986 disaster!

[ttaunton]

Lovely day for a drive with the top down last month....Bang! The top (RHS) tied itself in bent knots. Anyway, straightened the bent bits, replaced the broken bits, L and R side gears cracked so replaced, and a month later it all "sort of" works. LHS Bowden cable had snapped, probably the initial problem. However; Left and Right Gearboxes are both sitting perfectly on their reference marks, but the clamshell levers are at different angles, about 2.5 inches difference in height measured to the bodywork, also obviously the slider track position is then different L/R. Surely with the gearboxes on reference position, the design would mean that L/R clamshells should sit level throughout the full range of moment, roof up to roof down? I can obviously rotate a Bowden cable to match the angles of the clamshell levers, but having tried that, it seems that the angle of the L/R clamshell levers won't then match throught their full range of movement. Any help appreciated, needless to say!

[mikefocke]

See if anything in here helps. I know nothing, just hosted but Maurice/1StChoir worked on lots of them in the NE. Doesn't anymore.

https://sites.google.com/site/mikefocke2/thetop-itsmaintaincereplacement

[ttaunton]

Item number 3 in your link sounds it might be some help, but the essential picture that accompanied it is no longer there. Mine is a 986, but I don't recognise the linkage you mention, attached to the "....slotted screw onto which the body-colored support arm of the clamshell is attached etc...." Maybe a later model of Boxster? One thing that I would be very interested to know is the part that the microswitch plays that is mounted in the LHS gearbox. There isn't one in the RHS gearbox. My car's clamshell behaviour is excellent with respect to the hood going up; the clamshell ends up level, and everything is nice and taut. Roof going down though is the problem, LHS is OK, but RHS is poor, no tension there and the clamshell ends up a couple of inches up compared to the other side. All very obvious when the clamshell is removed and there is just the L and R arms being driven.

[tcora]

One thing worth checking is whether or not your clamshell is bent from the original incident. If you take it off the car and lay it flat on your garage floor, you should be able to c9nfirm that. If it is bent, well, bend it back (within limits).

It would also be worth running thru the steps in the video below to confirm that everything is correctly aligned internal to the transmissions.

https://youtu.be/Qre4S5QWeZg?si=c9XIkZQLmKDhptB3

These may both be things you’ve considered, but figured at least worth teeing up.

Regards,

[ttaunton]

Carried out a test today; Removed the clamshell, and instead bolted a length of 2"x 1" wood to the clamshell arms. I took two pictures, the first one is with the hood almost up, close to the latch at the top of the windscreen. The piece of wood is level and everything is fine. The second picture is taken as the hood is coming down, almost at its limit; you can see the slope on the piece of wood, and the RHS is up in the air. The LHS is fine. If I try and correct the error on the RHS, by undoing the RHS Bowden cable and turning the cable to try and correct the error, then the white ball joint on the RHS will pop off as the hood gets to its limit. Where do I go from here?

[tcora]

That’s a pretty cool diagnostic tool!

As you ran the mechanism from one extreme to the other, how did the movement of left vs right differ? Did right simply move more slowly than left, or did it move at the same rate, but not during the entire cycle?

[ttaunton]

Thanks for replying! Starting with the hood fully up, start to drop the hood. For some time the piece of wood remains level, indicating equal L and R. As the process continues...a slight tilt on the piece of wood which gets much worse as the hood drops.(second picture) Then the LHS reaches its limit correctly, leaving the RHS about 2" in the air. Basically the L and R don't track together. Horizontal track slider was correctly at the end on LHS and about 8cm or more short on the RHS. So I then backed the system up a bit so the LHS was not quite on its end stop, took out the RH Bowden cable and rotated it (long way!) until the sliders were exactly matched L and R. Piece of wood also went level. Put Bowden cable back in and then motored the roof over it's full range; from fully up to fully down, several times. Perfect! Piece of wood level over full range. I would imagine that the RH Gearbox reference mark, if I took it all apart and had a look would be a long way out compared to LH. Both sides, without the camshell fitted, now bottom out perfectly at their limit, hard against the stops. With the Clamshell back on though, the hood doesn't compress down fully on the RHS, by about 1/4", but can be flexed down by hand. Could be lack of torque due to Bowden cable twisting, not compressing the hood enough, or hood not folding fully and a bit scrunched up on this side. Difficult to tell!

[CarGuyNeil]

Thanks for sharing as it could help another one of us in the future.

Sent from my SM-S938U using Tapatalk

[tcora]

Winning!