the fabric has already been glued to the clamp as high as possible.

So, a narrow flap of fabric below the edge of the tonneau cover will be visible when cover attached - but I think thatīs the price I have to pay for using an aftermarket top.

Gus

I think that was the same problem that was the same problem that I faced . trying hard to remember just what I was thinking at the time as it has been a while - but I think I finely decided to just have the next tonneau cover made a little longer - so the edge of the top would not show.
I think it is the way that the replacement tops are made. The interior fabric that goes on the inside is finished a little higher than the stock top - making the overhanging edge of fabric longer -
We live with it -

hawk911

I'm really interested in how you align the top, if you have to make adjustments.

Stephen70

Hi again,

First, Iīm sorry for not updating this thread for some time. Life has just been very busy recently. My top is completely ready, my 964 has also had some time on the road. Iīm very happy with my top, it is quite tight, no water leaks etc. There is some issues with rear window but letīs get back to these a bit later.

Hereīs quite fresh picture of my car. May look like SUV but thatīs the way I like it!