Grumpy owd man wrote:
Henderson mechanisms are the junk end of the market,



Yep, junk end of the market. My junk end of the market door gear
[canopy] has barely lasted 22 years and has had to have the 'cones and
wires' replaced, now let me see...oh yeah, thats it, once!

I for one cannot fault it!!

Thanks for all the tips guys. My door is 27 years old. Having thoroughly
cleaned and lubricated where necessary and replaced the cones & wires it
seems as good as new. As suggested by another contributor the spring did not
need retensioing once it had been lubricated. Heres hoping for another 27
years use.

Neil