I have a 2006 AMD 601 B XL with weakening springs which have dropped the canopy on me several times recently. I was happy with the 40 lb originals and am wondering if I should replace with one 40 lb and one 60 lb . Can anyone confirm that two 60 lb springs are not too much lift?


Ted Haller 620TH

300 hrs 25 since wing mod.

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Hi Theodore

I have the 650 canopy on my XL which I think is lighter than the long XL canopy. They sent me another set of gas struts with my kit which were identical to the first set. Neither pair will hold the canopy unless it is nearly all the way up. I am going to get someone to regas my struts. I think that airmail may have something to do with the pressure drop in the struts, I could be wrong. McMaster Carr have the identical struts in various pressures. Unfortunately I live in Australia and they wont ship international and fear if they did, airmail would once again wreck them, I could be wrong. My understanding is that the guys who can regas struts can add pressure to any strut with a vacuum or pressure chamber however it works. I am not sure weather it is just that we are supplied crap struts or if the world of Zodiac owners are just unlucky. The other possibility is that the struts are just not heavy duty enough to be upto the job. If you watch the AMD video with George Degonia, probably spelt his name wrong, he demonstrates the 650 canopy. He gives it a slight push and rockets up and cushes itself at the top before the end of travel. They definately don't seem to be the originals. What say you?




Ted, I have just replaced my 40 lb struts with the 60 lb ones. They open a little quicker if you just push the canopy up. In the breeze they hold much better than the 40 lb ones. It is still easy to close. So far, the canopy has not dropped on my head. Only a stronger wind will tell. I understand there are 80 lb struts available if necessary. I have a 601 XL-B.  Alan

Hey Alan,

Do you or does someone have the SUSPA part number for the 60 lb strut? I just acquired a 601HD project and would lkie to start out with something I don't have to worry about.

Thank you.


Note that gas springs should be mounted with the rod down, to keep oil on the seal. Otherwise they start to leak after some time and loose pressure.
Thanks for the feedback. My AMD 601XL had SUSPA C16-14864 40LB struts.  They were marginal in wind from the start and have recently gotten worse. Based on  Alan's comments I am ordering McMaster 9416k12 60 pounders.
put in the 60 lb McMaster Carr struts and they are great - solid in the up position but easy to pull down for closure

Hi Theodore

That's great news. Just a couple of questions though.

Did McMaster Carr send the struts by road or air freight?

When you unlock and push your canopy up does it fly up and cush itself on the gas before the end of travel?



The struts came UPS ground and arrived 24 hrs. after the order! When I raise the canopy I keep my hand on it to slow it down at the end of travel. If I didn't do that it would bottom out pretty hard against the struts.

I'm new to the Zenith list, but I have a Dragonfly which has the struts. There were many different variations tried over the years. The biggest problem was the struts were mounted with the shaft pointing up ( as mentioned previous). This lets the gas leak out quickly. The strut will last 10 times longer with the shaft down. Every pic I've seen of the 601 struts have them correct, so this does not seem to be a problem.

One trick that was used was to file a notch in the shaft at the full compression point to release some gas if the struts are to strong. Then be sure NOT to compress to this point when installed. There were others that soldered Schrater tire valves to the cylinders. Then you can add CO2 from a cartridge. I'm not endorsing the later, just thought I'd pass along some option that have been used.

Good luck,

Bob M




Here are the CO2 tire inflaters used to add gas to weak struts with Schrader valves.

Bottom of the page.


Bob MO


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