Alex wrote:
If the existing spring tension is too much i.e. the door fly's up
then you would release tension by allowing the spring to unwind by
one turn this should be down,the reverse for not enough tension i.e.
the door drops by say 150mm.

The trouble is I'm not 100% sure that the mechanism was installed
the right way round, hence up / down may be reversed. The colour coding
on the spare parts from Henderson appears to be the opposite of that on
the parts I removed. I'm assuming that when the instructions refer to
left and right they mean when standing inside the garage looking towards
the door.

I would advise caution and the wearing of protective eyewear also
ensure that you have the correct size bars to prevent slippage and
maintain a good grip on these bars at all times.

Absolutely. I've got the proper bars from Henderson, and have a healthy
respect for the spring.

Thanks

Chris

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