Boot-lid stay

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Henrik

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I assembled the boot-lid stay on the car today and got really surpriced when I did a test of the mechanism. On a CSi with a steel boot-lid it opens gently and stops in a position about 15-20 cm above the opening. When I opened the aluminum boot-lid it was almost "launched"with great force to a fully open position. The force provided by the torsion springs are obviously to strong for the light weight boot-lid. This force also give the boot-lid a new and unwanted curvature in closed position.
The car was dismantled when I bought it so I have no experience with how it worked originally.
Was the CSLś delivered with this solution or did it come with a support, like for the bonnet?
I haven't installed the trim panels or tool tray (which I do not intend to install) yet, but I think the weight of these parts isn't enough to counteract the springs.
After a lot of thinking an idea might be to bend the ends of the torsion springs to an angle that makes a softer opening.
Any thoughts about this, anyone?
 

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i have just done my boot lid and yes - without the tool tray and liner your lid will fly up and could damage i had to lock my boot lid until i put the tray in just in case some fool opened it up.
With the tool tray in ( mine is only 1/2 full) the lid pops up about 150mm and then stops.
The only option you have if you dont want to put the tools in is to de torsion the bars.....
 
Hello
You can change the force of the mechanism with the part in the red circle. Moving it back or forward changes the force. I also lengthened the 2 holes in this part to get the correct force for my heavy lid with the spoiler mounted.
There is no force from the torsion springs when closing the lid. The lid is falling the last 20 cm because of its own weight
Ulrich

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Good to hear that I'm not alone with this problem:(.
I fear that the force needed to close the boot lid can lead to fatigue over time, in addition to this it will be a nightmare to correct the sits. I have just finished the bonnet and don't want to go trough an endless try and fail again.
Modifying the brackets on both sides seems to be a good idea instead of bending the torsion springs, which could be very unpredictable. Easy to experiment with a piece of metal to find the right force before the correct length between the fixing point and the torsion bar is settled. Also easy to reverse if more weight are added to the lid in the future.
Thanks guys!
 
Your problem is most likely that you have CS/CSi torsion springs in combination with an aluminum trunk lid. The CSLs equipped in this configuration had weaker bars (BMW ETK and observation). Since it may be difficult to find some original CSL spring bars, your best option may be to have those that you have tempered to a weaker load.
 
Gerrit said:
your best option may be to have those that you have tempered to a weaker load.
Click to expand...
That was my first thought, but it will be a challenge to get the right load. And you only get one chance as I see it.....
 
I need to take my car out this weekend. I’ll measure and post the lbs of force required to unlock the trunk out of fully open. That is with a steel lid and a mostly empty toolkit. I can load up the tray with factory tools and see the difference.

If anyone else has a fish scale please participate in the exercise. I can guarantee that @Drew Gregg has a scale. Could be a little out of calibration from measuring trophy catches. :D

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