Originally Posted by drmrbrewer

Thanks for all the advice. I had a closer look today and took a couple apart. There are indeed a couple which have no resistance left in them, so I assume the wax has all gone. On another couple, the securing nut which holds the threaded part close to the black cylinder has seized up. I think I should be able to turn the black cylinder to adjust its position, but the thread is seized up. No amount of WD40 and brute force will shift it. There are some others that turn easily.

So it seems that some replacement is necessary. Are these standard parts... Will a replacemenet cylinder fit with my existing openers, or do I just buy a complete replacement? I may not be able to extract some of the cylinders from the holding nut/collar which as I said before has fused itself around the threaded part.

I also have several louvre openers that have seen better days, so that they are locked open.

Or perhaps I should just do it manually...

Mike