924Board.org

[wwdwgs]

.. to avoid glass delamination.
Using some help from youtube videos, I re-worked gas struts for rear hatch and this is how it looks like -[link to video
https://rumble.com/v6lcndg-porsche-924-944-no-more-rear-hatch-glass-delamination.-alternative-gas-stru.html
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924S

[Raize]

Cool. Are these the same gas struts or a different model of struts?
Guess the rear demist also stops working from this mod?

[wwdwgs]

The new gas struts are shorter and weaker.
The original-length struts (from Jeep) could be used, but... see my notes below. The idea wasn't mine - I saw a video, where a guy (an engineer btw), "unhinged" the stock-length gas shock from the body/roof area and attached it to the cargo hooks. The drawback is that the hatch opening height was about 16 or so inches. That was very inconvenient to load and unload anything. I wanted to increase the opening height. And, you can not use stock struts in this configuration, because they will push so much, that you may shatter the glass, trying to close the hatch. Those from Jeep may work. Video of original-length struts and how much the hatch is opened :

https://rumble.com/v51kaeq-944-porsche-hatch-gas-strutsshocks-alternative-mounting.html

The shocks are attached to the existing points on the hatch itself.
The obstacle was in figuring out the compressed length (similar to stock with stock shocks) and extended. If I wanted to increase the opening length, the shocks must have long travel, which is not possible with allowable compressed length.
Because of these dimensional restrictions, it's impossible to use stock-length struts.
Because of different mounting points, the "new" struts must have less than 65 lbs force (stock struts have about 60-70 lbs depending on the side - left side may carry more load because of rear wiper assembly).

So, I "weighted" the hatch at mounting points on the glass/frame side and started to play with the aftermarket struts.
I put weaker struts directionaly opposing each other, adjusted the total compressed length (very important).
The strut assy you saw on my video are rated 30 and 40 lbs. It's better to have both "upper and lower" struts with the same ratings - 40 lbs. With this ratings, the hatch must be pulled up until the struts kick in and push the hatch open.
If the hatch is equipped with the wiper assy, then the LEFT side must be "upgraded" to 45 or so lbs.
I didn't want to play with struts higher than 40 lbs, just because I didn't want to increase stress on the hatch upon closing it.
The struts are held to each other by metal "jacket", which wraps around them and prevents any movement.
Since these new struts assemblies don't conduct electricity for the light and defroster, I'll run wiring and new switches.
The reed switches, that I saw on one video, don't work well - they overload and "burn" after repeated use.
The main problem of possible glass-frame delamination is, therefore, avoided.
The hatch opening height is similar to stock's one.

The compressed length is about 16 1/2" - 17" (center to center) - I just don't remember after all these experiments. It could be measured when the hatch is closed. Extended - about 31 1/2".

The drawbacks of this "alternative" set-ups are:
1 - a need to run wires and switch for the dome light
2 - a need to run wires for the defroster
3 - more weight
4 - unknown longevity
5 - more labor
6 - more cost
7 - less favorite drinks left in your fridge

The benefits:
the glass/frame separation is stopped, or, at the least, lessened.
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924S

[wwdwgs]

Finally, the cargo area light works and defrost works after I installed other shocks.
Here is a little video: https://rumble.com/v6tp3lj-porsche-924-944-cargo-light-fix-with-new-gas-struts..html
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924S

[Goldwolf]

Where is that lower mount point? Did you have to drill out anything?
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1981 Weissach Edition #179